SI March April 2010 pgs:SI J A 2009 1/22/10 11:47 AM Page 29

SCIENCE WATCH K E N N E T H W. K R A U S E

An Eye for the Ladies

volutionary scientists made 2009 a Carnegie Museum of Natural History in megacanina. Ganlea possessed a distinc- remarkable year for the fairer sex. Pittsburgh, Pennsylvania, declared, “Ida’s tive feeding adaptation characteristic of ELet’s start with masil - a fine fossil, but she’s not the missing modern saki monkeys from the Amazon lae—remember “Ida”? On May 19 the link.” Arguing that she “fails miserably” Basin of South America: an extremely world was introduced to the purported to display any anthropoid features that large canine tooth used to pry open tough “missing link” between primitive pri- evolved after that group’s split from tropical fruits to access their seeds. mates and —an exceptionally well-preserved, forty-seven-million-year- old cat-sized fossil belonging to an extinct branch of early called adapi- forms. As an international team led by Jo/rn Hurum of the University of Oslo, Norway, released the PLoS One paper, Ida was ceremoniously unveiled to an enthu- siastic audience that included New York City Mayor Michael Bloomberg at the American Museum of Natural History. A book and documentary film, both dub - bed The Link, quickly followed. Hurum claimed that although Ida m o c plainly resembled some prosimians s w e N

(lemurs, tarsiers, and their extinct ances- : o t o h

tors), her fossil also revealed anthropoid- P like (and thus -like) features, The Ida fossil. This was thought to be at the root of anthropoid evolution, when primates were first devel- including a partially fused lower mandible oping the features that would evolve into our own. and a foot bone called a talus. She also other primates, Beard bluntly character- Compared to adapiforms like Ida, Beard lacked the “toothcomb” and “grooming ized the Ida unveiling as “unbridled concluded, Asian amphipithecids like claw” more typical of lemurs. Because she hoopla” and warned his fellow scientists Ganlea were much stronger candidates for was recovered from an oil shale pit in against having their work “evaluated on the coveted title of ancestors to the Messel, Germany, Hurum’s team argued the same basis as the advertising cam- anthropoids. that Ida also challenged the more conven- paign for the next world tour of the tional wisdom that anthropoids had orig- Rolling Stones.” Kenneth W. Krause is a contributing edi- inated in . On July 1 Beard published an article tor and science news columnist for the But criticism rained fast and furiously in the online Proceedings of the Royal SKEP TICAL INQUIRER, and a contributing on Ida’s well-publicized parade. In the Society B that introduced a thirty-eight- editor and books editor/columnist for the May 30 New Scientist, Chris Beard, cura- million-year-old fossil from My - Hu manist. He may be contacted at tor of vertebrate paleontology at the anmar (formerly Burma) called Gan lea [email protected].

SKEPTICAL INQUIRER March / Ap ril 2010 29 SI March April 2010 pgs:SI J A 2009 1/22/10 11:47 AM Page 30

In “Weak Link,” Kate Wong’s short brightly upon two much younger ladies— eclipse the ever-brightening limelight piece in the August issue of Scientific one from Aramis, Ethi opia, and the other cast upon the little lady of Flores, Indo - American, Robert Martin from the Field from the Indonesian island of Flores. nesia, known as LB1. About a meter tall Museum in Chicago and Richard Kay Clocking in at about 4.4 million with a chimp-sized brain, LB1 and her from the paleontology department at years old, Ardipithecus ramidus may rev- fellow “hobbits” were recovered late in Duke University piled on to the now- olutionize our long-held assumptions 2003 from Liang Bua cave sediments crowded anti-Ida bandwagon. Martin about the evolution of bipedality and dating from 95,000 to 15,000 years ago pointed out that fused lower jaws had the physiology of the six million year old (see my article, “Pathology or Paradigm evolved independently in several other last common ancestor between humans Shift?” SI, July/August 2009). From the , including lemurs, but were and chimpanzees. “Ardi,” a fairly com- beginning, a small minority of scientists not present in the earliest anthropoids. plete skeleton found among thirty-six or have disputed the majority’s conclusion Like Beard, Kay judged that fossil evi- more individual African specimens, did- that LB1 represents Homo floresiensis, a dence of primitive Asian primates n’t knuckle-walk or swing through the species entirely separate from our own. proved that the lady from Messel was trees like an ape. Instead, she probably These detractors have hypothesized that not a direct ancestor of monkeys, apes, walked upright on the ground but also the hobbits are merely pygmoid or or humans. used her opposable big toes to negotiate pathological H. sapiens, and what re- Finally, in the October 22 Nature, a intermediate tree limbs on all fours. mains of the debate has, unfortunately, team led by Erik Seiffert at Stony Brook Ardi is one of just six skeletons dated grown somewhat venomous. University in New York compared the to more than a million years old and the Even so, the new-species proponents fossil traits of two adapiforms, Ida and the only one older than Lucy (Australo - have recently fortified their position. Indeed, the Journal of Human Evolution devoted an entire edition to more evi- dence and arguments in favor of H. flo- resiensis. Guest-edited by Michael Mor - wood, LB1’s Australian co-discoverer, The gods of paleoanthropology appear to be and William Jungers, a prominent an- smiling brightly upon two much younger ladies atomist at Stony Brook University, the November 2009 issue featured peer- —one from Aramis, Ethiopia, and the other reviewed articles analyzing much of the from the Indonesian island of Flores. hobbits’ tiny bodies, including their brains, teeth, mandibles, and limbs, along with their stone-flaking technol- ogy and environmental milieu. Doubtless, the evolutionary stakes over the Flores hominins are extremely high. thirty-seven-million-year-old Afra dapis pithecus afarensis) to be published. Tim Conventional wisdom has long held, first, longicristatus, to those of more than one White and others from the Middle that the Neanderthals were the last group hundred other living and extinct pri- Awash research group discovered these of hominins to cohabit the earth with H. mates. After evaluating 360 morphologi- wonderful fossils beginning in Decem- sapiens and, second, that no human cal features, Seiffert concluded that ber 1992. But only recently were eleven species had ventured from the confines although the adapiforms shared certain papers and author summaries dissecting of Africa prior to H. erectus. The hobbits traits with anthropoids—the loss of a the amazing details of Ardi’s anantomy, effectively challenge both paradigms, third upper and lower premolar, for diet, habitat, and evolutionary signifi- according to Jungers and his co-worker example—those characteristics had arisen cance finally released in the October 2, Karen Baab. In the December 2009 issue more than once among primates and were 2009, Science. An “unpredicted and odd of Significance, they discuss evidence “most parsimoniously interpreted as evo- mosaic,” writes White’s team, Ar. ramidus suggesting that LB1 may have descended lutionary convergences.” Ida was not a “is so rife with anatomical surprises that from a species much smaller and more haplorhine anthropoid, in other words, no one could have imagined it without ancient than H. erectus. but rather a strepsirrhine (a group includ- direct fossil evidence.” Ardi’s discovery Statistical analyses of skull shapes, for ing lemurs and lorises) that “left no was named Breakthrough of the Year in example, “find modern humans in one known descendants.” the December 18 Science. Deserving far grouping,” the authors say, “micro- Hurum’s team continues to defend more attention than I can deliver here, cephalic humans in another, and the Ida’s status as the so-called “missing link,” Ardi and her captivating cohorts will be hobbit, together with ancient hominins, but her claim to fame appears to be falling featured more prominently in an upcom- in a third.” They found that hobbit bod- on increasingly deaf ears. Even so, the gods ing issue of the SKEPTICAL INQUIRER. ies were unique too. The Flores speci- of paleoanthropology appear to be smiling But no fossil hominin’s gleam can mens were “far stockier” than any mod-

30 Volume 34, Issue 2 SKEPTICAL INQUIRER SI March April 2010 pgs:SI J A 2009 1/22/10 11:47 AM Page 31

ern human, including pygmies, and which are associated with fertility and But we shouldn’t be too surprised if although their arms were about the same intelligence. By comparison, the tiny Y over the next few centuries or so we notice length as those of pygmies, their legs chromosome stores just eighty-nine that the ladies sitting at those tables have were much shorter. To Jungers and genes and the average autosome only begun to change. In an attempt to show Baab, this peculiar ratio implies an evo- about eight hundred genes. Second, that natural selection continues to mold lutionary retention rather than a reversal because of how the X is passed down the human species despite modern medi- because selective forces would probably between generations, some grandmas are cine’s benign and insulating influences, not reverse more economical features biologically closer to some grandkids and that we can predict changes to spe- like long limbs. Finding no special than to others. While MGMs are 25 per- cific traits in the short term, Yale Uni - resemblances between H. erectus and the cent X-related to both boys and girls, versity biologist Stephen Stearns pored hobbits, the authors emphasize the pos- PGMs are 50 percent X-related to grand- over results from the Framingham, sibility of a pre-erectus out-of-Africa trek daughters but 0 percent to grandsons. Massa chusetts, Heart Study, which, initi- by “Homo habilis or some as yet un - According to Knapp’s conclusions, ated in 1948, is the longest-running known ancient species.” these genetic inequities produce very multigenerational analysis in medical his- And now everyone’s grandma is in the serious real-world effects. The team ana- tory. In October 2009, Stearns’ team evolutionary spotlight too, though some lyzed sex-specific grandchild survival reported their results in the Proceedings of grandkids will surely be more impressed rates among seven modern and histori- the National Academy of Sciences. with the news than others. Natural selec- cal societies across the globe (in Japan, The original heart study included tion, of course, continues to pose tough Germany, England, Ethiopia, Gambia, thousands of Framingham residents— questions for all scientists. How altruism and homosexuality evolved are usually mentioned first. But what about post- menopausal longevity; why do women— unlike other primates and most mam- mals—live long past their child-bearing After comparing certain medically significant years? A team led by University of traits between generations, and controlling for Cambridge anthropologist Leslie Knapp has offered the “X-linked grandmother about fifty environmental factors, Stearn’s team hypothesis”—an exceptionally interest- claimed the ability to forecast the rate of ing, if for some quite troubling, explana- tion recently published in a Proceedings of evolutionary change ten generations forward. the Royal Society B article titled “Grand ma Plays Favourites.” Scientists had previously proposed that grandmothers perpetuate their genetic material by generally caring for their grandchildren. But according to Malawai, and Canada). Amazingly, they most of Northern European descent— Knapp, because those earlier studies failed discovered that regardless of cultural cir- and more than nine hundred family to distinguish between maternal and cumstances, the effect of grandmother trees. Stearns considered only the paternal grandmothers (MGMs and presence on grandchild mortality closely women for lack of paternity informa- PGMs), they “found no correlation” corresponds to the degree of X-related- tion. After comparing certain medically between grandmother presence and ness—a PGM, in other words, will actu- significant traits between generations, grandchild survivorship. Moreover, only ally increase a girl’s (yet decrease a boy’s) and controlling for about fifty environ- two prior studies distinguished between chance of survivorship. mental factors, his team claimed the male and female grandchildren. Sug - This, of course, is not to imply that ability to forecast the rate of evolution- gesting cultural mechanisms for their grandmas intentionally discriminate ary change ten generations forward. results, those studies revealed that MGM against some of their grandkids. Al - Framingham women of the future, presence had a positive effect on both though the mechanism is surely an un - they predicted, will be slightly “shorter sexes, but that PGM presence had a posi- conscious one, Knapp could only guess and stouter” with lower total cholesterol tive effect on girls and a negative effect on how it really works—perhaps through a levels and systolic blood pressures, and boys. Query: if the causes were merely child’s pheromones or physical resem- they will give birth to their first child cultural, why the difference? blance, for example. Nevertheless, her sooner and reach menopause later. In For two important reasons, Knapp team’s results were impressive, to say the other words, the ladies will be healthier looked to the X chromosome for clues. least, and just might provoke some inter- and enjoy longer periods of reproduc- First, the copious X contains 1,529, or 8 esting conversations across holiday din- tive viability. I wonder—will Barbie get percent, of all human genes, many of ner tables this year. a makeover too? !

SKEPTICAL INQUIRER March / April 2010 31