Polar Bears Hunt With Weapons | Ice Gets Bent Out of Shape

MAGAZINE OF THE SOCIETY FOR SCIENCE s AUGUST 28, 2021

What Is a ? Fifteen years after lost its title, scientists still don’t agree

cover_pluto.indd 1 8/11/21 1:42 PM ON FIRE AND UNDER WATER SOLUTIONS FOR OUR BURNING PLANET AND ITS RISING OCEANS

“The world is on fi re, and no one “This wonderful book reminds sees that—or writes about it—better us of what we are capable of as than Stephen Pyne. This is a brilliant individuals to improve the future of guidebook to that future.” The essential guide to California’s long our planet and people.” —David Wallace-Wells, author of relationship with fi re, updated for the —Kirkus Reviews The Uninhabitable climate-change generation.

A history of our relationship—and “The book is carefully and clearly responsibilities—to our beaches written, demonstrating the author’s and their ecosystems. commitment to climate work . . . as well “Manages to inspire both pragmatism as the depth of her own knowledge and optimism, which likely stems as an environmentalist. Highly from the immense number of people recommended.” working . . . to better understand —CHOICE these issues.” —Forbes www.ucpress.edu

_C2.indd 2 7/29/21 3:59 PM VOL. 200 | NO. 4

Features

20 Pluto’s Place COVER STORY Fifteen years after astronomers voted to redefine “planet,” some scientists say it’s time to revisit that definition. A look back shows the term’s meaning has been ever-changing. By Lisa Grossman

24 The Debate Over Gender-Affirming Health Care As some states seek to limit transgender youths’ access to gender-affirming health care, researchers are studying the mental health effects of age- 24 appropriate care. By Maria Temming

News 6 Microscopic fossils push 10 The dino-killing 18 News in Brief back the start of animal unleashed a tsunami An odd gamma-ray burst life, a scientist contends that may have left may have been the death giant ripple marks under knell of a massive 7 The ’s Louisiana lasted for just a blip in The coronavirus razes geologic time, a study hints 12 Viruses help moth a crucial cell barrier to 4 8 Sea level change can cause caterpillars combat cause severe COVID-19 killer parasites a sea change in Santorini’s Black holes born with volcanic activity 14 How speedy squirrels magnetic “hair” quickly Departments Colliding light might jump from tree to tree shed it, computer 2 EDITOR’S NOTE without falling simulations suggest demonstrate Einstein’s 4 NOTEBOOK equation E=mc2 16 For some polar bears, To survive harsh winters, Ice can bend without 9 Pterosaurs may have stone and ice may be the pikas slow down their breaking; a baby taken to the air soon after perfect tools for hunting metabolism and snack on could be making hatching walruses yak poop 30 REVIEWS & PREVIEWS A new book tackles pseudoscience; another looks at the Big Bang theory’s origins

34 FEEDBACK

36 SCIENCE VISUALIZED See how a glass sponge alters the flow of water

COVER Pluto rises above the horizon of its largest moon, , in this illustration. Mark Garlick/ Science Photo Library/Getty 12 Images Plus FROM TOP: DREW ANGERER/GETTY IMAGES; ALMA/ESO, NAOJ AND NRAO, M. BENISTY ET AL ; AND NRAO, NAOJ ALMA/ESO, IMAGES; DREW ANGERER/GETTY TOP: FROM 3.0 US) BY-NC (CC BUGWOOD.ORG OF FLORIDA, JOHN CAPINERA/UNIV.

www.sciencenews.org | August 28, 2021 1

toc.indd 1 8/11/21 2:03 PM EDITOR’S NOTE

publisher Maya Ajmera Debate over Pluto’s planet editor in chief Nancy Shute editorial editor, special projects Elizabeth Quill status still carries on news director Macon Morehouse digital director Kate Travis features editor Cori Vanchieri Fifteen years ago, Pluto was kicked out of the planet club. managing editor, magazine Erin Wayman deputy news editor Emily DeMarco On August 24, 2006, members of the International associate news editor Ashley Yeager associate editor Cassie Martin Astronomical Union voted in favor of a new definition of associate digital editor Helen Thompson audience engagement editor Mike Denison what constitutes a planet. What was once considered the Lisa Grossman ’s ninth planet no longer qualified. behavioral sciences Bruce Bower biomedical Aimee Cunningham The public outcry was immediate. “In changing the definition of planet, the earth and climate Carolyn Gramling life sciences Susan Milius International Astronomical Union is messing with something much bigger than molecular biology, senior writer Tina Hesman Saey neuroscience, senior writer Laura Sanders it is,” one Science News reader complained in a letter to the editor. “Think of all physics, senior writer Emily Conover social sciences Sujata Gupta the dictionaries, encyclopedias, textbooks and websites that will need revision.” staff writers Erin Garcia de Jesús, Jonathan Lambert editorial assistant Aina Abell Many planetary scientists were upset too, though mostly for other reasons. As science writer interns Jaime Chambers, Nikk Ogasa contributing correspondents astronomy writer Lisa Grossman explains in this issue (Page 20), some research- Laura Beil, Tom Siegfried, Alexandra Witze ers thought the new definition — that a planet is a spherical body that the design chief design officer Stephen Egts (which Pluto is) and has cleared other objects out of its (which Pluto design director Erin Otwell art director Tracee Tibbitts hasn’t) — was too restrictive. Some scientists still lobby for a broader definition. assistant art director Chang Won Chang The debate over classifying solar system objects reminds me of another classifi- science news for students editor Janet Raloff cation challenge: categorizing the diversity of life on Earth. As a child, I remember managing editor Sarah Zielinski learning about the five kingdoms of life: animals, plants, fungi, protists (things assistant editor Maria Temming web producer Lillian Steenblik Hwang like algae) and monerans (bacteria). Though there was never a vote (that I’m society for science aware of), that system was superceded. In the 1990s, biologists proposed new president and ceo Maya Ajmera chief of staff Rachel Goldman Alper groups such as domains — bacteria, archaea (unicellular organisms that had once chief marketing officer Kathlene Collins chief program officer Michele Glidden been considered bacteria) and eukaryotes. More recently, scientists have debated chief, events and operations Cait Goldberg chief communications officer Gayle Kansagor how to organize eukaryotes, organisms that store DNA within a cell nucleus. For chief advancement officer Bruce B. Makous chief technology officer James C. Moore example, did you know you’re an opisthokont? According to some biologists, all chief financial officer Dan Reznikov animals, fungi and some single-celled eukaryotes fall into that “supergroup” board of trustees chair Mary Sue Coleman (SN: 8/8/15, p. 22). The name, roughly meaning “rear pole,” references the fact vice chair Martin Chalfie treasurer Hayley Bay Barna secretary Paul J. Maddon at large Christine Burton that many opisthokonts have at least some cells powered by a whiplike tail. Ani- members Craig R. Barrett, Adam Bly, Mariette DiChristina, Tessa M. Hill, Tom Leighton, Alan Leshner, W.E. Moerner, mals, for instance, have sperm. But I doubt many schoolchildren would cry if we Dianne K. Newman, Thomas F. Rosenbaum, Gideon Yu, lost our membership in this group, as they did over Pluto’s “demotion.” Feng Zhang, Maya Ajmera, ex officio advertising and subscriber services Categorizing life is an ongoing process, and even the definition of life itself advertising Daryl Anderson science news in high schools Anna Rhymes is uncertain, with questions about whether viruses should be considered permissions Maxine Baydush alive. Still, classification is more than just semantics. These groupings serve a Science News 1719 N Street NW, Washington, DC 20036 purpose; they reveal our place in nature and help us understand how life has (202) 785-2255 evolved. As new information, particularly genetic information, has come in, Subscriber services: scientists have realized that some groupings had been based on superficial­ sim- E-mail [email protected] Phone (800) 552-4412 in the U.S. or ilarities and have revised the taxonomy accordingly. 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Though this Science News (ISSN 0036-8423) is published 22 times per broader definition of a planet may never year, bi-weekly except the first week only in May and October In the next few months, and the first and last weeks only in July by the Society for various Science News editors be put to a vote, we’d love to know whether Science & the Public, 1719 N Street, NW, Washington, DC 20036. will share their thoughts in you think it’s a plausible alternative. Let us Subscribe to Science News: Subscriptions include 22 issues know at [email protected]. of Science News and full access to www.sciencenews.org and the Editor’s Note. cost $50 for one year (international rate of $68 includes — Erin Wayman, Managing Editor extra shipping charge). Subscribe www.sciencenews.org/subscription Single copies are $3.99 (plus $1.01 shipping and handling). 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2 SCIENCE NEWS | August 28, 2021

ed note.indd 2 8/11/21 2:15 PM Introduction to Astrophysics

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_p3.indd 3 7/29/21 4:04 PM notebook.indd 4 Page 20). Pluto toitsformerrank (see widely adopted,wouldrestore for theterm“planet”that,if proposed alternatedefinitions Some astronomershave since planet (SN:9/2/06,p.149 all — a downgrade todwarf the greatestdemotionof the planetreceived arguably scientists resolved Pluto’s heft, Earth’s mass.Decadesafter mass: about0.2percentof curately calculatetheplanet’s allowed astronomerstoac- ( Pluto’s moonCharonin1978 4 SCIENCE NEWS UPDATE: has noknown satellites. their motions.… ButPluto determined fromstudying has s atellites, itsmasscanbe suring itsmass.… Ifaplanet particular difficulties ofmea- mass ofPlutoillustrate the figures presentedforthe discrepancies amongthe its formerself.…Thewide mass, lessthananeighthof Pluto down to0.11 ofEarth’s est measurement] brings first todisappear.… [Thelat- make itlighter, itmay bethe If astronomers continueto ets tobediscovered (in1930). Pluto was thelast oftheplan- Pluto of mass shrinking The 50 YEARSAGO issue ofScienceNews August 28,1971 Excerpt fromthe NOTEBOOK SN: 7/15/78,p.36)finally The discovery of | August 28,2021 ). ). samples wouldhost atleast somelife,even per gram.Fiererassumedthatallofhis other regionshost atleast afewthousand of microbes, andAntarcticsoilsfrom typical soilcouldeasilycontainbillions Glacier wouldbedifferent.Aspoonfulof collected nearAntarctica’s Shackleton 204 soilsamples heandcolleagueshad gist Noah Fierertoexpectthatany ofthe (SN: 9/26/20, p. 10). have even survived foryearsinouterspace Mount Everest. Clumpsofmicrobialcells seafloor hydrothermal vents tohighon thrive everywhere fromboiling-hot microbes always seemtoget by. They Even intheharshest environments, Missing microbes hint at limits on the search for E.T. THE SCIENCELIFE life, anunexpected finding. seemingly devoid ofmicrobial Antarctica (shown)were near ShackletonGlacierin Some soilsamplescollected There was noreasonformicrobialecolo- released. shape when to itsoriginal spring back a curve and can bendinto image) scope in amicro- of ice(shown A tiny thread erties whensqueezed. — discovery couldgive researchersanew way tostudy ice’s prop- inducingtheiceto take onadifferentstructure.edge, That shape. Bendingthefibers compressestheiceonitsinside the bendingforce,fibers sprangbacktotheiroriginal with aradiusoftensmicrometers. Whentheteamreleased –150° Celsius, scientists could curve the ice into a partial circle giving thethreadsatypicalproperties. Between –70° and crystal. Buttheicethreadsconsisted ofnear-perfect c rystals, contains defects:tiny cracks, poresormisaligned sectionsof kers wereafewmicrometers indiameter orless. Ice usually water vaporwithinachilledchamber. Theresultingicewhis- applied toit,whichattracted a needlewithanelectricvoltage Z hejiang University inHangzhou,China,andcolleaguesused scientists reportintheJuly 9Science. be ruined.Thin,pristine threadsoficearebendyandelastic, Ice’s well-established reputation forbeingstiff andbrittle may experiments lab in flexible gets Ice HOW BIZARRE To createtheflexibleice,nanoscientist Peizhen Xu of Watch avideooficebendingatbit.ly/SN_IceSpring the searchforlifeonother planets. “The results shouldbeinterpreted, especiallyin questions abouthow negative scientific limit onmicrobialhabitabilityandraise cold andaridconditionsmightplaceahard to supportany kindofmicrobiallife. entists have foundsoilsthatdon’t appear knowledge, thisisthefirst timethatsci- Research: Biogeosciences.To Fierer’s report intheJune Journal ofG eophysical by microbes atall,Fiererandcolleagues d riest soilsdidn’t seemtobeinhabited damp laundryoutsidetofreeze-dry. is socoldandaridthatheoftenlefthis though theairaroundShackleton Glacier The findings suggest thatexceedingly Surprisingly, someofthecoldest, Emily Conover 8/11/21 11:31AM

FROM TOP: N. FIERER; P. XU ET AL/SCIENCE 2021

FROM TOP: ALMA/ESO, NAOJ AND NRAO, M. BENISTY ET AL; COURTESY OF N. FIERER challenge comes back to this sort of another method to try, he says. philosophical [question]: How do you Polar microbiologist Jeff Bowman prove a negative?” says Fierer, of the sees the findings as an indication that University of Colorado Boulder. current technology can’t detect very Proving a negative result is notori- low levels of life, which can lead to ously difficult. No measurement is false-negative results. “Certainly, there perfectly sensitive, so there’s always a were things there,” says Bowman, of the possibility that a well-executed experi- Scripps Institution of Oceanography in ment will fail to detect something that is La Jolla, Calif. “This is Earth. This is an actually there. It took nearly two years environment that is massively contami- of experiments based on multiple meth- nated with life.” ods before Fierer and his University of Even if there were a few microbes in Colorado colleague Nick Dragone finally the soil, that wouldn’t undermine the felt confident enough to announce that team’s evidence that cold and aridity PICTURE THIS though the air around Shackleton Glacier they’d found seemingly microbe-free pose a serious challenge to life, Dragone A forming exoplanet is so cold and so arid that he often left his soils. And the scientists intentionally says. “It’s the combination of multiple damp laundry outside to freeze-dry. stated only that they were unable to very challenging environmental condi- could make moons Surprisingly, some of the coldest, detect life in their samples, not that the tions that restricts life more than just d riest soils didn’t seem to be inhabited soils were naturally devoid of life. “We one acting by itself.” New images may provide by microbes at all, Fierer and colleagues can’t say the soils are sterile. Nobody As scientists search for evidence of the first view of moons forming out- report in the June Journal of G eophysical can say that,” Fierer says. There’s always life beyond Earth, they will be forced side the solar system. Research: Biogeosciences. To Fierer’s to walk the line between evidence The Atacama Large Milli meter/ knowledge, this is the first time that sci- Microbe-free soil of absence and absence of evidence. submillimeter Array, or ALMA, in entists have found soils that don’t appear samples raise questions “What we’re trying to do on is Chile glimpsed a dusty disk of poten- to support any kind of microbial life. about how to interpret kind of the reverse of what we’ve tried tially moon-forming material around negative results, says The findings suggest that exceedingly researcher Noah Fierer. to do on Earth,” says polar microbiolo- a baby exoplanet about 370 light- cold and arid conditions might place a hard gist Lyle Whyte of McGill University in years from Earth. The -like limit on microbial habitability and raise Montreal. On Earth, claiming that an world is surrounded by enough mate- questions about how negative scientific environment is lifeless is a tough scien- rial to make up to 2.5 Earth moons, results should be interpreted, especially in tific sell. On Mars, it will be the other researchers report in the July 20 the search for life on other planets. “The way around. — Elise Cutts Astrophysical Journal Letters. ALMA observed a planet dubbed PDS 70c circling the star PDS 70 HOW BIZARRE THE –EST (center, above) in July 2019. Unlike Ice gets flexible in lab experiments A skeleton unearthed in Peru vies for the title most known , this world is still forming, gobbling up material Ice’s well-established reputation for being stiff and brittle may of oldest known shark attack victim from the disk of gas and dust swirling be ruined. Thin, pristine threads of ice are bendy and elastic, When news broke in June that the oldest known case of a person killed by a shark around its star. During this forma- scientists report in the July 9 Science. involved a member of Japan’s Jōmon culture around 3,000 years ago (SN Online: tion process, planets are expected to To create the flexible ice, nanoscientist Peizhen Xu of 7/23/21), two researchers took special notice. wrap themselves in their own debris Z hejiang University in Hangzhou, China, and colleagues used Back in 1976, bioarchaeologist Robert Benfer of the University of Missouri in disks, which control how planets a needle with an electric voltage applied to it, which attracted Columbia and anthropological archaeologist Jeffrey Quilter of Harvard University pack on material and form moons. water vapor within a chilled chamber. The resulting ice whis- helped excavate a roughly 17-year-old boy’s skeleton at a Peruvian village site Around PDS 70c, ALMA spotted kers were a few micrometers in diameter or less. Ice usually called Paloma. The remains bore signs of a fatal shark encounter: One of the boy’s a disk of dust (small dot, right of the contains defects: tiny cracks, pores or misaligned sections of legs was missing, and his hip and forearm bones displayed deep bite marks char- star) about as wide as Earth’s orbit crystal. But the ice threads consisted of near-perfect c rystals, acteristic of those made by sharks. Radiocarbon dating indicated that the teen around the sun. With previously

giving the threads atypical properties. Between –70° and SCIENCE 2021 died around 6,000 years ago, Benfer says. That could make the teen the real oldest reported sightings still –150° Celsius, scientists could curve the ice into a partial circle known shark attack victim. controversial (SN Online: 4/30/19), with a radius of tens of micrometers. When the team released Quilter described the youth’s shark-related injuries in two paragraphs in the the new observations offer some of the bending force, the fibers sprang back to their original 1989 book Life and Death at Paloma. But the results were never published in an the best evidence yet that planets shape. Bending the fibers compresses the ice on its inside academic journal. Quilter and Benfer e-mailed the excerpt to the Jōmon research- orbiting other stars have moons. edge, inducing the ice to take on a different structure. That ers on July 26. “We were unaware of their claim until now but are keen to speak to — Maria Temming discovery could give researchers a new way to study ice’s prop- them about it in more detail,” says archaeologist J. Alyssa White of the University erties when squeezed. — Emily Conover XU ET AL / N. FIERER; P. TOP: FROM OF N. FIERER M. BENISTY ET AL ; COURTESY AND NRAO, NAOJ ALMA/ESO, TOP: FROM of Oxford, who led the Jōmon team. — Bruce Bower

Watch a video of ice bending at bit.ly/SN_IceSpring www.sciencenews.org | August 28, 2021 5

notebook.indd 5 8/11/21 11:32 AM LIFE & EVOLUTION Oldest animal fossil claim stirs debate News Squiggly alleged sponge hints at a much earlier start for animals

BY JAKE BUEHLER the Cambrian Period, when an extreme tubes in 1992 in rocks from Little Dal, an Pale, wormlike tubes in 890-million- burst in the evolution of animal diversity ancient reef system formed by cyano- year-old rock may be ancient sea sponges, began (SN: 9/7/13, p. 12). Some other ani- bacteria, in northwestern Canada’s a new study concludes. If confirmed, that mals are known from nearly 20 million Mackenzie Mountains. “I found this controversial claim would push back the years earlier, but go too much further thing that was totally out of place,” she origin of the earliest sponges by about back in time and the fossils’ classifica- says. “It was much more complex in 350 million years and make the micro- tion as animals becomes less certain terms of its structure than anything that scopic squiggles the oldest known fossils (SN: 4/4/15, p. 12). Based on genetic could be made by cyanobacteria.” of animals. data and sponges’ relative simplicity, the She would have reported the curious Crucially, these fossils would imply creatures are generally thought to have squiggles then, but without much else that animals emerged in environmental been the earliest form of animal life. to tie the fossils to sponges besides a conditions previously thought unwork- But some scientists aren’t convinced general resemblance, Turner moved on. able for animal life, geologist Elizabeth that the newly described tubes are More than a decade later, other scientists Turner reports July 28 in Nature. sponge fossils. “Organisms from any- published research showing that sponges Early in Earth’s history, the ocean where on the tree of life can make wiggly, preserved in rock could appear similar mostly lacked oxygen. It wasn’t until little [branching and rejoining] struc- to the pallid wiggles at Little Dal, so she about 800 million to 540 million years ago tures,” says paleobiologist Jonathan returned to her find. that a large pulse of the gas to the atmo- Antcliffe of the University of Lausanne Turner argues that many modern sphere, known as the Neoproterozoic in Switzerland. The fossils lack features sponges don’t have spicules. If ancient Oxidation Event, brought atmospheric such as mineralized skeletal parts called creatures were similar, the newly oxygen levels to within 10 to 50 percent spicules that would identify the crea- described fossils could be sponges. And of modern levels. That event boosted the tures as sponges, he says. she suggests that sponges predating the amount of oxygen in surface ocean waters What’s more, the finding doesn’t fit Neoproterozoic Oxidation Event may (SN: 1/18/20, p. 7). Until that point, oxy- with what scientists know about the have scraped out an existence in “o xygen gen levels were thought to be too low to availability of nutrients, biominerals oases” along microbial reefs, living in sustain animal life. “But sponges are dif- and oxygen in the whole ocean ecosystem holes and reef flanks. ferent from other animals,” says Turner, before the Cambrian Period, A ntcliffe It’s possible that early sponges of Laurentian University in Sudbury, says. “Everything we know about the emerged much earlier than the rest of Canada. “Some sponges in the modern Earth’s oceans in this interval of time animal life and remained in a kind of evo- world and in the rock record are known to tells us that animals originated around lutionary stasis in low-oxygen conditions, be tolerant of comparatively low oxygen 540 [million to] 550 million years ago. Turner says. The evolution of more com- relative to modern ocean levels.” It’s a legion of evidence, and to overturn plex animals would have had to wait until Until now, the earliest, unambigu- such an enormously strong paradigm, oxygen became more abundant. ous fossilized sponges date to about you need more than ‘might be a sponge.’ ” Scientists have known about odd types 540 million years ago to the beginning of Turner first found the network of of fossils in the Little Dal reef for a while, says paleobiologist James S chiffbauer of the University of Missouri in Columbia. And previous genetic analyses have sug- gested that sponges evolved well before the Cambrian Period. “It has just been a matter of finding them if they were indeed preserved,” Schiffbauer says. Future research could help confirm the fossils’ identity. Turner says she plans to continue studying the ancient tubes, add- ing that more answers may come from 100 µm 100 µm looking in the right places. “We need to be A skeletal fragment of a modern bath sponge (Spongia officinalis) has a characteristic branched looking for similar material with a really

structure. What’s claimed to be an ancient sponge fossil (inset) sports a similar structure. open mind in rocks of similar age.” s 2021 TURNER/ NATURE E.C.

6 SCIENCE NEWS | August 28, 2021

worm-fossil.indd 6 8/11/21 11:55 AM moon.indd 7

FROM TOP: RORY COTTRELL; T. PESQUET/ESA, NASA says: Themoonhasn’t a generated point tooneconclusion,theteam says. “How does thishappen?” one 2millionyearsago,” he moon now, and there wasn’t isn’t amagnetic field onthe because “everyone agreesthere Tarduno says. That’s odd, tle weaker than Earth’s today,” strong magnetic field, “just alit- about 2 hadmillion a years ago formed during ameteorite impact rocks werebarelymagnetized atall. 3.2 showed billionyearsago thatthose tals inrockdatingfrom3.9 billionto of tiny shardsofmetal trappedincrys- rock samples. Analyzingthemagnetism magnetization ofahandfultheApollo ing, hesays. sustained adynamoforlongbeforecool- It’s not clearhow thatcore could have U­ says geophysicist John Tarduno ofthe may have lasted hasbeenunclear. p. 17). Buthow longsuchalunardynamo ing rise to a magnetic field ( inside the core of acelestial body, giv which molten,iron-richrockswirls have once had an internal dynamo the first indicationthatthemoonmay by Apollo astronauts were decadesago Advances. in S­cience years ago, researchersreportAugust 4 netic field by was gone atleast 4 billion thatanymoon rockssuggest lunarmag- particles from thesun. Now, analyses of tive sheath that can deflect charged amagneticgenerating field, aprotec- 4.5 billionyearsago, itmay have begun a newstudy suggests. p­ A lunarmagnetic field may have BY CAROLYN GRAMLING The moon’s magnetic field lasted million 500 years at most Lunar rocks hint at fleeting magnetism ATOM &COSMOS ersisted for only a blip in geologic time, ersisted time, foronly a blip ingeologic niversity ofRochester inNewYork. Taken together, thesefindings But apieceoflunarglassthat Tarduno andcolleaguesexaminedthe The moon’s coreis“reallysmall,” Magnetized lunar rocks brought back Shortly afterthemoonformedabout SN: 12/17/11,

—

in - the moon’s magnetic field might have 1 billionyearsago, thathave suggested rock dating to between 2.5billionand analyses of the magnetization of a moon results fromrecents way theglassdid,Tarduno says. gotten theirmagnetization inthesame researchers have puzzledover may have highly magnetized lunar samples that 6/6/20, p. 32 tered by meteorites over time (SN: he says. acquired thatstrong magnetization,” as itwas moving throughthisplasma, thick, magnetized plasma.“Theglass, ionize particlesonthesurface,creating fast speeds, theimpactcanpartially punches intothelunarsurfaceatsuper studies, Tarduno says. Asameteorite has beendiscussedinpreviousscientific produce strong magnetization inrocks and colleaguessuggest. that also formed the glass itself, Tarduno happened due to themeteorite impact The magnetization ofthe bit ofglass magnetic field for at least 4 b­ at least4billionyears, astudysuggests. leaving itunprotectedfromthesolarwind,for Earth’s moonhaslacked amagneticfield, If so, thatmay alsohelpexplain The moonhasbeenrepeatedlybat- The ideathatameteorite impactcan ). Relatively young and ­tudies, based on illion years.

- tions may beabletomineforenergy, as are productsthatfuturemoonexpedi- soils (SN:5/11/19 &5/25/19, p. 8).Those -3 andwater buriedinthelunar may have leftahiddenwealthof surface by thesolarwindsincethen lengthy bombardmentofthemoon’s peared about4billionyearsago, the long-lived field.” “presents a well-argued case against a for theEarth.” Thenewstudy, she says, whereas youcandothatpretty easily enough oomphtomake amagnetic field, have agreatdealoftrouble generating eling studies of the moon’s core “just of Oceanography in La Jolla, Calif. Mod tist Lisa Tauxe oftheScrippsInstitution magnetic field atall,says paleomagne- of yearsoreven ifthemoonever hada sustained amagnetic field for billions how themoon’s smallcorecouldhave (SN:9/16/17,years ago p. 10). untilasrecently1billionlingered than amagneticfieldfromthemoon’s core. probably wasmagnetizedby theimpactrather about 2millionyears ago (example shown) Lunar glassthatformedinameteoritestrike well aslifesupport. exciting stuff.” If any lunar magnetic field disap- Geodynamicists have wrangledover any other way,” hesays. “That’s really www.sciencenews.org give scientists an unprecedented Drilling intothosesoilsmay also which you’re not to get in going glimpse at past physical properties and earlyEarth’s , of the sun, Tarduno says, which learn both abouttheancient sun could alsohelpscientists better “[We] have thepotential now to early Earth(SN:6/25/16, p. 12). understand conditionsonthe s | August28,2021 1 mm 8/11/21 12:06PM 7 - volcano-fossil-light.indd 8 8 SCIENCE NEWS the observation’s implications. qualify asreal,raisingquestions about Some physicists arguethe photons don’t onwhether thelight is “real.”hinges positron. Butthedetection’s significance tron anditsantimatter counterpart,a into oneanother andproduceanelec- two particlesoflight,orphotons, crash sought Breit-Wheeler process, inwhich the first direct observationofthelong- prisingly hardtoprove. simple idea,butitturnsouttobesur- matter and antimatter. It sounds like a Collide lightwithlight,andpoof,youget BY EMILY CONOVER whether the photons are ‘real’ But the result depends on matter making caught is Light MATTER &ENERGY eruption around1600B.C. causedpartof cano used to be above water, but a v iolent Sea. The entire vol- out of the Aegean ing thecentraltipofavolcano poking other volcanoes, theresearcherssay. sea levels probablysimilarlyinfluence volcanic systems areinornearoceans, report intheAugust Nature Geoscience. sea level, thevolcano isquiet, researchers a fit oferuptions. Duringtimesofhigher level dipsmorethan40meters, ittriggers 360,000 yearssuggests that when thesea volcano withsealevels over thelast ble. A comparison of the activity of the S antorini inGreecegets readytorum- p resent-day level, theisland volcano When sealevel dropsfarbelow the BY MARIATEMMING to periods of low sea level linked are flare-ups Santorini eruptionsvolcanic Sea level dips spur EARTH &ENVIRONMENT NEWS A teamofphysicists isnow claiming Santorini is a ring of islands surround- Since morethanhalfoftheworld’s | August 28,2021 balloon, wheretherubberisEarth’s crust wrapping yourhandsaroundaninflated splinter. Satow comparesthescenarioto magma chamberwouldcausethecrust to lowering theamountofwater atopthe close, stopping eruptions. cracks shouldtake about11,000 yearsto found. After the water rises again, the face andawaken the volcano, theteam take about13,000 yearstoreachthe sur- of OxfordBrookes University inEngland. make itsway tothesurface,” says Satow, to “move upthroughthese fracturesand allows magma stored under the volcano splintered, thesimulationshowed. That level, thecrust above themagmachamber at least 40meters below thepresent-day no’s surface. Whenthesea level dropped about four kilometers beneath the volca- S antorini’s magma chamber, which sits created acomputersimulationof pher Christopher Satow andcolleagues influence thevolcano, physical geogra- (SN: 3/10/12, p. 12). the volcano tocave in,formingalagoon in E instein’s equation E=mc stration ofthephysics immortalized of Brookhaven. It’s astriking demon- interesting concept,” says Brandenburg, ter fromlightsmashingtogether isan the July 30Physical ReviewLetters. B randenburg and colleagues report in sive transformation,physicist Daniel New York match predictionsfortheelu- Brookhaven National Laboratory in ments fromtheSTAR experimentat been directlyobserved. Newmeasure- the Breit-Wheeler processhadnever don’t carrytheirnormalmasses. ones that appear for only instants and In particlephysics, virtualparticlesare the Breit-Wheeler process, or “virtual.” are considered“real,” asdemandedby fies depends on whether the photons sides ofthesame coin. revealed that energy and mass are two It may seemcounterintuitive that Those magma-filled cracksshould To investigate how sea level might “The ideathatyoucancreatemat- Predicted more than 80 years ago, Whether theobservationtrulyquali- 2 , which suggesting thatthe team had seen the matched expectations for real photons, whether realor virtualphotons collided, those particles, which depend on spit outoneelectronandpositron. So theteamlooked fornear-misses that two photons fromthosefields cancollide. their electromagnetic fields overlap and where thenucleibarelymissoneanother, the twonucleiarezippingalong.Incases are realduetothehighspeedsatwhich experiment, thephotons actasifthey tromagnetic fields arevirtual.Butinthe Relativistic Heavy Ion Collider. nuclei thatracearoundB rookhaven’s the electromagnetic fields oftwoatomic collided camefromanunusualsource: up for debate because the light the team B randenburg and colleagues’ photons are considered real. But thebonafides of light, suchasalightbulborlaser, are predictions by comparingSantorini’s and ultimatelytheballoonbreaks. the balloon starts toexpand,” Satow says, takingthesealevel down,hands, [like] start toreleasethepressurewithyour balloon frompopping.“As soonasyou ofyourhandshelpsprevent the building upunderEarth’s crust — the pumps airintotheballoon — like magma weight oftheocean.Assomeoneelse and yourhands’inward pressureisthe els arehistoricallylinked tomoreeruptions. (shown fromabove) inGreece.Lower sealev- the partiallysubmergedvolcano ofS antorini Sea level seemstoinfluenceeruptionsfrom Measurements ofangles between Normally, photons fromsuchelec- Photons fromacommon sourceof The teamtested thesimulation’s 8/11/21 12:08PM

NASA EARTH OBSERVATORY

MARK WITTON light makingmatter. hoping, willclinchthecasefor colliding to readthisarticle.That,physicists are that’s asrealthelight allowing you process withlasers, which produce light toward detecting the Breit-Wheeler still virtualby somedefinitions. However, Mangles says, thephotons are about itmakes itlooklike a realphoton.” London. “Everything they’re measuring S tuart Mangles of Imperial College that up, says laser plasma physicist the photon isbasedonhow itbehaves. different view, inwhichtherealityof as ifreal,theyaretechnicallyvirtual. Oxford. Whilethephotons behave almost Lucian Harland-LangoftheUniversity of Wheeler process, says particle physicist one step removed fromthetrueBreit- Breit-Wheeler process. lent eruptions aren’t offthetable. sea levels, theteamsays, sofuturevio- volcano’s history didhappenamidhigh quiet. Buttwomajoreruptions inthe the volcano toenteraperiodofrelative mate change — so Satow’s teamexpects age — and sealevel isrisingduetocli- day level was neartheendoflast ice level was 40meters below thepresent- volcanic systems oftheweightice. lying glaciershave melted,relievingthe shown an uptick in eruptions after over- Icelandic volcanoes, forinstance, have inEugene. of theUniversity ofOregon state,” says geophysicist EmilieHooft in their stressare sensitive to changes other studies have shown thatvolcanoes and perhapsnot surprising,given that up inglaciersduringiceages. when moreofEarth’s water was locked Such periodsoflow sealevel occurred periods oflow sealevel, aspredicted. the last 360,000 yearshappenedduring volcano’s 211well-datederuptions in of past sealevels. Allbutthreeofthe e ruption history evidence withgeologic Mangles and others are working The scientists’ measurementsback Brandenburg andcolleaguestake a Strictly speaking,theexperimentis As for Santorini, the last time sea “It’s reallyintriguingandinteresting, s s eruption history with geologic evidence LIFE & EVOLUTION of past sea levels. All but three of the volcano’s 211 well-dated eruptions in Newly hatched pterosaurs took flight the last 360,000 years happened during A strong wing bone suggests the baby reptiles were agile fliers periods of low sea level, as predicted. Such periods of low sea level occurred BY CAROLYN GRAMLING flight are strong bones, sufficient muscle when more of Earth’s water was locked Pterosaur hatchlings may have been able mass to stay in the air for a long time and up in glaciers during ice ages. to fly right out of the shell. A new analysis sturdy keratin fibers in the skin of the “It’s really intriguing and interesting, of the fossilized wing bones of embryonic, wings, analogous to bird feathers, Padian and perhaps not surprising, given that newly hatched and adult pterosaurs sug- says. “We know little about the last two.” other studies have shown that volcanoes gests the baby creatures were strong and Paleontologist Darren Naish of the are sensitive to changes in their stress nimble fliers from the start, researchers University of Southampton in England state,” says geophysicist Emilie Hooft report July 22 in Scientific Reports. and colleagues turned to bones, com- of the University of Oregon in Eugene. Pterosaurs were a diverse group of paring fossilized embryo and hatchling Icelandic volcanoes, for instance, have flying reptiles that lived alongside dino- wing measurements with those of adults shown an uptick in eruptions after over- saurs from 228 million to 66 million from two species: Pterodaustro guinazui lying glaciers have melted, relieving the years ago during the Triassic and and S inopterus dongi. The team zeroed volcanic systems of the weight of the ice. Cretaceous periods. The group includes in on one wing bone, the humerus, that As for Santorini, the last time sea Quetzalcoatlus northropi, the larg- offers key information on whether a level was 40 meters below the present- est creature known to take wing, and pterosaur was capable of getting off the day level was near the end of the last ice K unpengopterus antipollicatus, which ground. age — and sea level is rising due to cli- had opposable thumbs that enabled it to Relative to hatchlings’ size, their mate change — so Satow’s team expects climb trees (SN: 5/8/21 & 5/22/21, p. 16). humerus bones were stronger than those the volcano to enter a period of relative Scientists know relatively little about of many of the adults, and hatchlings also quiet. But two major eruptions in the whether young pterosaurs could actively had shorter, broader wings, suggesting volcano’s history did happen amid high flap their wings or only glide — which that youngsters might have been capable sea levels, the team says, so future vio- might mean they stayed under paren- of nimbly changing direction and speed, lent eruptions aren’t off the table. s tal care until they were flight-ready. But and possibly flying long distances. Agile relatively recent revelations increasingly flying may have helped the hatchlings point toward early independence, or pre- escape predators and chase tricky prey Breit-Wheeler process. cociality, for the reptiles. For instance, such as insects, all while navigating Strictly speaking, the experiment is researchers have found flight mem- dense vegetation, the team suggests. one step removed from the true Breit- branes on the wings of an embryonic It isn’t unusual in the animal world Wheeler process, says particle physicist pterosaur and the remains of a juvenile for young to fend for themselves, Padian Lucian Harland-Lang of the University of that was capable of long-distance flying says. “Precociality is the rule, not the Oxford. While the photons behave almost long before it had grown to adult size. exception, in vertebrates,” he says. as if real, they are technically virtual. “Baby pterosaurs almost certainly Only animals with extended parental Brandenburg and colleagues take a didn’t glide,” they flew, says paleontolo- care, such as songbirds and primates, different view, in which the reality of gist Kevin Padian of the University of can afford to be helpless for prolonged the photon is based on how it behaves. California, Berkeley. The three keys to periods. s The scientists’ measurements back that up, says laser plasma physicist A flamingo-like pterosaur, Pterodaustro guinazui S tuart Mangles of Imperial College (shown in this artist’s rendition), could fly from the moment it emerged from its shell, London. “Everything they’re measuring new research suggests. about it makes it look like a real photon.” However, Mangles says, the photons are still virtual by some definitions. Mangles and others are working toward detecting the Breit-Wheeler process with lasers, which produce light that’s as real as the light allowing you to read this article. That, physicists are hoping, will clinch the case for colliding

NASA EARTH OBSERVATORY NASA EARTH MARK WITTON light making matter. s

www.sciencenews.org | August 28, 2021 9

volcano-fossil-light.indd 9 8/11/21 12:09 PM NEWS

When the Chicxulub asteroid (illustrated) slammed into Earth millions of years ago, the impact formed a tsunami that may have left ripples in rock under present-day Louisiana.

there should be a tsunami.” The ripple marks were preserved all this time thanks to the depth at which they formed underwater, K insland says. Other studies suggest that this region was 60 meters below the sea surface at the time. At that depth, the ripples would have been beyond the reach of tumultu- EARTH & ENVIRONMENT ous storms that could have erased them. Then, over millions of years, other sedi- Dino-killing asteroid had a ripple effect ments slowly buried the marks. An impact-induced tsunami may have left behind giant ridges A smaller, analogous set of struc- tures may exist off the east coast of BY NIKK OGASA which was underwater at the time Japan. There, a repeating sequence of The asteroid impact that slew the dino- (SN: 11/25/17, p. 14). But no one had ever u nderwater dunes was reported to have saurs may have also indirectly sculpted before found ripple marks formed by the appeared after the 2011 Tohoku earth- the largest ripple marks ever found on sprawling wave. quake and tsunami (SN: 2/25/12, p. 22). Earth. Geologist Kaare Egedahl discovered Except for the dunes’ size, they look A series of ridgelike structures more the ripples while searching for coal nearly identical to the ripple marks than three stories high and spaced deposits. Studying at the University buried beneath L ouisiana, K insland nearly two Eiffel Towers apart appear of Louisiana at Lafayette at the time, says. That supports the idea that the to be buried about 1.5 kilometers E gedahl had been combing through taller structures were also produced by beneath central Louisiana. The over- seismic reflection data — 3-D images of a tsunami, though one of a much larger sized features are megaripples shaped buried rock and soil that were generated magnitude. by a massive tsunami generated by the by underground sound waves — provided Still, there is contention over whether Chicxulub asteroid impact, researchers by the Devon Energy company. Egedahl, the features beneath Louisiana really are argue in the Sept. 15 Earth and P lanetary now at the oil and gas company Cantium megaripples formed by the Chicxulub- Science Letters. in Covington, La., found the ripples atop induced tsunami. “It’s just interesting that something a layer of rock thought to have formed “It’s hard to see how such a high- that happened 66 million years ago could from debris shaken up by the Chicxulub energy event could form ripple marks be so well preserved, buried 5,000 feet asteroid impact. He then shared his find- because they are usually associated down in the sediments of L ouisiana,” ing with Kinsland. with much calmer environments,” says says geologist Gary Kinsland of the “I knew where that layer was from sedimentologist Pedro J.M. Costa of U niversity of Louisiana at Lafayette. in geologic time, and I knew what hap- the University of Coimbra in Portugal. Ripple marks are repeating sequences pened there,” Kinsland says. “I knew And ripple marks typically form from of ridges typically found on sandy frequent and recurring wave motion, beaches or stream bottoms and form These are the ripples (most pronounced near while tsunamis don’t have many waves, as wind or water flows over and moves the red line in this reconstruction) beneath he explains. Costa, who studies tsunami Louisiana that a group of geologists say were loose sediment. But ripple marks on the created by an asteroid-induced tsunami. deposits, says that reconstructing the lay beach are often centimeters in height, of the seafloor at the time of the impact while the structures found by Kinsland’s 11.3 km and conducting experiments in water- team have an average height of 16 meters filled wave tanks could help unravel and are spaced about 600 meters apart. the origins of the structures found by 17.7 km The structures’ shape, size, ori- Kinsland’s team. entation and location suggest that This new work is important because they formed after the Chicxulub it opens a discussion, Costa says. Maybe asteroid crashed into the Yucatán the Chicxulub impact “was such a high- Peninsula in Mexico, generating a tsu- magnitude event that what we see in nami that washed across the Gulf of normal tsunami events don’t apply to

Mexico and what is now Louisiana, this one.” s STRONG MARTELL IMAGES; LIBRARY/GETTY MARK GARLICK/SCIENCE PHOTO TOP: FROM

10 SCIENCE NEWS | August 28, 2021

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_p11.indd 11 7/29/21 4:07 PM NEWS

LIFE & EVOLUTION insect virologist Madoka Nakai of the instructions from another host Tokyo University­ of Agriculture and remains unclear, he says. Sick caterpillars T­echnology. A parasitoid wasp would kill Researchers discovered in the 1970s a host that the virus needs to survive, so that virus-infected caterpillars could keep wasps at bay the virus fights for its home. “It’s very kill parasitoid wasp larvae using an Viruses stop young moths clever,” Nakai says. unknown viral protein. In the new study, from becoming wasp nurseries What’s more, some moth caterpillars Herrero, Nakai and colleagues identi- make the wasp-killing proteins them- fied PKF as wasp-killing proteins. The BY ERIN GARCIA DE JESÚS selves, the team found. It’s possible that team infected moth caterpillars with When parasitic wasps come calling, in the distant past, a few moths survived a one of three insect viruses that carry some caterpillars have a surprising ally: viral infection and “got some presents” in the genetic blueprints to make the a viral infection. the form of genetic instructions for how proteins. Then the researchers either Insects called parasitoid wasps lay to make the proteins, says insect pathol- allowed wasps to lay their eggs in the their eggs inside young moth larvae, ogist and geneticist Salvador Herrero caterpillars or exposed wasp larvae to turning the caterpillars into unwitting, of the U­niversity of Valencia in Spain. hemolymph — the insect equivalent of destined-to-die incubators for possibly Those insects could have then passed blood — from infected caterpillars. hundreds of wasp offspring. That’s bad the ability on to offspring. In this case, Virus-infected caterpillars were poor news for viruses trying to use the cat- “what doesn’t kill you makes you stron- hosts of the parasitoid wasp Cotesia erpillars as replication factories. Viral ger,” Herrero says. k­ariyai. Most young wasps died before infections can be lethal for the caterpil- Previous studies had shown that they had the chance to emerge from the lars, but their chances of surviving with viruses and insects, including moths, caterpillars into the world. Hemolymph a virus are probably higher than if wasps can swap genes with each other. The new from infected caterpillars was also an use them as a living nursery. finding is one of the latest examples of efficient killer of wasp larvae, typically Now, a study shows how certain this activity, says entomologist Michael destroying more than 90 percent of viruses can help caterpillars stymie Strand of the University of Georgia in offspring.­ parasitoid wasps. A group of proteins Athens who was not involved in the C. kariyai wasp larvae also didn’t dubbed parasitoid killing factor, or PKF, research. survive in caterpillars, including the that is found in some insect viruses are “Parasite-host relationships are very beet armyworm (Spodoptera exigua), incredibly toxic to young parasitoid specialized,” Strand says. “Factors like that make their own PKF. When the wasps, researchers report in the July 30 [PKF] are probably important in defin- researchers blocked the genes for the Science. ing which hosts can be used by which proteins in these caterpillars, the wasps The finding shows that viruses and parasites.” But whether caterpillars stole lived, a sign that the proteins are key for caterpillars can come together to the genetic instructions for the proteins the caterpillars’ defenses. fight off a common wasp enemy, says from viruses or viruses originally­ stole Some parasitoid wasps, including Meteorus pulchricornis, weren’t affected Some moth caterpillars, such as beet armyworms (one by PKF from the viruses or the beet army- shown), possess viral proteins that kill the larvae of worms, allowing the wasp offspring to p­arasitoid wasps incubating inside them, a study finds. thrive inside caterpillars. That finding suggests that the wasp-fighting ability is species specific, says Elisabeth Herniou, an insect virologist at CNRS and the U­niversity of Tours in France who was not involved in the work. Pinpointing why some wasps aren’t susceptible could reveal the details of a long-held evolu- tionary battle between all three types of organisms. The study highlights that “single genes can interfere with the outcome of [these] interactions,” Herniou says. “One virus may have this gene and the other virus doesn’t have it,” and that can change what happens when virus, cater-

pillar and parasitoid all collide. s 3.0 US) BY-NC (CC BUGWOOD.ORG OF FLORIDA, JOHN CAPINERA/UNIV.

12 SCIENCE NEWS | August 28, 2021

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_p13.indd 13 8/11/21 1:58 PM NEWS

decisions, the researchers found some- thing interesting: Branch flexibility had about six times as great an influence on when squirrels decided to jump as did the length of the gap. If squirrels had cared more about distance, they would have jumped from about the same spot on the rod, regardless of its give. “We were surprised to see squirrels weighing both of these things simul- As they jump, fox squirrels taneously, but in different amounts,” make quick Hunt says. calculations to The researchers upped the ante for five balance trade-offs between tree limb squirrels by increasing the flexibility of flexibility and distance branches as well as gap distance. Initial between limbs. leaps were less than graceful. No squirrels fell, but most had clunky landings at first, LIFE & EVOLUTION environments to navigate,” says Hunt, grasping the peg they leaped to with their an integrative biologist at the University front paws and swinging around to pull Leaping squirrels of Nebraska Omaha. themselves up instead of landing neatly When jumping between bendy on all fours. But within five trials, “squir- use parkour tricks branches, a squirrel must assess how far rels learned to compensate for their Obstacle course reveals how it has to jump and know when to leap as initial error,” Hunt says, which they did the animals navigate jumps it moves along a branch. Jump too early by modifying their initial velocity. and the squirrel will fall short. Too late, If squirrels regularly encounter the BY JONATHAN LAMBERT and the squirrel will find itself out on a same branches, such quick learning Parkour enthusiasts need look no fur- part of the branch too flimsy from which “might explain how they move so fluidly ther than up in the trees for inspiration. to launch. Hunt wondered, “How are and rapidly” across particular branches, Squirrels’ aerial acrobatics make the they sensitive to that trade-off, manag- Hunt explains. The rodents might be rodents masters of the form. ing to make accurate leaps?” such quick navigators, he says, because A detailed look at how squirrels navi- To find out, he and colleagues “they’ve already learned what they need gate narrow branches that bend and designed an artificial forest obstacle to know about that branch.” sway with the wind — where the smallest course on the outskirts of the University The squirrels surprised the research- error could spell death — shows that the of California, Berkeley campus. Then the ers in other ways too. For longer jumps, rodents make split-second calculations team used peanuts to coax free-ranging or those that necessitated landing higher to balance trade-offs between branch fox squirrels (Sciurus niger) into run- or lower than the starting point, many bendiness and the distance between tree ning and jumping through a series of squirrels rotated midair, using their legs limbs. And for particularly tricky jumps, acrobatic tests. to “jump” off an adjacent vertical wall in squirrels improvise parkour-style moves First, the unwitting subjects learned a parkour-style maneuver. More often to stick the landing, researchers report to leap from artificial branches of high, than not, squirrels employed parkour in the Aug. 6 Science. medium or low stiffness across a gap to to slow down if they were coming in too This research is “a great example reach a prize: a peanut at the end of a hot to a landing. “It’s an additional point of how cool ‘normal’ animals can be landing peg. High-speed video captured of control,” Hunt says. in their biomechanics,” says Michelle details of the jumps, from launch point For many arboreal animals, “jumping Graham, a biomechanist at Virginia Tech to landing accuracy, for 12 squirrels between limbs is such a common thing, in Blacksburg who was not involved with spanning 96 leaping trials. and yet we so frequently only study it in the work. “We’ve all seen squirrels do Unsurprisingly, the squirrels leaped pieces,” Graham says, such as looking crazy stuff in nature, but no one ever from more bendy branches earlier — just at the launch but not the landing. pays any attention to it.” presumably to maximize jumping This study’s holistic look reveals “some- That is unless you’re like Nathaniel force — even though that increased the thing really interesting about squirrels, Hunt, who has been mesmerized by distance that the animals must clear, that they take greater account of [branch watching squirrels flash through the Hunt says. By comparing what the bendiness] than the gap distance,” she overstory since graduate school. “Tree squirrels actually did with statistical notes. “I don’t know that I would’ve

canopies are incredibly challenging models that simulated optimal jumping guessed that.” s JINN/UC BERKELEY JUDY

14 SCIENCE NEWS | August 28, 2021 Watch squirrels leap through an obstacle course at bit.ly/SN_Squirrels

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_p15\.indd 15 7/29/21 4:20 PM NEWS

LIFE & EVOLUTION This sculpture in the Polar bears kill prey with ice and stone Itsanitaq Museum in A study supports Inuit accounts of bears clobbering walruses Churchill, Canada, depicts a polar bear lifting a block of ice BY GLORIA DICKIE S cience Lab at the University of Alberta above the head of a Walruses, weighing more than in Edmonton, Canada, who wasn’t sleeping walrus. 1,300 kilograms with huge tusks and involved with the research. He suspects nearly impenetrable skulls, are almost that it might be just a few polar bears impossible for a hungry polar bear to kill. that behave this way. For example, if a But some polar bears have invented a mother bear figured out how to use ice or work-around — bashing walruses on the stone to bludgeon prey, “it’s something head with a block of stone or ice. her offspring would pick up on,” but not For more than 200 years, Inuit in necessarily a skill polar bears across the Greenland and the eastern Canadian Arctic would acquire, Derocher says. Arctic have told stories of polar bears Among animals, using tools to solve (Ursus maritimus) using such tools to aid problems has long been regarded by sci- in killing walruses. Yet explorers, natu- entists as a marker of a higher level of ralists and writers often dismissed such intelligence. Chimpanzees, for example, young seals closer to them by pretend- accounts, relegating them to myth along craft spears to hunt smaller mammals ing to be asleep in open water. Other with tales about shape-shifting bears. (SN: 3/3/07, p. 131). Dolphins carry times, he’s observed a polar bear sniff The persistence of these reports, marine sponges on their beaks to stir out a seal’s breathing hole in sea ice, even including one from an Inuit sand and uncover prey (SN: when the hole was obscured by snow. hunter in the late 1990s, cou- “We have a 6/11/05, p. 371). And ele- “I have worked with the Inuit on tra- pled with photos of a male great deal of phants have been known to ditional knowledge for a very long time polar bear named GoGo at a observational drop logs or large rocks onto and one of my favorite subjects is polar Japanese zoo using tools to information electric fences to cut off the bears, because science often suggests obtain suspended meat, com- power supply. one thing and the Inuit say another pelled polar bear biologist that tends to Studies on the cognitive thing,” Nirlungayuk says. Ian Stirling and colleagues suggest polar abilities of polar bears are There are about 26,000 wild polar to investigate further. bears are lacking. “However, we have bears living in 19 subpopulations across “It’s been my general really smart.” a great deal of observational the Arctic and sub-Arctic. The bears observation that if an expe- information that tends to primarily eat seals, hunting the marine rienced Inuit hunter tells IAN STIRLING suggest polar bears are really mammals by staking out above their you that he’s seen something, it’s worth smart,” Stirling says. breathing holes. Because of climate listening to and very likely to be correct,” Members of the bear family, Ursidae, change, Arctic sea ice is fast disappear- Stirling says. are typically assumed to have strong ing, and scientists predict that many The researchers reviewed historical cognitive skills as a result of their large polar bear populations will be extinct by observations of tool use in polar bears brains and evidenced by their sophis- the century’s end. Desperate polar bears reported by Inuit hunters to explorers ticated hunting strategies. Studies on may increasingly attack walruses, but and naturalists; relatively recent obser- captive American black bears (Ursus “there are limitations to how many wal- vations by Inuit hunters and non-Inuit americanus) have even revealed some ruses an adult bear can take down,” says researchers; and documented observa- mental capabilities that appear to exceed study coauthor Kristin Laidre, an Arctic tions of GoGo and polar bear relatives in those of nonhuman primates. ecologist at the University of W ashington captivity using tools to access food. Taken Gabriel Nirlungayuk, an Inuit hunter in Seattle. It takes a lot of energy. together, the evidence suggests that tool of Rankin Inlet in Nunavut, Canada, says After the study was published, Anthony use in wild polar bears, though infre- he has heard such stories of polar bears Pagano, a U.S. G eological S urvey scientist quent, does occur in the case of hunting using tools to hunt walruses. “I’ve seen who is based in A nchorage, Alaska, sent walruses because of the walruses’ large polar bears since I was probably 7 years Stirling a video. Pagano had previously size, the team reports in the June Arctic. old. I’ve been around them, I’ve hunted attached a GoPro camera to a wild polar “Really, the only species you would alongside them, and I have seen their bear for a separate project. That footage, want to bonk on the head with a piece behaviors. The smartest hunters are Stirling says, shows a female polar bear of ice would be a walrus,” says Andrew usually the female bears.” Sometimes, sliding a large block of ice around before

Derocher, director of the Polar Bear Nirlungayuk says, polar bears will lure throwing it into the water at a seal. s G. DICKIE

16 SCIENCE NEWS | August 28, 2021

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_p17.indd 17 7/29/21 4:23 PM briefs.indd 18 18 SCIENCE NEWS the lungs. to keeping thevirusfromlodgingdeepin son’s airway, destroying acrucialbarrier forests ofhairlike ciliathatcoataper- A coronavirus infectioncanmowdown How COVID-19 sabotagescells GENES &CELLS up. breached thesurfacebeforestarblew from astar’scollapsingcorehadbarely because jetsthatradiate gammarays GRB. Theburstmay have beensobrief the stellarexplosion thatfollowedthe Gemini NorthTelescope inHawaii tofind of MarylandinCollegePark, usedthe Tomás Ahumada-MenaoftheUniversity stars butnotneutronstarmergers. astronomers expect tofinddyingmassive middle ofastar-forminggalaxy, where leagues say. Andthebursthailedfrom University ofNevada, LasVegas andcol- bursts, astrophysicist BingZhangofthe related GRBsthancollision-produced the burstweremoresimilartocollapse- light andamountofenergyreleasedin from theburstitself. Thewavelengths of studies inNature Astronomy. stars, researchersreportJuly26intwo actually befromthedeathsofmassive as originatingfromstellarmergersmay that someburstspreviously classified burst fromastellarexplosion suggests longer thantwoseconds. cally thoughttoproduceGRBsthatlast the starexploded. Thatprocessistypi- collapse ofamassive star’scorebefore the burstrevealed thatitcamefromthe ( originate fromneutronstarsmashups bursts, orGRBs,areusuallythoughtto August 2020.Suchfleetinggamma-ray gamma rays, dubbedGRB200826A,in detected aone-second-longblastof such especiallybriefcelestialcataclysms. astronomers rethinkingwhattriggers A surprisinglyshortgamma-ray bursthas expectationsastronomers’ A super-shortcosmicburstdefies ATOM &COSMOS NEWS INBRIEF ). But a closer look at SN: 11/11/17,p.6).Butacloserlookat Another group,ledby astronomer Clues abouttheGRB’sorigincame Discovering suchabriefgamma-ray The Fermi Gamma-ray SpaceT elescope — Maria Temming— Maria | August 28,2021 — Erin Garcia deJesús mucus throughtherespiratory tract. still — a signthatthecellswouldn’t move m ovement, thosebeadslargelystayed of infectedcellstomeasuremucus added microscopicbeadstothesurface cilia onhealthy cells.Whentheteam cells’ ciliawerestubby comparedwith tract withthecoronavirus. Infected that mimictheliningofrespiratory Paris infectedlab-grownhumancells report July16inNature Communications. cause severe COVID-19, researchers could helpthevirusinvade thelungsand structures stopmoving mucus,which tracts ofcilia.Cellswithoutthehairlike that systemoutofwhackby clearing which isthenswallowed. 10/24/20, p.7) — get stuckinmucus, like thecoronavirus (SN:10/10/20 & don’t belong — including viral invaders throat. To protectthelungs,objectsthat mucus outoftheairway andintothe The magnetic field lines that map out the The magneticfieldlinesthatmap outthe black hole’s magneticfieldtoescape. called magneticreconnectionallows the sity andcolleaguesfoundthata process Ashley Bransgrove ofColumbiaUniver- a magnetizedblackhole,astrophysicist holes wouldlosetheirhair. scientists didn’t knowwhethersuchblack cally chargedmattercalledplasma,and would typicallybesurroundedby electri- slip away. Butamagnetizedblackhole vacuum, wheremagneticfieldscansimply off. Thatincludesmagneticfields. other features,or“hair,” arequicklycast rule knownastheno-hairtheorem,any spin andelectriccharge.Accordingtoa They arecharacterized onlyby theirmass, isolated blackholesaremostlyidentical. discard theirmagneticfields. simulations reveal howblackholesmight black holeshave toshed.Newcomputer Like ashaggydoginspringtime,some Magnetized blackholesgobald ATOM &COSMOS Scientists atthePasteur Institute in But thecoronavirus appearstothrow Cilia normallymove inwaves topush In simulating the plasma surrounding In simulatingtheplasmasurrounding The ruleappliestoblackholesina Unlike dogswiththeirvariedfurcoats, LIFE &EVOLUTION Conoverlosing itshair. —Emily entists may oneday glimpseablackhole that astronomerscoulddetect.Sosci- the July30Physical ReviewLetters. hole’s magneticfield,theteamreportsin hole. Thatprocesseliminatestheblack outward whileothersfallintotheblack blobs ofplasma,somewhichblast nect. Loops ofmagneticfieldformaround field’s directionbreakapartandrecon- — Jonathan Lambert pays offforpikas.—Jonathan be seen,butclearly, notbeingtoopicky such mealshave downsidesremainsto pikas commonlydineondung.Whether from stomachcontentsconfirmedthat on thesurface,hesays. DNAevidence food source,reducingpikas’timespent in Scotland.Yak poopcouldbeaplentiful Speakman oftheUniversity ofAberdeen burrows,” says ecophysiologist John of half-eatenyakturdinonethe the researchers“untilwefoundasort abundant butforaged less. Thatpuzzled bodies acoupledegreesovernight. 29.7 p ercent, inpartby coolingtheir their metabolismby anaverage of in wintermonths,theanimalsslowed and bodytemperature revealed that And dataonpikas’energyexpenditure pikas regularlybrave thecoldtoforage. unusual rations: yakpoop. . Somepikaseven Sciences resortto of Proceedings NationalAcademy ofthe energy, researchersreportintheJuly 27 but reducetheirmetabolismtoconserve (Ochotona curzoniae)continueforaging on theQinghai-Tibetan Plateau,pikas stores ofgrass inburrowsduringwinter Instead ofhibernatingorsubsistingon Yak scathelpspikassurvive winter it easierforpathogenstoreachthelungs. micrograph) cutscells’cilia(purple), making The coronavirus (yellow inthisfalse-color The phenomenoncouldspewX-rays At siteswithyaks,pikasweremore Cameras atfoursitesconfirmedthat 8/11/21 12:04PM

VINCENT MICHEL, RÉMY ROBINOT, MATHIEU HUBERT, OLIVIER SCHWARTZ AND LISA CHAKRABARTI/INSTITUT PASTEUR my faItH inSpires me to loOk at tHe cHalLenGes in tHe worLd witH inNovatiOn, purPose, anD hope. | seE enDlesS opTiOnS for cReAtivity in pRobLem-solVinG anD usinG tHe powerFul toOlS of tHe sCiEnCes anD tecHnology! How doEs yOur faItH fuEl yOur sCiEnTific inQuIry? |’m witH yOu, dude. But rigHt now | jusT have one quEsTiOn: Are yOu, like, a “seA-horSe” or…??

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_p19.indd 19 7/29/21 4:25 PM pluto.indd 20 Pluto’s 20 SCIENCE NEWS a dwarfplanet. was reclassifiedas 15 years afterit planetary status, should re-earnPluto fascinating geology maintain that Some scientists ESSAY | August 28,2021 F 3) have clearedtheneighborhood arounditsorbit 2) have enoughmasstobespherical (orclose)and new definition requiredthatabody1)orbitthesun, new definition of “planet” that left Pluto out. The International Astronomical Union,orIAU, wrote a ular uproarwhen15yearsago, inAugust 2006, the museum’s planetarium. Likewise, therewas apop- hate mailtoNeildeGrasseTyson, directorofthe in New York City, childrensent display in2000attheAmericanMuseumof marginal existence asamisfit.” The Planets.“Adults relatetoitsinadequacy, its science writer Dava Sobel in her 2005 book was ourweirdo. tilted, eccentric orbit. Pluto was aweirdo, but it When Plutowas excluded fromtheplanetary “Children identifywithits smallness,” wrote half itssize.Noonemindedthatithada of thesolarsystem, withamoon,Charon, planet. Noonecaredthat itwas therunt or 76 years, Plutowas thebeloved ninth Place Place writing about Pluto since my very first newspaper objects, ofgreatimportance andinterest.” it as[a]prototype ofanewclasssolar system to demote Pluto, but onthecontrarytopromote were beingdiscovered. The intentionwas not atall planets asmoremassive [objectsbeyondNeptune] cult tokeep changingthenumberofsolarsystem system planets, anditwouldhave beenvery diffi- 2006. “Plutoisvery differentfromtheeightsolar Saclay inFrance, whowas president oftheIAU in one,” says astronomer CatherineCesarsky ofCEA system accordingly. andrevisedtheirviews the day. Scientists learnedmoreaboutthesolar elementary school.Science appeared to have won you’re fondof,orwhatmnemonicyoulearnedin nated “dwarf planets.” criteria butnot thethird,like Pluto, weredesig- of other bodies. Objectsthatmeet thefirst two For alongtime,Isharedthisview. I’ve been “I believe thatthedecisiontaken was thecorrect Science isnot sentimental.Itdoesn’t carewhat of planetisstill The definition By LisaGrossman a sorepoint 8/11/21 11:47AM

JHU-APL, NASA, SWRI

PLUTO: JHU-APL, NASA, SWRI; TOMBAUGH: GL ARCHIVE/ALAMY STOCK PHOTO gig at the Cornell Daily Sun, when I was a junior Observations from in college in 2006. I interviewed some of my pro- NASA’s mission showed that fessors about the IAU’s decision. One, planetary the surface of Pluto’s scientist Jean-Luc Margot, who is now at UCLA, region is called it “a triumph of science over emotion. Sci- covered in churning nitrogen ice “cells” ence is all about recognizing that earlier ideas may (white polygonal blocks, have been wrong,” he said at the time. “Pluto is top) that constantly Pluto’s Place finally where it belongs.” bring fresh material The definition up to the surface from But another, planetary scientist Jim Bell, now below. Closer views of planet is still at Arizona State University in Tempe, thought the highlight the rugged decision was a travesty. He still does. The idea that water-ice mountains a sore point that border some of planets have to clear their orbits is particularly irk- these cells (bottom). By Lisa Grossman some, he says. The ability to collect or cast out all that debris doesn’t just depend on the body itself. Everything with interesting geology should be a planet, Bell told me recently. “I’m a lumper, not a splitter,” he says. “It doesn’t matter where you are, it matters what you are.” Not everyone agrees with him. “Fifteen years ago we finally got it right,” says planetary scientist Mike Brown of Caltech, who uses the Twitter handle @plutokiller because his research helped knock Pluto out of the planetary pantheon. “Pluto For centuries, the word “planet” was a much had been wrong all along.” more inclusive term. When Galileo turned his But since 2006, we’ve learned that Pluto has an telescope at Jupiter, any largish moving body atmosphere and maybe even clouds. It has moun- in the sky was considered a planet — including tains made of water ice, fields of frozen nitrogen, moons. When astronomers discovered the rocky methane snow–capped peaks, and dunes and vol- bodies we now call in the 1800s, those canoes. “It’s a dynamic, complex world unlike any too were called planets, at least at first. other orbiting the sun,” journalist Christopher Pluto was considered a planet from the very “I have found Crockett wrote in Science News in 2015 when beginning. When , an amateur your Planet X.”

NASA’s New Horizons spacecraft flew by Pluto. astronomer from Kansas newly recruited to the CLYDE TOMBAUGH The New Horizons mission showed that Pluto in Flagstaff, Ariz., spotted it has fascinating and active geology to rival that of in photos taken in January 1930, he rushed to the any rocky world in the inner solar system. And observatory director and declared: “I have found that solidified planetary scientist Philip Metzger’s your Planet X.” view that the IAU definition missed the mark. The discovery was no accident. In 1903, “There was an immediate reaction against the U.S. astronomer hypothesized dumb definition” when it was proposed, says that a hidden planet seven times the mass of Earth Metzger, of the University of Central Florida orbited 45 times farther from the sun. Lowell had in Orlando. Since then, he and colleagues have searched for what he called Planet X until he died been refining their views: “Why do we have this in 1916. The search continued without him. intuition that says that it’s dumb?” The new planet was thought to be “black as coal, nearly as dense as iron, twice as dense as the heavi- Retelling the tale est earthly surface rocks,” Science News Letter, the It turns out that the “we just learned more” predecessor of Science News, reported in 1930. narrative isn’t really true, Metzger says. Though Further research showed Lowell had grossly the official story is that Pluto was reclassified overestimated Pluto’s mass: It’s more like one because new data came in, it’s not that simple. five-hundredth the mass of Earth. Things got even Teaching that narrative is bad for science, and for weirder when scientists realized Pluto wasn’t alone science education, he says. out there. In 1992, an object about a tenth the Clyde Tombaugh, shown The truth is, there’s no single definition of diameter of Pluto was found orbiting the sun “in here with a homemade telescope, discovered a planet — and I’m beginning to believe that’s a the deep freeze of space well beyond the orbits of Pluto in 1930 when he

JHU-APL, NASA, SWRI PHOTO STOCK GL ARCHIVE/ALAMY JHU-APL, NASA, SWRI; TOMBAUGH: PLUTO: good thing. Pluto and ,” as Science News described it. was 24 years old.

www.sciencenews.org | August 28, 2021 21

pluto.indd 21 8/11/21 11:26 AM pluto.indd 22 22 SCIENCE NEWS planets, shrinkingthetotalnumber of planetsinthesolarsystemtoeight. for anewdefinitionofplanetthatredesignated PlutoanditsneighborErisasdwarf On August24,2006,inPrague, members oftheInternationalAstronomicalUnionvoted ESSAY | PLUTO’S PLACE | August 28,2021 reason torejectthedefinition. Metzger, Belland Metzger andcolleaguesthinkthere’s good much just ignoreit.” in publishingpapers,” Metzger says. “We pretty “Planetary scientists don’t usethe IAU’s definition who study Pluto, never bothered to change. but many planetary scientists, especially those of discord. Xena was aptly renamedEris, theGreek goddess was put to a vote. Pluto and Xena got the boot. acrimonious debate,anewdefinition of“planet” the IAU. Onthefinal day, August 24, aftermuch came toaheadin2006atmeeting inPragueof “planet” title,sotoowas Pluto. formation ofthesolarsystem undeservingofthe 10th. But if Xena leftover was anicy from the TV show Xena: Warrior Princess), shouldbethe new discovery, nicknamedXena (inhonorofthe If Plutowas theninthplanet, thensurelythe than Pluto.Belt bodies that seemed tobelarger desire foraformaldefinition of“planet.” objects comingintofocus, therewas agrowing And whatsets themapart?Withsomany new strange newworldswiththemorefamiliarones? questions: Whatcharacteristics couldunitethese Awareness ofPluto’s neighborsbroughtnew ,andtherearemany moreoutthere. been foundhidinginthatfrigidzonedubbedthe In partthatmightbecheek,orspite.But Textbooks were revised, posters were reprinted, Tensions over how Pluto and Xena tocategorize In 2005, Brown spotted thefirst oftheKuiper Since then,morethan2,000 bodieshave icy over time,butnot intheway most peoplethink. public have usedtheword“planet” haschanged researchers show thattheway scientists andthe textbooks andletters datingbackcenturies, the published in 2019 in Icarus make theircaseinapairofrecentpapers, one solar system containshundredsof“planets” — before thediscovery ofthe Kuiper Beltthatthe the NewHorizons missionandhasarguedsince Research Institute, theplanetary scientist wholed others — including AlanSternoftheSouthwest tary sciencewentthrougha“Great Depression” that includedmoonswas forgotten whenplane- fixed sphereofstars. limited numberofplanets moving through the readings, thatinsisted onthesimplicityofa positions ofcelestial bodiesforhoroscope notably astrological almanacsthatused the Surprisingly, it was nonscientific publications, “planets” or “secondary planets” untilthe1920s. argues. had nothing Metzger todowiththe namechange, The factthatasteroids didn’t “cleartheirorbits” different geophysics thanbigger, rounderplanets. adifferentoriginor irregular inshape,suggesting most smallasteroids turnedouttobelumpy and While the largest asteroids still looked planetlike, the term“minorplanets” felloutoffashion. offered better observationsofthese bodies, that as smallacityblockorwidePennsylvania. most are“smallfry.” planets” canbe These“baby of planets areknown tocircleoursun,” although in planets,” well intothe20th century. A 1951 article considered planets, sometimes dubbed “minor colleagues found. and other asteroids were Pluto sufferedthesame fate. neighbors. Inthatsense,thestory goes, Ceresand was stripped of its planetary title thanks to its with hundreds of asteroids piling up, Ceres in the . By the end of the 1800s, after astronomers found the rest of the bodies too. It’s often said that Ceres was demoted was consideredaplanet afterits1801 discovery, asteroid beltbetween MarsandJupiter, Ceres the in as dwarf planetsLocated tobediscovered. Consider Ceres, thefirst ofwhatarenow known In andout After examininghundredsofscientific papers, Metzger thinks thatolderdefinition ofaplanet And what about moons? Scientists called them It wasn’t untilthe1960s, whenspacecraft But that’s not the real story, Metzger and Science News Letterdeclaredthat“thousands and one forthcoming. 8/11/21 11:26AM

MICHAL CIZEK/AFP/GETTY IMAGES

NASA between about 1910 and 1950. So many asteroids had been discovered that searching for new ones Pluto’s orbit or refining their orbits was getting boring. Tele- scopes weren’t good enough to start exploring asteroids’ geology yet. Other parts of space science were way more exciting, so attention went there. But new data that came with space travel brought moons back into the planetary fold. Starting in the 1960s, “planet” reappeared in the scientific literature as a description for satellites, at least the large, round ones.

Real-world usage The planet definition that includes certain moons, asteroids and Kuiper Belt objects has had staying power because it’s useful, Metzger says. Thinking of planets that way leads to big- Crowded space Planetary scientists’ work includes comparing a picture questions about how the solar system put Pluto and hundreds or thousands of other place like Mars (a planet) to (a moon) to itself together. objects that rival Pluto in (a moon that was probably born in the One common argument in favor of the IAU’s size and interest orbit in Kuiper Belt and captured by Neptune long ago) definition is that it keeps the number of planets the icy back of the solar system’s fridge, called to Pluto (a ). It’s scientifically useful manageable. Can you imagine if there were the Kuiper Belt (white to have a word to describe the cosmic bodies hundreds or thousands of planets? How would fuzzy ring). where interesting geophysics, including the the average person keep track of them all? What conditions that enable life, occur, he says. There’s would we print on lunch boxes? I’m not making all sorts of extra complexity, from mountains to fun of this idea; as an astronomy writer who has to oceans and rivers, when rocky been obsessed with space since I was 8, I would be worlds grow big enough for their own to reluctant to turn people off to the planets. make them spherical. But Metzger thinks teaching just eight planets “We’re not claiming that we have the perfect risks turning people off to all the rest of space. definition of a planet and that all scientists ought “Back in the early , there was a lot of to adopt our definition,” he adds. That’s the same excitement when astronomers were discovering mistake the IAU made. “We’re saying this is new planets in our solar system,” he says. “All that something that ought to be debated.” excitement ended in 2006.” But those objects are A more inclusive definition of “planet” would still out there and are still worthy of interest. By also give a more accurate concept of what the solar now, there are at least 150 of these dwarf planets, system is. Emphasizing the eight major planets and most people have no clue, he says. suggests that they dominate the solar system, This is the argument I find most compelling. when in fact the smaller stuff outnumbers those Why do we need to limit the number of planets? worlds tremendously. The major planets don’t Kids can memorize the names and characteristics even stay put in their orbits over long time- of hundreds of dinosaurs, or Pokémon, for that scales. The gas giants have shuffled around in the matter. Why not encourage that for planets? Why past. Teaching the view of the solar system that not inspire students to rediscover and explore includes just eight static planets doesn’t do that the space objects that most appeal to them? dynamism justice. I’ve come to think that what makes a planet Caltech’s Brown disagrees. Having the may just be in the eye of the beholders. I may be a gravitational oomph to nudge other bodies in lumper, not a splitter, too. s and out of line is an important feature of a world, he says. Plus, the eight planets clearly dominate Explore more our solar system, he says. “If you dropped me in s Philip T. Metzger et al. “The reclassification of the solar system for the first time, and I looked asteroids from planets to non-planets.” Icarus. around and saw what was there, nobody would February 2019. say anything other than, ‘Wow, there are these s Philip T. Metzger et al. “Moons are planets: eight — choose your word — and a lot of other little Scientific reductionism vs. cultural teleology in

MICHAL CIZEK/AFP/GETTY IMAGES MICHAL CIZEK/AFP/GETTY NASA things.’ ” the taxonomy of planetary science.” In prep.

www.sciencenews.org | August 28, 2021 23

pluto.indd 23 8/11/21 11:26 AM FEATURE

The Debate Over Gender-Affirming Health Care Researchers explore the benefits and risks for transgender youth By Maria Temming

aniel’s birth certificate is marked they say they’re happier with life. “I definitely feel “female,” but Daniel is nonbinary — more like myself. Like I was just existing before, not exclusively male nor female. “I’m but now I’m living, now that I’m open to everyone Dmasculine leaning,” says the 18-year-old. about who I am, and most importantly I’m open The disconnect between Daniel’s gender iden- to myself,” says Daniel, whose last name is being tity and physical appearance, which was apparent withheld for medical privacy. “Starting testoster- to them around age 4, became unbearable during one, for me, saved my life.” puberty. “I hated showers because I didn’t like Daniel’s hormone therapy is just one method looking at my body,” Daniel says. “I just felt really that doctors use to bring a person’s body into uncomfortable with the idea of being female.” alignment with their gender identity, an approach At 13, Daniel came out to their mother as trans- known as gender-affirming health care. This kind gender, someone whose gender identity does not of care looks different for people of different ages. match the sex they were assigned at birth. For young children, it is limited to allowing them About a month after coming out, Daniel to socially express their gender, with perhaps a started seeing a therapist who specialized in name and pronoun change. Adolescents may take gender identity. A year later they were referred medications to delay puberty, followed by gender- to an endocrinologist, who prescribed the sex affirming hormones and possibly surgery. While Proposed restrictions on hormone testosterone. For Daniel, the most researchers are still investigating potential risks, gender-affirming health care are part of a recent important effect was a deeper voice. “My biggest existing evidence suggests that these treatments wave of legislation problem with getting misgendered was that my could have life-saving mental health benefits. that some LGBTQ voice was really high,” Daniel says. Over the last 20 years or so, gender-affirming advocates say unjustly discriminates against Before starting hormone therapy, Daniel con- treatment has become the standard of care for

transgender people. sidered suicide. With masculinizing hormones, transgender people in the United States. That IMAGES DREW ANGERER/GETTY C. CHANG

24 SCIENCE NEWS | August 28, 2021

transgender.indd 24 8/11/21 11:49 AM DREW ANGERER/GETTY IMAGES transgender.indd 25

C. CHANG supporting achildthrough socialtransition. cal treatments. Itentails parentsanddoctors gender-affirming healthcareinvolves nomedi- For childrenwhohaven’t yet started puberty, Transitioning inchildhood the mentalhealthoftransgender youth.” gender-­ Medicine. “All existing researchsuggests that try researcheratStanfordUniversity Schoolof Jack Turban,achildandadolescentpsychia- those alarmingstatistics groups, acrossage says had attempted it. ered suicideinthepreviousyear, and21percent a nationalsurvey in2020, 52percenthadconsid- andnonbinaryyouthwhoparticipatedin gender anxiety (SNOnline:3/1/17). Among13,600 trans- as likely astheirpeerstohave depressionor depression andself-harm. apopulationalreadyatsevere riskofendanger affirming care,arguingthattherestrictions would Endocrine Society have endorsed gender the American Academy of Pediatrics and the include impactsonfertilityandbonehealth.But later regret, as well asmedical risks, which may dren fromlife-alteringprocedurestheymay transgender youthsay theywant toprotect chil- just by theideasbeingputoutby thesebills.” tobehurtacross thiscountryarealreadygoing HealthLangone inNewYork City. “Many people Jason Klein,apediatricendocrinologist atNYU isbeingdone,”in committee, thedamage says toll onmany transgender youth,expertssay. law inJuly failed other states. Althoughseveral ofthoseproposals ilar billshave beenproposedinmorethanadozen ban gender-affirming treatments for minors. Sim want it.InApril,Arkansas becamethefirst state to to gender-affirming healthcareforthosewho swell of state legislation has sought to curb access effects ofgender-affirming care,arecentground- Europe thatshow thepositive mentalhealth U.S. CentersforDiseaseControlandPrevention. high schoolersaretransgender, accordingtothe a mentaldisorder. About 1.8percentofAmerican is anormal exampleofhuman diversity andnot the medicalcommunitythatbeingtransgender has followedchange increasing recognition in Gender-affirming healthcarecouldimprove Transgender youtharethreetofourtimes Proponents ofhealthcarerestrictions for “Even ifthebillsdon’t pass, even iftheydie Despite findings fromtheUnitedStatesand — affirming medicalinterventions improve and a federal judge blocked theArkansasand afederaljudge — they may still exactamentalhealth ­- -

gender-affirming treatment options may allow University Medical Centers. Thus, nonpermanent and adolescentpsychiatrist attheAmsterdam much aboutit,” says Annelou deVries, achild identityevolves gender withage. the results. Researchersarestill investigating how outdated andoverly broadcriteria,thusskewing may have beenconsideredtransgender basedon that thosestudies includedmany childrenwho when theygrow up. Butothers have pointedout der inearlychildhoodwillnot continuetodoso 80 percent of people who identify as transgen have citedstudies suggesting thatasmany as torically shown highlevels ofdepression. socially transitioned,ontheother hand,have his- Psychiatry. Transgender kidswhohave not the AmericanAcademyofChild&Adolescent researchers reported in 2017 in the transgender, or cisgender, siblings and peers, Canada wereaboutthesame asfortheirnon­ der childrenfromacrosstheUnitedStatesand more than100sociallytransitionedtransgen- Levels ofdepressionandself-worth reportedby appears toboost youngpeople’s mentalhealth. some timetokindofadjust.” exactly whothey are, and the parents might need that —thekidsarevery solidandsteady andknow selves,” Klein says. “Sometimes, the parents need forthem- identityandtheirgoals their gender need moreconversation andtimetothinkabout ilies throughthisprocess. “Sometimes, thekids however feelsmost authentictothem. and allowing thechildtodressorweartheirhair identityusing the pronouns that fit their gender This may mean calling thechild by anew name, Number ofanti-transgender billsintroducedinstatelegislatures,2015–2021 2021 2020 2019 2018 2017 2016 2015 “We have tobehonest. We don’t know so Opponents ofgender-affirming healthcare Being supportedthroughasocialtransition Mental health care professionals can help fam- 12 16 20 25 25 28 4 3 3 2 4 24 17 30 87 17 www.sciencenews.org Journal of - Other

transgender medicalcare Bans/restrictions on and youth sportsbans Bathroom/locker-room bans CAMPAIGN, ASOFJULY 27,2021 SOURCE: HUMANRIGHTS care forminors. gender-affirming health restrict accessto identities. Otherbills match theirgender on sportsteamsthat bathrooms orcompeting people fromusing seeks tobartransgender U.S. statelegislation A recentsurgein Limiting laws had consideredsuicide surveyed in2020who Proportion whohad in theprevious year attempted suicide nonbinary youth | transgender and 21 52 August28,2021 Proportion of percent percent 35

25 8/11/21 11:49AM 9 FEATURE | THE DEBATE OVER GENDER-AFFIRMING HEALTH CARE

Differences in mental health among Dutch adolescents puberty blockers while growing up, but just Transgender adolescents who Transgender Cisgender 2.5 percent of them received the medications. had not started treatment adolescents taking adolescents Youth who visited a gender identity clinic but puberty blockers hadn’t started treatment had more emotional prob- 35 lems such as anxiety and depression, and suicidal 30 tendencies than their cisgender peers, a study of 25 1,100 youth in the Netherlands found. In contrast, 20 children receiving puberty blockers at that clinic 15 showed similar or better psychological function-

Percentage 10 ing than cisgender kids, the researchers reported 5 in 2020 in the Journal of Adolescent Health. 0 Daniel wishes they’d had the opportunity to take Had clinical-range scores for Expressed suicidal thoughts the medications. “I really do believe if I’d been on emotional problems [puberty] blockers, things would have been a lot Closer to OK children time to safely explore their identity as easier for me,” Daniel says. “I would have still Emotional problems, they approach adolescence, proponents say. struggled, but it would have been easier to handle.” such as depression or anxiety, that would One possible side effect of puberty blockers qualify for mental health Pausing puberty is delayed bone development. The medications care were much more At the start of puberty, children who are trans- interrupt the rapid buildup in bone density that common among trans- gender teens who had gender or questioning their gender identity may generally occurs during puberty, potentially lead- not been treated with begin taking medications that suppress the natural ing to weaker bones in adulthood. But long-term puberty blockers than release of estrogen and testosterone, sex hormones data from people treated for precocious puberty among those who had received those medica- that cause the body to change. Such puberty block- suggest that bone development catches up once tions, in a study of Dutch ers can be taken through an injection once a month people stop taking puberty blockers. youth. Similarly, a higher or every few months, or through a small implant Likewise, early data on transgender youth indi- percentage of trans- gender teens who had inserted in the upper arm and replaced annually. cate that hormone therapy helps bone growth catch not received puberty “These medications are fully reversible,” says up once teens stop taking puberty blockers, de Vries blockers expressed Russell Toomey, a family studies and human says. Long-term data don’t yet exist to comprehen- suicidal thoughts than trans peers who had re- development researcher at the University of sively assess the impacts in transgender adults. ceived the medications Arizona in Tucson. When someone stops taking To be safe, Johanna Olson-Kennedy, who and than cisgender, or them, the body picks up where it left off and pro- practices pediatrics and adolescent medicine at nontransgender, teens. SOURCE: A.I.R. VAN DER ceeds through puberty. Children’s Hospital Los Angeles, gives special MIESEN ET AL/J. ADOLESCENT Delaying puberty allows transgender children instructions to her patients starting puberty HEALTH 2020 to go through their early teenage years with- blockers. “We have them take vitamin D and out experiencing potentially distressing body calcium supplementation, and we stress the changes not aligned with their gender identity, importance of weight-bearing exercise, which is Toomey says. For adolescents who later receive critical for shoring up bone density.” hormones, puberty blockers can limit the devel- opment of physical features such as breasts that Reversible and not would require surgery to change later. Older transgender adolescents can start taking Puberty blockers are among the gender-­ gender-affirming hormones, as Daniel did. A new affirming treatments forbidden by the latest law in Tennessee bans such hormones for prepu- bills. But these medications are not new and are bescent children. Yet current medical guidelines not just for transgender youth. They have been do not recommend hormone therapy earlier than used for decades to treat children who start show- about age 14 to 16. ing signs of puberty before age 8 or 9, a condition Masculinizing hormone therapy involves taking known as precocious puberty. For transgender testosterone to promote changes like voice deepen- youth, these time-tested medications can be a ing and facial hair growth, while suppressing men- lifeline. Transgender adolescents who had access struation and breast development. Daniel takes to puberty blockers were 70 percent less likely testosterone through injections, but the hormone to consider suicide than those who could not get can also be absorbed via skin ointment or a patch. the medications, according to a 2020 study in Feminizing hormone therapy involves taking Pediatrics. Of the more than 20,000 U.S. transgen- estrogen through a pill, patch or injection, often

der adults surveyed, nearly 17 percent had wanted with a separate drug to block the body’s natural C. CHANG IMAGES MEDIA/GETTY BARCROFT

26 SCIENCE NEWS | August 28, 2021

transgender.indd 26 8/11/21 12:48 PM C. CHANG transgender.indd 27

BARCROFT MEDIA/GETTY IMAGES gender-associated diseases.gender-associated For example,trans may have ahigher-than-before riskofcommon Health. ers reportedin2017 inthe Journal ofAdolescent preservation options, just twousedthem,research- 72 transgender adolescentscounseled on fertility research echoesthatobservation.At oneclinic,of straints [or]timeconstraints,” Kleinsays. Recent because of financial constraints, insurance con- that’s becauseoftheirown wants orneeds, or sue fertility preservation techniques or sperm. uninterrupted pubertytoproduceviableeggs be lesslikely through thanthosewhohave gone adolescents whohave taken pubertyblockers may hormones —although gender-affirming starting their fertilitycanfreeze eggsorbankspermbefore person toperson.People whowant topreserve can both affect fertility, but the effects varyfrom but it’s not risk-free. Testosterone andestrogen studies areincrediblycompelling.” those that transyouthfaceforsuicideingeneral, we consider the incredibly heightened risk “When University Feinberg SchoolofMedicine inChicago. minorityhealthresearcheratNorthwestern gender efforts continue,says LaurenBeach,asexualand treatments have apositive impact,even asresearch care aresmall, taken together they suggest the mental health effects of gender-affirming health before treatmenttoabout51afterward. ratings fell 20 points on average, from about 71 dissatisfaction), teens’self-reported 116 (highest On abodydissatisfaction scalefrom0(none)to before, researchersreportedin2020Pediatrics. about one year of treatment than they were surveyed werehappierwiththeirbodiesafter that 86transgender teens onhormone therapy Psychology. Another study ataTexas clinicfound reported in2019 inClinicalPractice in Pediatric apy, whilesix did aftertreatment,researchers suicidal tendenciesbeforestarting hormonether study ataMissourichildren’s hospitalexpressed if treatmentstops. in musclemassandfatdistribution arereversible development, arepermanent,whereaschanges facial hairgrowth, voice deepeningandbreast mass. Someeffectsofhormonetherapy, suchas slows body hair growth and decreases muscle testosterone. Thiscausesbreast development, Transgender individuals taking hormones “In my experience, most people do not pur Hormone therapy consideredsafe, isgenerally While studies like theseandmany others onthe Twenty-one outof47transgender youthina —

whether - -

Plastic andReconstructive Surgery in2019. itive impactontheir lives inasurvey publishedin reported theprocedurehadanoverallsurgery pos- of 58individualswhohadmasculinizingchest tal healthandqualityoflifeformany. Allbutone hasbeenshown toimprovecare, surgery men- cians,” Turbansays. coordination between afamilyandtheirphysi- “This is amajor decision that requires careful comfort from unwanted breast development. if they experience severe distresssurgery or dis- some adolescentsmay have masculinizingchest forminors, surgery not but recommendgenital people. Current medical guidelines dogender treatment caninvolve forsome trans- surgery Safer says, butexisting datacannot say forsure. other men,have ahigherriskofhighcholesterol, Transgender mentakingtestosterone may, like from taking estrogen-containing birth control. cisgender women’s risk of developing blood clots risk ofdeveloping bloodclots, butnot higherthan Trans womenwhotake alsohave estrogen aslight inNewYork Medicine andSurgery gender City. who directstheMount SinaiCenterforTrans- higher riskthanother women,says Joshua Safer, of breast cancerthancisgender men,butnot women whotake estrogen may beathigherrisk from both adolescentsandtheirparents forany health careproviders children andtheirparents, physicians andmental surgery, involves extensive conversations among affirmation, from social transition toof gender Medical guidelinesrecommendthatevery stage Risk ofregret Like other aspectsofgender-affirming health Beyond hormonetherapy, gender-affirming — and informedconsent www.sciencenews.org

since age2. she’s knownsheisagirl 8 inthis2009photo,says Kyla Lechelt ofIdaho,age labeled aboy atbirth, identities. Though express theirgender helps transgender youth Gender-affirming care therapies Effects ofhormone identity. align withtheirgender body changesthat estrogen topromote feminizing hormone testosterone orthe masculinizing hormone old may starttakingthe about 14to16years Transgender teens Body changes growth Decreased bodyhair Breast growth Skin softening Body fatredistribution mass Decreased muscle Estrogen growth Facial andbodyhair Increased musclemass Voice deepening Body fatredistribution menstruation Suppressed Testosterone | August28,2021 27 8/11/21 11:50AM FEATURE | THE DEBATE OVER GENDER-AFFIRMING HEALTH CARE

Right timing For medical procedures. “It’s not that you decide on gender-affirming health care as experimental or young children, gender- your 12th birthday where you are when you’re 21,” dangerous may make people who are questioning affirming health care is de Vries says. their gender reluctant to ask for help, Klein says. limited to providing sup- port through a change Some lawmakers who have pushed bills to ban The bills may also make parents reluctant to seek in name and pronouns puberty blockers and hormone therapy for minors help for their children even in places where treat- and clothing style, but have argued that children who receive gender- ment has not been made illegal. no medication. Older adolescents may receive affirming treatment may regret it when they grow These health care bills are just one aspect of medical treatments, up. Regret is a risk. But current research says that a wave of legislation that some LGBTQ advo- including puberty block- regret following gender-affirming medical and cates say discriminates against the transgender ers, hormone therapy or surgery, if appropriate. surgical care is rare, Turban says. community. A new law passed in Tennessee, but One team tracked the development of 55 trans- temporarily halted by a federal judge, requires When health care support is considered gender adults in the Netherlands who received businesses and government facilities to post signs puberty blockers and gender-affirming hor- if they allow transgender people to use bathrooms Age (years) Options mones in adolescence, followed by that match their gender identity. <8 Social transition-­related surgery in early And several states, including Florida, transition adulthood. After surgery, partici- Mississippi and Tennessee, now for- pants had similar quality of life and bid transgender kids from playing on 8–14 Puberty 61 blockers happiness as their cisgender peers. percent sports teams that match their gen- All were satisfied with their appear- Fraction of transgender der identity. In late July, a federal >14 Hormone ance and none regretted treatment, and nonbinary youth who judge prevented West Virginia from therapy according to a 2014 report in reported being prevented enforcing its sports ban. or discouraged from using 18 (with Surgery Pediatrics. A recent review of more a bathroom corresponding “We know that a major driver exceptions) than two dozen studies that include with their gender identity of mental health problems among nearly 8,000 transgender patients transgender youth is rejection of who had gender-affirming surgeries similarly their gender identity,” Turban says. “Imagine showed that only about 1 percent regretted treat- that you heard powerful politicians pronouncing ment, researchers reported in March in Plastic on the national stage that you’re confused, invalid and Reconstructive Surgery-Global Open. and dangerous to people in bathrooms and sports A small percentage of people do choose to leagues. It’s extraordinarily difficult for a child not discontinue therapy. Among more than 800 ado- to be negatively impacted by this rhetoric.” lescents who visited a gender identity clinic in Research is just emerging on how recent anti- the Netherlands over a 40-year period from 1972 trans legislation may affect transgender youth and to 2015, 1.9 percent of those who started taking their families. Parents of transgender children puberty blockers did not proceed with hormone expressed anxiety about the increased stigma therapy, researchers reported in 2018 in the their kids may face, and the potential health Journal of Sexual Medicine. And some adults who impacts of lack of access to gender-affirming care, undergo gender-affirming treatments later decide according to a small online survey published on to return to living as the gender assigned to them July 29 in Psychology of Sexual Orientation and at birth, a process called detransitioning. Gender Diversity. “I am afraid for those kids who In a survey of nearly 28,000 transgender adults might find death preferable to being forced to go in the United States, about 2,200 had detran- through the bodily changes of puberty for the sitioned. About 36 percent cited pressure from wrong gender,” says a Texas mother quoted in parents as a reason. Close to 33 percent reported the study. pressure from community and 27 percent said they Daniel can relate. “It’s frustrating. It angers had trouble getting a job. Just under 11 percent me,” they say. “But it’s also so confusing, because said that fluctuations in their gender factored into what is the point of stopping people from being their detransition, Turban and colleagues report who they are, and doing things that could possibly in the June LGBT Health. save their life?” s

Legal ramifications Explore more Legislation aiming to restrict gender-affirming s Caroline Salas-Humara et al. “Gender affirming health care may have more widespread conse- medical care of transgender youth.” Current quences than preventing minors in some states Problems in Pediatric and Adolescent Health Care. from receiving treatment. Bills that portray September 2019.

28 SCIENCE NEWS | August 28, 2021

transgender.indd 28 8/11/21 11:50 AM The Perfect Environment to Make a Big Impact

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_p29.indd 29 8/4/21 2:10 PM REVIEWS & PREVIEWS

BOOKSHELF The problem is, “real” science also sometimes suffers from The real meaning of errors of rigor and logic, as recent concerns about reproduc- ing experimental results have demonstrated (SN: 3/27/10, pseudoscience p. 26). So drawing a sharp line between real and pseudo There is no such thing as pseudoscience, remains a difficult task. and Michael Gordin has written a book Gordin provides neat, quick summaries of all these issues about it. in his brief but thoughtful and enjoyable book. Most valuable In On the Fringe, Gordin, a historian at of all is his first chapter, in which he demolishes the notion Princeton University, does not deny that that philosopher Karl Popper ’s “falsifiability” criterion On the Fringe there are endeavors afoot in the world allows a clear demarcation between science and non- (or Michael D. Gordin that are labeled pseudoscience. Rather pseudo-) science. Falsifiable, Gordin points out, is undefin- OXFORD UNIV., $18.95 he shows that the term has no precise able. If nothing else, every working scientist (and science meaning, and that there is no unambiguous, universal test for journalist) should read this chapter to learn that the refrain delineating true science from the false versions on its fringe. “if it’s not falsifiable, it’s not science” is philosophically Many well-known examples of pseudoscience, he notes, unsound gibberish, a sign of a weak argument. were once mainstream scientific disciplines. , for Still, some pseudoscience is clearly out of bounds. And some instance, was for centuries respected or practiced by the would say the scientific revolution of the 17th century estab- most prominent scientific thinkers of their time. lished new rules that filtered bad science from the good. But it Astrology’s time is long past, of course. So Gordin refers still took a while for modern science to do away with astrol- to it, and alchemy, and eugenics, as vestigial sciences — once ogy and alchemy. Later, eugenics and even ESP were for a regarded as totally scientific, but cast aside into the pseudo- time taken seriously by some “modern” scientists. Some- science realm by the advance of knowledge. times it just takes time to identify bad science and discard it. Other pseudosciences arise having never attained As Gordin writes, science is not a “fixed repository of respectable scientific status. Some are ideologically driven information,” but a dynamic enterprise focused to a large “hyperpoliticized” sciences; some, like creationism, are extent on “refuting or revising past knowledge.” So in a sense “counterestablishment” ventures that feign scientific the scientific revolution did not really render the science of trappings; others are wishful thinking delusions like extra- the ancient Greeks or Middle Ages pseudoscience, but rather sensory perception. just revealed it to be primitive science, awaiting better meth- Advocates for many such pseudosciences seek legitimacy ods, technologies and insights. As science historian Steven by imitating the scientific process — holding conferences, Shapin opened his 1996 book on that topic, “There was no publishing journals and claiming to cite evidence (though such thing as the Scientific Revolution, and this is a book presented in ways riddled with logical fallacies). about it.” — Tom Siegfried

BOOKSHELF far more than just two scientists, Two physicists star in the Big Bang’s origin story Halpern would be hard-pressed to pick two better mascots. George Gamow The Big Bang wasn’t always a sure bet. In Flashes of Creation, physicist Paul was an aficionado of puns and pranks For several decades in the 20th century, Halpern recounts Gamow’s and Hoyle’s and had a keen sense of how to explain researchers wrestled with interpreting interwoven stories. The book bills itself science with charm and whimsy. The cosmic origins, or if there even was a as a “joint biography,” but that is a dis- fiercely stubborn Fred Hoyle had a beginning at all . At the forefront of that service. While Gamow and Hoyle are the darker, more cynical wit, with an artis- debate stood physicists George central characters, the book is tic side that showed through in science Gamow and Fred Hoyle : One a meticulously researched his- fiction novels and even the libretto advocated for an expanding tory of the Big Bang as an idea: of an opera. Both wrote popular sci- universe that sprouted from a from theoretical predictions ence books — Gamow’s Mr Tompkins hot, dense state; the other for in the 1920s, to the discovery series, which explores modern physics a cosmos that is eternal and of its microwave afterglow in through the titular character’s dreams, unchanging. Both pioneered 1964, and beyond to the real- are a milestone of the genre — and took contemporary cosmology, ization in the late 1990s that to the airwaves to broadcast the latest laid the groundwork for our the expansion of the universe scientific thinking into people’s homes. understanding of where atoms is accelerating . “Gamow and Hoyle were adventurous Flashes of Creation come from and brought Paul Halpern Although the development loners who cared far more about cosmic science to the masses. BASIC BOOKS, $30 of cosmology was the work of mysteries than social conventions,”

30 SCIENCE NEWS | August 28, 2021

reviews.indd 30 8/11/21 11:51 AM Halpern writes. “Each, in his own way, As far as the elements go, both were beings. Gamow’s devil-may-care was a polymath, a rebel, and a master of right. “One wrote the beginning of the attitude wore on his colleagues, and his science communication.” story of element creation,” Halpern excessive drinking took its toll. Hoyle, While the Big Bang is now writes, “and the other wrote the end- in his waning decades, embraced entrenched in the modern zeitgeist, ing.” We now know that and outlandish ideas, suggesting that epi- it wasn’t always so. The idea can be helium nuclei emerged in overwhelm- demics come from space and that a traced to Georges Lemaître, a physicist ing abundance during the first few dinosaur fossil had been tampered with and priest who proposed in 1927 that minutes following the Big Bang. Stars to show an evolutionary link to birds. the universe is expanding. A few years took care of the rest. And he went to his grave in 2001 still later, he suggested that perhaps the Halpern treats Gamow and Hoyle railing against the Big Bang. cosmos began with all of its matter in a with reverence and compassion. Re- Capturing the history of the Big Bang single point — the “primeval atom,” he created scenes provide insight into how theory is no easy task, but Halpern called it. In the 1940s, Gamow latched both approached science and life. We pulls it off. The biggest mark against on to the idea as way to explain how all learn how Gamow, ever the scientist, the book, in fact, may be its scope. To the atomic elements came to be, forged roped in physicist Niels Bohr to test pull in all the other characters and side in the “fireball” that would have filled ideas about why movie heroes always plots that drove 20th century cosmol- the cosmos in its earliest moments. drew their gun faster than villains — a ogy, Gamow and Hoyle sometimes get Hoyle balked at the notion of a moment test that involved staging a mock attack forgotten about for long stretches. A bit of creation, convinced that the uni- with toy pistols. We sit in with Hoyle more editing could have sharpened the verse has always existed — and always and colleagues while they discuss a book’s focus. will exist — in pretty much the same horror film, Dead of Night, whose cir- But to anyone interested in how the state we find it today. He even coined cular timeline inspired their ideas idea of the Big Bang grew — or how any the term “Big Bang” as a put-down about an eternal universe. scientific paradigm changes — Flashes during a 1949 BBC radio broadcast. And Halpern doesn’t shy away from of Creation is a treat and a worthy trib- The elements, Hoyle argued, were darker moments, inviting readers to ute to two scientific mavericks. forged in stars. know these scientists as flawed human — Christopher Crockett

www.sciencenews.org | August 28, 2021 31

reviews.indd 31 8/11/21 11:51 AM SOCIETY UPDATE

CONVERSATIONS WITH

MAYA RODERIC PETTIGREW CEO of Engineering Health & Executive Dean for Engineering Medicine at Texas A&M University

Maya Ajmera, President & CEO of the Society for Science and Publisher of Science News, chatted with Roderic Pettigrew, an alumnus of the 1967 International Science and Engineering Fair (ISEF). Pettigrew, who won the Vannevar Bush Award from the National Science Foundation and was the founding director of the National Institute of Biomedical Imaging and Bioengineering (NIBIB), currently serves as CEO of Engineering Health and Executive Dean for Engineering Medicine at Texas A&M University, in partnership with Houston Methodist Hospital. We are thrilled to share an edited summary of their conversation.

How did competing in ISEF in 1967 impact your life and I won’t forget it. His telegram said, “Pettigrew, takes fourth! are there moments that still stand out to you? Pettigrew takes fourth!” Given all of the obstacles we had to Going to ISEF was quite a memorable experience. Growing overcome, it was as if I had won a gold medal. up in the segregated South in the ’60s, this stands out as a signiicant event in my history. I appreciated it at the time, Your undergraduate education was in nuclear science and I appreciate it even more in retrospect. and engineering. How did you ind your way to the Even though I was born during the era of Jim Crow and biological sciences? racial segregation, I was fortunate in two ways. One, my I always had this basic interest in the welfare of man and a immediate family was solid. My parents were people of love of science. Those two come together in the biological impeccable character. They valued the dignity of others. They sciences and medicine. When I was a graduate student at taught us to always consider the well-being of others. Second, MIT, I had no medical school plans, but I did plan to work on as a young person, I was always interested in science. I often problems that would improve people’s lives. describe myself as having come out of the womb a scientist. While conducting my Ph.D. research, I spent a lot of In 10th grade in Albany, Georgia, I had a highly impactful time at Massachusetts General Hospital. Being in that teacher, Robert Roquemore, who taught us that being a environment was eye-opening. I began to think that not only scientist means you are able to understand the laws of nature did I want to work as a physical scientist, but I felt I could and the basic principles that govern how things work. Those be more eff ective if I really understood those problems principles can lead you to discovery. irsthand, which is what led me to medical school. At ISEF in San Francisco, Mr. Roquemore was so thrilled when my name was called as a fourth-place prize winner. I You were the founding director of NIBIB. What was your was just delighted to be participating. I recall that during experience in building the institute from the ground up? the award ceremony, Mr. Roquemore was behind me and It was a marvelous experience to be named the founding had to kick me under my seat when my name was called director. I consider myself to be very privileged and a classic because my reaction was delayed. He was just ecstatic. He example of having the right blend of talents, experience and sent a telegram back to Monroe High School in Albany, and interest at the right time.

SN_015_21_C.indd 32 8/11/21 12:12 PM The experience was uniquely challenging because although as ethnicity, cultural variations, diff erential life experiences Congress was responsive to the call to establish this new and perspectives. institute, the National Institutes of Health (NIH) itself, including It’s been encouraging to see people from diff erent walks NIH leadership, was not happy about the new institute of life come together and demand changes to eradicate and didn’t see the need for it. From a practical standpoint, systemic racism. Many sectors are starting to realize that adding another institute meant that whatever funding the humanity does indeed bind us, and the lost opportunity and new institute received would not be available to the existing self-injury our entire society will continue to endure if social institutes. So for that reason, there was some resistance and injustice is not addressed. hurdles that we had to overcome. In addition, there was a need to harmoniously blend the professional engineering and Recruiting students of color into STEM ields has long medical communities that had not operationally converged. been a challenge. As a dean, how are you expanding access? The value of this, however, was inexorable. Diverse teams are more eff ective at problem-solving. There is a national need to recruit more diverse students in order to What was your biggest medical accomplishment as part properly respond to the growing challenges facing society. of the institute? Having a diverse faculty base certainly helps when recruiting The institute became the home for what is now referred to as students, but expanding access to STEM starts long before convergence research. It became the home for the integration they reach higher education, and this merits sustained of the physical sciences, life sciences and engineering. The attention as undergraduates. power of convergence is indisputable and is in great evidence Black students, like all students, need to be recognized now. We even see it in this pandemic. It’s through convergence and valued for their potential and the critical role they play that we arrived at these vaccines at unprecedented speed and in enhancing the eff ectiveness of the scientiic enterprise the multiple widely available tests. through diversity. These students should be nurtured and The technologies that emerged from NIBIB have been mentored throughout the pipeline. Key elements include in development for some time, but they involve genetic su icient numbers to provide a supportive community, a engineering, they involve immune engineering, they involve culture that welcomes and provides a sense of belonging, bringing together the physical sciences and the life sciences. mentors that off er guidance, sustained assistance and a plan That’s really what I’m proud of. Realizing this convergence for addressing inancial impediments. and its impact — both now and in the future. There are so many challenges in the world today. You have spoken about the Black Lives Matter movement. What keeps you up at night? What are your thoughts about its impact? As someone who is driven by problem-solving, it is hard to My comments following the Central Park peaceful bird watcher sleep at all amidst so many challenges plaguing society. A incident and the George Floyd killing were about the need more recent challenge that’s been at the top of my mind is for everyone to recognize that humanity binds us all. In so the racial and societal inequity in health care illuminated by doing, I sought to also illuminate the clear systemic nature COVID-19. This has been even more greatly compounded of racism as a real social phenomenon with which we still by inequities in vaccinations, consequent to both an wrestle. I have experienced this all of my life despite eff orts understandable history-based hesitancy among minorities to make meaningful contributions to society and interact and systemic inequities in access and communication. with people as people. Data from the U.S. Centers for Disease Control and Prevention Ultimately, it was a call to understand the commonality shows that minorities are inoculated at levels far below we share. It was also a call to appreciate the inherent value their share of the population. Black, brown and Indigenous that experiential, racial and ethnic diff erences bring to the Americans constitute a population that is more likely to suff er composite human community. It was a call to appreciate our more severe consequences. This is an illustration of a broader common core as humans, to be humane and to embrace the problem in our society in which those with the greater need are lavor that comes from noncharacter-based diff erences, such often those who don’t beneit from modern medicine. I think the convergence of the sciences and engineering can accelerate the development of purposeful technologies to institute functional guardrails and ease of practical implementation into our health care delivery system. I also think we can engineer technological innovations to help overcome the social divide that works against health equity and more broadly address the composite social determinants Pettigrew is joined by his classmates at MIT. He received his Ph.D. in radiation physics at MIT in 1977. of health. There is this opportunity, which science, inclusive of social science, can help answer.

SN_015_21_C.indd 33 8/11/21 12:13 PM FEEDBACK

Neuroscience mysteries Bound by biology A three-dimensional look at 50,000 brain HIV’s ability to create myriad variants in a cells taken from a woman with epilepsy single person partly explains why scientists uncovered some pairs with an astonish- haven’t been able to fi nd an effective vac- ingly large number of c onnections, Laura cine, Erin Garcia de Jesús reported in “Why Sanders reported in “An intricate brain HIV vaccines remain elusive” (SN: 7/3/21 & map reveals quirks,” (SN: 7/3/21 & 7/17/21, p. 14). 7/17/21, p. 6). Given this high rate of mutation, reader Given that nerve cells usually touch Art Hager wanted to know why HIV once, reader Leilani wondered if the hasn’t found ways to spread through woman’s epilepsy could be the reason the air or through mosquitoes. for the cells’ multiple connections. Even HIV has its limits, Garcia de The researchers don’t think epilepsy Jesús says. The virus doesn’t last long is responsible for this cellular quirk, outside the body, and the changes it Sanders says, but for now, we can’t be would have to undergo to spread in JULY 3, 2021 & JULY 17, 2021 sure. “The tissue that scientists used to alternative ways would likely be more reconstruct the map was thought to be trouble than they’re worth, she says. SOCIAL MEDIA healthy, normal tissue that was removed “Let’s pretend that HIV is a small animal See the forest for to allow access to the spot in the wom- living on a mountain. This animal wants the trees an’s brain where seizures started. But to get from peak A to peak B, but the val- it’s possible that abnormal neural activ- ley in between is fi lled with wolves. The Conserving big, old trees such ity infl uenced the cells in that suppos- creature looks to peak C, but that valley as baobabs (one shown below) edly healthy tissue too,” she says. “Until has a lake that is impossible to cross. So in Madagascar, can slow the scientists have more maps that are it might as well stay on peak A where devastation of climate change, made from a wider variety of brains, we there’s plenty of food and space, even if Susan Milius reported in won’t know how common any of these there are a few hawks fl ying around.” “First, protect today’s forests” ‘rare’ fi ndings actually are.” (SN: 7/3/21 & 7/17/21, p. 24). What gives, eggsactly? The story reminded reader Frankly, my deer, I don’t give a slam An experiment on the International Space @StephenChuaEOS of the Gray wolves in Wisconsin that use roads Station suggests that space radiation beloved children’s book as travel corridors may scare deer away, doesn’t affect the viability of sperm, Maria The Little Prince. On reducing deer-vehicle collisions, Jack J. Lee Temming reported in “After spending years Twitter, he shared the reported in “Gray wolves clear deer from in space, mouse sperm produce healthy little prince’s sim- roadways” (SN: 7/3/21 & 7/17/21, p. 8). pups” (SN: 7/3/21 & 7/17/21, p. 16). ple philosophy: Reader John Hosack asked if this wolf Reader Suzan Chastain wondered “It’s a question behavior leads to increased wolf-vehicle whether eggs are similarly unaffected of discipline.… When you’ve collisions. by space radiation. fi nished washing and dressing Wolf-vehicle collisions occur, Lee More research is needed to under- each morning, you must tend says, but less frequently than deer- stand how eggs fare in space, says your planet.” vehicle collisions do. According to the biologist Teruhiko Wakayama of Wisconsin Gray Wolf Monitoring the University of Yamanashi in Kōfu, Report, there were 21 wolf-vehicle col- Japan. Long-term experiments with lisions in the state from April 2019 to mouse eggs are challenging because, April 2020. That number is much lower unlike freeze-dried sperm, the eggs than the nearly 20,000 deer-vehicle col- must be stored at temperatures of Join the conversation lisions that occur in the state each year. about –196° Celsius and the freezers E-MAIL [email protected] Gray wolves’ small population size likely on the International MAIL Attn: Feedback 1719 N St., NW contributes to the low numbers, Lee don’t get that cold, Wakayama says. Washington, DC 20036 says. But wolves may also tend to avoid His team next plans to do a short-term roads with heavy traffi c. A study in the experiment on the space station that Connect with us April 2020 Mammalian Biology found will investigate micro gravity’s effects that wolves in Poland prefer to travel on developing mouse embryo s. The along high-traffi c forest roads when embryos will be stor ed for one to two

there was low human activity. weeks in freezers at –95° C. GRAPHIC NODE/UNSPLASH

34 SCIENCE NEWS | August 28, 2021

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_p35.indd 35 7/29/21 4:45 PM SCIENCE VISUALIZED

Water velocity (m/s)

0 0.11

How a sea sponge manipulates ocean currents The glassy skeleton of a ’s-flower-basket is an eye-catching, lacelike chamber. But this glass sponge (top-down view at left) isn’t all show. Simulations reveal how the sponge’s intricate, porous structure alters the flow of water, helping the deep- sea animal endure unforgiving ocean currents and perhaps feed and reproduce, researchers report in the July 22 Nature. Previous studies have found that the gridlike construction of a Venus’s- flower-basket (Euplectella aspergillum) is strong and flexible. “But no one has ever tried to see if these beautiful structures have fluid-dynamic properties,” says mechanical engineer Giacomo Falcucci of Tor Vergata University of Rome. Using supercomputers, Falcucci and colleagues simulated how water flows past and through the sponge (gray at left in the simulation above). Its shape creates a gentle zone of slower water that flanks the sponge, the team found. As a result of this gentle-zone creation, the sponge’s body endures less stress. If the sponge were a solid cylinder, the water would form a chaotic wake just past the animal that could jostle it, Falcucci says. Vertical cross sections (blue bars) divide the simula- tion into zones with different flow activity. The team also found that ridges that spiral around the outside of the sponge

cause water inside to slow and swirl, forming particle-trapping vortices. Food and PHOTO STOCK 2021; AGEFOTOSTOCK/ALAMY NATURE reproductive cells that drift into the sponge would become trapped for up to twice as long as in the same sponge without ridges, simulations showed. That lingering could help the filter feeders catch more plankton. And because Venus’s-flower- baskets can reproduce sexually, it could also enhance the chances that free-floating sperm encounter eggs.

It’s amazing that such beauty could be so functional, Falcucci says. — Nikk Ogasa ET AL / G. FALCUCCI TOP: FROM

36 SCIENCE NEWS | August 28, 2021

scivis.indd 36 8/11/21 11:52 AM At Lehigh University, you’ll find hands-on, creative and interdisciplinary experiences that will challenge you and prepare you to solve complex problems in real-world situations. Our world-class faculty and rigorous academic programs will have you ready for success in whatever STEM field you choose.

College of Arts and P.C. Rossin College of Intercollegiate Sciences Engineering and Applied Interdisciplinary Programs Astronomy Science Computer Science and Astrophysics Applied Science Business (CSB) Behavioral Neuroscience Bioengineering Integrated Degree in Biochemistry Chemical Engineering Engineering, Arts and Biology Civil Engineering Sciences (IDEAS) Chemistry (B.S. and B.A.) Computer Engineering Integrated Business Cognitive Science Computer Science (B.S.) and Engineering (IBE) Computer Science Electrical Engineering Dual-Degree/Accelerated (B.S. and B.A.) Engineering Mechanics Earth & Environmental Sciences Engineering Physics Programs Mathematics Environmental Engineering Arts & Engineering Molecular Biology Industrial & Systems Pharmaceutical Chemistry Engineering College of Health Physics Materials Science & Statistics Engineering Population Health Mechanical Engineering

This is a partial list of Lehigh’s majors and programs. For the full list, please visit lehigh.edu/majors.

lehigh.edu/admissions [email protected]

ISEF-STEM-ad-2021-color.indd 1 7/20/21 3:12 PM _C3.indd 3 8/11/21 1:55 PM 6:1 1,200+ 24/7 student-to-faculty ratio science, math, and hours the Center for Engineering engineering labs Innovation and Design (CEID) on campus is open for student use 200+ summer fellowships 2:1 >40% for undergraduate of Yale College students science and engineering student-to-faculty ratio in STEM majors graduating with a students annually STEM major are women

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