The Peter Buck Fellowship Program

Progress Report

May 2, 2012 The Peter Buck Fellowship Program

In April 2010 Dr. Peter Buck generously created an endowment to support a fellowship and internship program at the Smithsonian Institution’s National Museum of Natural History. The Peter Buck Fellowship Program has positioned the Museum to become a leader in the training of emerging and early-career scientists. It is an ambitious program that, once fully established, will support approximately 20 fellows at any given time. With this gift, Dr. Buck has made it possible for the Museum’s tradition of scholarship in biological and geological sciences to evolve and advance for generations to come.

Class of 2011 In April of 2011 the Museum Fellowship Selection Committees in Anthropology, Earth Science, and Systematics and Evolutionary Biology selected 11 candidates for the initial cohort of Peter Buck Fellows. All of them are now in residence at the Museum, conducting field work, or studying collections at partner institutions. They are all pursuing careers in science; nine are postdoctoral fellows and two are predoctoral fellows. Studying everything from the evolution of flowering plants to the composition of Earth’s lower mantle, they are remarkable individuals with bright, hungry minds.

Class of 2012 In April of 2012 the Museum chose nine Buck Postdoctoral Fellows from among 84 eligible applications. The applicants represented 54% of the Museum’s total fellowship applicant pool. All requested longer-duration fellowships: more than one year for predoctoral candidates and two years for postdoctoral candidates. Prior to the beginning of the Peter Buck Fellowship Program, the Museum was able to offer very limited opportunities for two and three-year fellowships. A chief aim of the Buck Fellowships is to give young scholars extended periods of study at the Museum, so that we can benefit from their work and fresh perspectives, and they can learn from our experience and collections. The multi-year fellowships are also more appealing to students and help us attract the most talented candidates.

The Peter Buck Fellowship Program has infused the Museum with new energy and life. The fellows are actively using the Museum’s collections and laboratories, tapping the knowledge of their advisors, and sharing new ideas with staff and the public. We are proud to be part of their growth and development. This report chronicles some of the highlights of the initial group of Peter Buck Fellows and introduces the next class. A complete list of the fellows is included at the end of the report.

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Peter Buck Fellows Class of 2011

The first class of Peter Buck Fellows has conducted research around the world, from Lake Malawi in the East African Rift Valley to the Essequibo River in Guyana (above). Photo by J. Sosa-Calvo

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Dr. Richard S. Barclay, Paleobotanist

Postdoctoral Fellow: January 2012 – January 2015

Research Title: A Geologic Analogue for Modern CO2 Increase: Reconstructing Atmospheric CO2 through the Paleocene-Eocene Thermal Maximum

Advisor: Scott Wing (Curator of Fossil Plants)

Richard Barclay knows he is in the presence of a quality fossil leaf when he can count its stomata. These are the

microscopic pores that allow plants to take in CO2 and release water. Scientists have discovered that they also

reflect changes in atmospheric CO2 concentrations; as CO2 rises over time, the number of stomata on the leaves decrease each year on freshly grown leaves. Barclay is analyzing the stomata in the Museum’s fossil leaf

collection to try to reconstruct the CO2 conditions that existed 56 million years ago. Known as the Paleocene-Eocene Thermal Maximum (PETM), this was a period of rapid global warming that was caused by a large release of carbon. It has become a focal point for researchers trying to understand the possible effects of current CO2 increases. Much of what scientists know about CO2 during the PETM comes from analyzing marine cores. Barclay’s investigation will be the first attempt to estimate CO2 changes using fossil plants.

Since he arrived in January 2012, Barclay has laid the groundwork for his research. He has surveyed Museum curator Scott Wing’s vast collection of fossil plants, unearthed from Wyoming’s Bighorn Basin over the past three decades. Many of them are well-preserved leaves, which Barclay needs in order to accurately count the stomata. He will focus on those related to modern Ginkgo and Laurel plants. Both plant groups are known to respond to changes in atmospheric CO2, and will provide complementary and independent evidence for the magnitude of any changes observed in the CO2 reconstructions. In July Barclay will visit Wyoming to learn

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more about the localities where these specimens came from and collect additional fossils and rock samples. In the coming year he expects to have a preliminary reconstruction of CO2 during the PETM.

Additional Highlights o Barclay will also extract and analyze plant fragments from rock samples to help augment the fossil leaf record. He has spent time in the Museum’s sedimentology lab preparing for this work and testing his rock-macerating methods.

o In late February Barclay attended the Geobiology Symposium at the University of Pennsylvania and shared some of his previous work on a marine extinction event 95 million years ago, where much of the world’s oceans became inhospitable to life due to low-oxygen conditions. The driving mechanism was volcanism, which exhaled massive quantities of carbon into the atmosphere. In many ways this mimics what occurred during the PETM, but also there were major important differences. Barclay’s presentation explored the similarities between the two events, focusing on the effect of massive releases of carbon on the stable carbon isotope record.

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Dr. Emily Goble, Paleoanthropologist

Postdoctoral Fellow: September 2011 – September 2013

Research Title: Miocene and Pliocene East African Fauna Relative to Global Climate Change.

Advisors: Richard Potts (Peter Buck Chair of Human Origins) and Matthew Tocheri (Paleoanthropologist, Human Origins Program)

In the National Museums of Kenya, some 2,700 fossil specimens of pigs, hippos, bovids, and other non-hominin mammals eagerly await paleoanthropologist Emily Goble. The fossils come from excavations conducted over the years by Smithsonian curator Rick Potts and his colleagues. They are from Kenya’s Homa Peninsula and may provide evidence about how changes in global climate impacted local environments and animal evolution 2 to 6 million years ago. It was during this timeframe, the late Miocene and Pliocene, that scientists have evidence of a “bushy” lineage for the human family, with each lineage utilizing the landscape in different ways. Earlier scientific thinking supported the idea of our genus Homo emerging due to an increasingly arid and savanna-like landscape but new evidence suggests a more mosaic environment that was perhaps under continuous change and exploited by Goble participating in the “Scientist is In” program and talking with the more generalist hominins. visitors in the David H. Koch Hall of Human Origins. Goble joined Potts, who directs the Museum’s Human Origins Program, to create a more detailed picture of the Homa Peninsula’s paleoenvironment through analysis of the fauna. In August she will travel to Nairobi to spend two months studying the site’s fossil mammal collection. She will identify the animals that lived there, their abundance, when they first appeared at the site, and when they left. When looked at against the backdrop of known global climate cycles, a pattern may emerge that will help us better understand how climate change plays out on local landscapes. Eventually Goble will compare her findings from the Homa Peninsula with another locality in Kenya. These deep-time investigations will inform our predictions for how existing ecosystems may change in the future.

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Additional Highlights o To prepare for her work in Kenya, Goble has examined related fossil mammals housed at the Museum Support Center in Maryland. She is trying to develop new methods for identifying hippos, rhinos, and horses at the species-level. Current practices require having a complete skull, which is not always the case for specimens that have been collected. Goble is trying to determine if other bones could be used to identify the specific species.

o Goble has become actively involved in the Museum’s education programs. She has participated in the “Scientist is In” program where she talks with visitors in the Hall of Human Origins. She is also helping develop some of the activities for the new Center for Science Education.

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Dr. Brent Grocholski, Geophysicist

Postdoctoral Fellow: September 2011 – August 2014

Research Title: The Lower Mantle and the Earth’s Water Cycle

Advisors: Elizabeth Cottrell (Director, Global Volcanism Program) and Jeffrey Post (Geologist, Division of Mineralogy)

Scientists know that the Earth’s upper mantle contains more water than the global ocean. How the water cycle works in the lower mantle—some 700 to 3,000 km below the Earth’s surface— remains a mystery. It is important to understand because it may affect plate tectonics and other geophysical properties that help shape Earth. Brent Grocholski has designed an experiment that he hopes will provide some insight into how water interacts with two minerals: magnesium- silicate perovskite and postperovskite. Both are key ingredients in the lower mantle. Grocholski has conducted previous experiments on these minerals. He recently published a paper in the Proceedings of the National Academy of Sciences that suggested that, contrary to the prevailing hypothesis, the lower mantle may not be one homogeneous, well-mixed layer. Now he will examine these minerals and add water as a variable, hoping to complete the picture as to how water has cycled through the planet over geologic time and Examples of pyroxene crystals grown in the High Pressure potentially explain some of the strange laboratory at NMNH. The crystals were synthesized with water features of the lower mantle that may be present at pressure conditions equivalent to 45 km depth in the connected to presence of water. Earth. The rainbow colors are not natural, but an interference phenomenon that is due to changes in the thickness of the minerals.

In June Grocholski and advisor Liz Cottrell will head to the Brookhaven National Laboratory in New York to use the synchrotron. Grocholski has been preparing the starting materials for the experiment using a piston cylinder and other equipment in Cottrell’s lab. He will use the starting material to fabricate tiny crystals of hydrous perovskite and postperovskite. Subjecting them to synchrotron radiation, he will measure changes in their chemical and physical structure, paying close attention to how much water the minerals can dissolve under extreme conditions. A self- described experimentalist, Grocholski seeks to make accurate measurements before interpreting them in a geophysical context. In the process, he hopes to advance our understanding of the Earth’s largest, yet most poorly understood, layer of the planet.

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Additional Highlights o Grocholski was the lead author of the paper, “Mineralogical Effects on the Detectability of the Postperovskite Boundary.” It was published in the Proceedings of the National Academy of Sciences on February 14, 2012.

o Grocholski organized a session on the Earth’s heterogeneous mantle at the American Geophysical Union’s fall meeting, the largest annual international gathering of Earth scientists. He shared his latest research in a talk entitled, “Mantle Heterogeneity and the D" Discontinuity.”

o “The Surprising Appearance of Highly Metastable Silica in Martian Meteorites,” was the title of a talk Grocholski gave at the Geological Society of Washington in October, 2011.

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Dr. Alison Hamilton, Evolutionary Biologist

Postdoctoral Fellow: September 2011 – September 2013

Research Title: Evolutionary Diversification of a Radiation of Tree Skinks in the Isolated Islands of Oceana.

Advisors: Kevin de Queiroz (Research Zoologist and Curator, Amphibians and Reptiles) and George Zug (Curator Emeritus, Amphibians and Reptiles)

Alison Hamilton has discovered new lizards in the wild and in the National Museum of Natural History’s collections. With more than 570,000 amphibian and reptile specimens, Hamilton and curator emeritus George Zug knew the collections contained “unrecognized diversity.” Since 2010 the two have been searching the collections for lizards from the South Pacific. A large tree skink from Rarotonga, Cook Islands was one of the first specimens that caught their attention.

The skink was collected in 1984 and was known to be a member of the genus Emoia. After a careful analysis of its genetics and morphology, Zug and Hamilton concluded the skink was a new species. They named it Emoia tuitarere. In Cook Island Maori, Hamilton collecting lizards on the South Pacific archipelago of Vanuatu. She is “tuitarere” means “wanderer, pilgrim, stranger, alien,” which investigating how new species evolve on hints at the skink’s relatively recent colonization of Rarotonga. islands and how diversity is maintained. That evolutionary history is what interests Hamilton. Her

research is aimed at understanding how and why new species evolve on islands and how diversity is maintained over time. One of her underlying questions is whether and how the environment of an island and its available resources help drive speciation or if the changes that lead to new species are purely random and simply result from the extreme isolation.

In the coming months, Hamilton will finish describing seven of the lizard species she discovered during field collections in the Pacific archipelago of Vanuatu. Five are skinks and two are geckos. Hamilton is building a detailed dataset with One of the new species of Emoia tree skinks that information on Emoia skinks. It will contain their Hamilton discovered and is describing. She found it on the island of Tanna, in southern Vanuatu. genetic makeup, key physical features, and details

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about their local habitat. She hopes to find a pattern that reveals how speciation happens in the South Pacific. She will eventually compare her data with those collected by her advisor Kevin de Queiroz and other researchers who have studied lizard evolution in the Greater Antilles and Madagascar.

Additional Highlights o Hamilton helped assess the status of lizards in the South Pacific for the International Union for Conservation of Nature’s (IUCN) Red List. The Red List identifies the species most at risk of extinction and is a tool that governments, resource managers, and others can use to guide protection efforts. Hamilton participated in the assessment last summer and is making her final comments on the recommendations for Red List species.

o When Hamilton conducts field work this summer in Indonesia, she will teach a 5 week class at Udayana University on molecular ecology to Indonesian scientists. It is part of a capacity-building program, funded by the National Science Foundation and the U.S. Agency for International Development, aimed at training the next generation of Indonesian scientists and giving them cost-effective tools and methods for their labs and classrooms.

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Nathan Andrew Jud, Paleobotanist

Predoctoral Fellow: June 2011 – May 2013

Research Title: The Angiosperm Invasion of North America: Quantitative Analysis of the Rise of Flowering Plants

Advisors: Scott Wing (Curator of Fossil Plants) and William DiMichele (Curator of Fossil Plants)

For about a century paleontologists have picked through the Cloverly Formation. The rocks, which run along the border between Montana and Wyoming, date back approximately 140-105 million years. They have produced some of the more famous dinosaur discoveries of the Lower Cretaceous. But Nathan Andrew Jud is not looking for the next Deinonychus, he is on a quest for fossil water lilies, magnolias, and other flowering plants. He found hundreds of them during an expedition last summer. Jud will use these, along with the Museum’s collections, to search for evidence about the evolution of plants. For most of Earth’s history conifers, ferns, and other gymnosperms dominated the vegetation. But today, flowering plants, or angiosperms, reign supreme by almost any measure. That change began sometime during the Early Cretaceous. Jud wants to know how this transition unfolded. The rocks and plant fossils of the Cloverly Formation may hold the answer.

Jud has been gathering fossil plants from different habitats within the Cloverly Formation: lake margins, swamps, ponds, and rivers. The specimens come from three distinct time periods and should help paint a picture of how the local vegetation changed as early flowering plants evolved. He is still gathering evidence, but has been surprised by the diversity of flowering plants he has found in all the habitats. His Jud, collecting fossil plants in the Cloverly Formation, which straddles the border between Montana and Wyoming. preliminary analysis suggests that around 110 million years ago relatives of redwood trees and ferns covered much of what is now northern Wyoming; but diverse, rare flowering plants infiltrated all of the different habitat types.

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This summer Jud will make one final collecting trip to Wyoming. He will begin the final assessment of his data in earnest this fall.

Additional Highlights o Jud drafted a paper describing a new species of water lily. He suggests that the water lilies and other aquatic flowering plants achieved worldwide distribution early in their evolution.

o In December 2011, Jud launched his own blog, “reallyoldplants: paleobotanical adventures.” You can find it at reallyoldplants.wordpress.com.

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Jeffrey Sosa-Calvo, Entomologist

Predoctoral Fellow: August 2011 – August 2013

Research Title: Revision of the Non-Leaf-Cutting Fungus-Farming Ant Genus Myrmicocrypta Fr. Smith (Formicidae: Attini), with Morphological and Molecular Phylogenetic Analyses of Ants and Fungal Cultivars

Advisors: Ted Schultz (Department Chair and Research Entomologist) and Sean Brady (Research Entomologist)

When Jeffrey Sosa-Calvo collected 34 ant colonies in Brazil last fall, he brought a supply of Cream of Rice Cereal and an extraordinary amount of patience. The white breakfast food serves as bait and makes the tiny Myrmicocrypta ants easy to track to their nests. These are fungus farmers from the tribe Attini; they take flower parts, insect frass, and other organic detritus into their nests and use them as substrate to grow fungus gardens that they use for food. Fungus-growing ants are keystone players in local ecosystems, participating in decomposition, cycling of nutrients, and nitrogen fixation; their presence can be an indication of the overall health of the environment. Sosa-Calvo is exploring the phylogenetic relationships of the species within the genus Myrmicocrypta. In addition to this, he is investigating the phylogenetic relationships of the Sosa-Calvo excavating a colony of Mycetagroicus fungus gardens cultivated by species of Myrmicocrypta, cerradensis, in Estação Ecológica do Panga, which could provide important information about the Uberlândia, Minas Gerais, Brazil. The chamber early evolutionary history of farming behavior in with the fungi was located almost four meters from the surface. Photo: Ted R. Schultz fungus-growing ants.

Of the more than 13,000 known species of ants, only about 250 practice agriculture. Agriculture has evolved in only four animal groups: humans, termites, bark beetles, and ants. In ants, this behavior evolved once about 50 million years ago. Since then, the fungus-growing ants have developed a range of farming practices. The tribe is currently divided into two big groups: the higher and the lower fungus-growers. Higher fungus-growing ants, which include leaf-cutter ants, raise a highly domesticated fungus that is in a strict symbiosis with the ants. Neither can live without the other. Lower fungus-growing ants, which include the Myrmicocrypta species that Sosa-Calvo studies, depend on their fungi, but the fungi can live quite well without the ants.

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Sosa-Calvo and his advisor Ted Schultz want to determine whether or not certain widespread species of Myrmicocrypta are faithful to particular fungi, or whether they are able to cultivate more than one species. This will help them understand whether there is a connection between acquiring new fungal cultivars and speciation in fungus-growing ants. In the coming year, they will conduct extensive DNA analyses of the fungus-farming ants and fungi that they collected in Brazil A colony of Myrmicocrypta cf. squamosa with workers and the queen and other countries in South America. in the fungal garden. Brasilia, Brazil. Photo: J. Sosa-Calvo This research, combined with more traditional morphological study, will help them paint a more accurate picture of ant evolution.

Additional Highlights o During his collecting trip to Brazil, Sosa-Calvo and his advisor discovered a lower fungus-growing ant species that, contrary to all prior experience, is growing the fungal cultivar known only from the higher leaf-cutting fungus-growing ants. It is a significant discovery that Sosa-Calvo will continue to work on in the coming months.

o In November and December of 2011, Sosa-Calvo collected ants in Guyana as part of the Smithsonian’s Biological Diversity of the Guiana Shield Program. The program aims to study, document, and preserve the rich flora and fauna of northeastern South America.

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Dr. Daniel Thomas, Paleobiologist

Postdoctoral Fellow: January 2012 – January 2014

Research Title: Diet and Feather Color of Fossil Birds Using Raman Spectroscopy

Advisors: Helen James (Curator in Charge, Birds) and Matthew Carrano (Curator of Dinosauria)

The fossil record for birds is almost monochromatic. Black, brown, gray and white are the only colors scientists have been able to tease out of fossil feathers. Daniel Thomas hopes to change this. He is a paleobiologist and is trying to reconstruct fossil feather color using spectroscopy. Because color plays an important role in everything from mating to self-defense, Thomas’ findings could add an important dimension to our understanding of bird evolution.

Since he arrived in January 2012, Thomas has been examining the Museum’s collection of modern feathers. His primary tools are Raman spectroscopic instruments at the Smithsonian’s Museum Conservation Institute, in Maryland. These have relatively weak lasers that help reveal the chemical makeup of the feather color. Thomas is building a library of spectra from modern feathers that he will use as a reference when he begins his work on the fossil feathers. Among the specimens he hopes to examine is a piculet (Picumnus sp.) feather preserved in amber. Thomas will initially focus on the birds that lived during the Paleogene, some 65 to 23 million years ago. A year from now, Thomas hopes to know whether or not it is possible to find evidence of colors other than black, brown, gray, or white. Daniel will then switch focus to examine the diet of fossil seabirds, using the same analytical instruments that he is currently using to study feathers.

Additional Highlights o Thomas has also investigated the chemistry and microstructure of dinosaur bones. Some of his research was published in the April 2012 issue of The Anatomical Record. The paper, “Hadrosaurs Were Perennial Polar Residents,” presented evidence of dinosaurs that lived in the forested Arctic year round, even during the dark of winter.

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o During his analysis of modern birds, Thomas became fascinated with the crest feathers found on the Macaroni penguin (Eudyptes chrysolophus). He says they have a pigment that scientists have not been able to describe. It is yellow, but entirely different from the color found in canaries and other yellow birds. Thomas’ preliminary investigations indicate that an unknown chemical is coloring these feathers. Perhaps once he finishes his primary investigations, he will study this chemical in greater depth.

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Dr. Bert Van Bocxlaer, Evolutionary Biologist

Postdoctoral Fellow: April 2012 – March 2014

Research Title: Patterns of Diversification in an Endemic Clade of Freshwater Snails in the East African Rift Lake Malawi

Advisors: Ellen Strong (Curator of Mollusca, Invertebrate Zoology) and Gene Hunt (Curator of Ostrocoda, Paleobiology)

At the southern end of Lake Malawi, in the East African Rift Valley, several species of freshwater Bellamya snails dwell just above their buried fossil ancestors. They are preserved in layers and layers of lake sediments. Evolutionary biologist Bert Van Bocxlaer has dug through many of these to gather some 40,000 fossil snails from 17 shell beds. The oldest shell bed dates back almost 11,000 years. The fossils are young, but the combination of fossil ancestors and extant descendants offers Van Bocxlaer a rare opportunity. Using traditional paleontology techniques, DNA analysis, and other methods, he is teasing out a detailed, almost incremental, account of how Bellamya species evolved and adapted to life in Lake Malawi. His findings may reveal a broader pattern of evolution that could be applied to other organisms.

Van Bocxlaer collecting Bellamya along In the coming year Van Bocxlaer will create an 11,000-year Lake Malawi in 2010. chronology of Bellamya. He will also begin investigating evolutionary divergence in the living snail species and link this with differences in their habitats. By studying how Bellamya species adapted to their respective habitats (e.g. with or without vegetation, different water depths, etc.) Van Bocxlaer aims to explain the causes of the evolutionary change observed in the fossils. For this work he will dissect snails of all Bellamya species in Van Bocxlaer has brought a number of Bellamya snails from Lake Malawi to his lab in Belgium. He the lake to examine their anatomy as well as the size is conducting “transplant experiments” to investigate the genetic basis of shell morphology.

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and number of offspring the females carry around. During a later phase, he will expand beyond the Lake Malawi drainage basin, to search for clues about how the snails have adapted to the Rift Valley’s geological development and the accompanying environmental changes throughout time.

Additional Highlights:

o When Van Bocxlaer’s team hunts for Bellamya, they also help monitor Lake Malawi and its direct surroundings for snail species that are known to spread the harmful bilharzia disease to humans.

o Van Bocxlaer is increasing the scientific capacity within Malawi. On his last field expedition he offered paid stipends to members of the Cultural and Museum Centre Karonga who preserve the cultural and natural heritage of Malawi and disseminate it to the Malawian people.

o Van Bocxlaer has conducted previous investigations in the Democratic Republic of the Congo. He recently designed a PhD project related to this work for one of his Congolese students. The student has been accepted to a program in Germany and will begin in 2013.

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Dr. Anne Wiley, Ornithologist

Postdoctoral Fellow: July 2011 – July 2013

Research Title: Variation in Individual Feeding Habits Through Time and Space: Gauging the Sensitivity of Seabirds to Changes in Prey Availability

Advisor: Helen James (Curator in Charge, Birds)

Reconstructing a 4,500-year portrait of life in the open ocean is riddled with obstacles. Chief among them is the fact that most of the marine fossil record from this period lies on the seafloor. Marine ornithologist Anne Wiley has turned to a winged animal for help: the Hawaiian petrel (Pterodroma sandwichensis). A pelagic seabird, P. sandwichensis forages thousands of miles out over the ocean and faithfully returns to its nesting grounds. Its fossil remains are scattered in caves and dunes Wiley observing a 600-year-old skull of a Hawaiian petrel throughout the Hawaiian Islands. Wiley discovered on Maui. has been analyzing these fossils—the oldest of which date back 4,500 years— to determine where in the food chain the petrels have been feeding. Because Hawaiian petrels feed over an area of the ocean larger than the continental U.S., changes in their diet can reveal shifts in oceanic food webs occurring at large spatial scales.

Last December Wiley obtained critical data that show that a significant shift in the bird’s diet occurred sometime within the past century. For thousands of years P. sandwichensis fed on fish and squid that were higher in the food chain. That changed sometime after 1914. Wiley discovered this from examining specimens that were collected at that time and housed in the Los Angeles County Museum. She obtained permission to remove small samples of bone from the birds for isotopic analysis. Wiley’s primary measurement is of the nitrogen isotope 15N, which bioaccumulates and therefore increases in concentration in predators that feed higher up the food chain. Today’s birds have a much lower concentration of 15N (or, lower nitrogen isotope signature) than those that foraged over the Pacific just 100 years ago. Wiley thinks this change in the petrel’s diet may be related to our industrialized fishing practices, which have advanced greatly during this time span. While it is difficult to tease out how modern fishing has impacted

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marine food webs, P. sandwichensis may give us important insight. Wiley is writing up her findings and will submit them for publication in the coming months.

During the next year Wiley’s investigations will focus more on living Hawaiian petrel populations. The seabird has been on the endangered species list since 1967. She wants to explore the links between the bird’s feeding habits and its population viability. She is studying what the birds consume throughout the year, hoping to learn the degree to which individuals can adapt to changes in available prey.

Additional Highlights One of the Hawaiian petrel study skins from 1914, along o Wiley shared her research with with its X-ray. Hawaiian wildlife managers who are trying to protect the endangered P. sandwichensis. Much of their work focuses on safeguarding nesting sites from cats and other introduced mammals, and Wiley is helping them better understand the petrel’s life at sea. In return, the wildlife officials are sharing important data and petrel remains with her.

o Wiley is collaborating with a team of researchers that is tagging P. sandwichensis with geo-locators to map the birds’ foraging expeditions.

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Dr. Michael Branstetter, University of California Davis

Postdoctoral Fellow: May 2012 – March 2014

Research Title: Phylogeny, Biogeography, and Life History Evolution in Ants: Insights from Stenammini (Hymenoptera: Formicidae: Myrmicinae)

Advisors: Ted Schultz (Department Chair and Research Entomologist) and Sean Brady (Research Entomologist)

Michael Branstetter will receive his PhD in June 2012 from the University of California Davis. He has published one paper, with several others in review. He has been team leader for several major entomological expeditions to Central America. He proposes to improve our knowledge of ant diversity by reconstructing the evolutionary relationships within the tribe Stenammini using a combination of molecular and morphological evidence. His work will test hypotheses about the evolution of seed harvesting and examine how this group diversified on different continents.

Eliécer Gutiérrez, City University of New York

Postdoctoral Fellow: May 2012 – March 2015

Research Title: Revealing the Evolutinary History of the Deer Genus Odocoileus, with Emphasis on the Cariacou Complex

Advisors: Dr. Kristof Helgen (Curator in Charge, Mammals) and Jesus McDonald (Research Geneticist, Smithsonian Conservation Biology Institute)

Eliécer Gutiérrez received his PhD in early 2012 for his work documenting the evolution of Latin American marsupials. He has produced eight scientific publications, including important taxonomic revisions of marsupials, rodents, and bats. He proposes to study the evolutionary relationships of South American whitetailed deer, an important group from a conservation and wildlife management perspective.

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Peter Buck Fellows Class of 2012

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Bonnie Blaimer, Ph.D., University of California at Davis Postdoctoral Fellow, Dept. of Entomology Advisors: Ted Schultz, Sean Brady

I will study the evolutionary processes that have shaped ant biodiversity in Madagascar, a biodiversity hotspot. Before coming to the Smithsonian I will collect and inventory the ant species that occur in four habitats: dry forest trees, dry forest leaf litter, wet forest trees, and wet forest leaf litter. At the Museum I will reconstruct the evolutionary relationships of around 325 ant species from all four habitats using DNA from three nuclear genes, then integrate the information on evolutionary relatedness with ecological data. I hope to understand, for example, if closely related ants tend to live in the same habitats or, conversely, if they occupy different habitats as a result of competition for resources. I hope my conclusions will inform a more general understanding of the evolutionary rules that govern the assembly of diverse communities of species living together in particular habitats.

Sara Casado-Zapico, Ph.D. University of Oviedo, Spain Postdoctoral Fellow, Dept. of Anthropology Advisor: Doug Ubelaker

Teeth may be preserved long after the death of an individual, and they can be used to estimate characteristics like age. During my postdoctoral fellowship I aim to develop a simple and precise method to estimate the age at death of unidentified cadavers using their teeth. Teeth show changes through life as a result of the effects of free radicals and oxidative stress, and in this project I will develop quantitative correlations between oxidative stress parameters and age. To demonstrate the reliability of the new method of age determination I will compare my results with classical and biochemical methods to estimate the age at death of individuals from their teeth. Furthermore, I will analyze the differences between populations with each methodology.

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Frederick Davis, Ph.D. University of Minnesota Postdoctoral Fellow, Dept. of Mineral Sciences Advisor: Elizabeth Cottrell

Basalts erupted from volcanoes on oceanic islands provide a window into the chemical character of Earth’s mantle. The global set of these basalts displays considerable chemical variation, some of which may be related to recycling of oceanic crust that was subducted and transported through Earth’s interior over hundreds of millions of years. Detecting the influence of recycled crust in the formation of these lavas would provide key insights into the processes by which material is exchanged between the Earth’s surface and interior, an important process in the chemical evolution of the planet. Several recent studies have suggested that certain trace elements, collectively called the “first-row transition elements,” may be used to identify basalts that were melted, in part, from recycled crust. However, many of these elements have not been analyzed routinely in basalts and mantle rocks, so their abundances in the mantle are poorly constrained. I have proposed to measure the concentrations of first-row transition elements in xenoliths, rocks carried from the mantle to the surface by erupted lavas, from the Smithsonian’s extensive collection. The results will improve our understanding of how the chemical variation of Earth’s interior leads to diverse lava compositions erupting around the world.

Torsten Dikow, Ph.D. Cornell University / American Museum of Natural History Postdoctoral Fellow, Dept. of Entomology Advisors: Norm Woodley (USDA), Sean Brady

Robber flies are a diverse group of predatory insects that live all over the world and are observed and studied by entomologists and amateurs alike. In spite of this interest there are few comprehensive treatments of the taxonomy and evolutionary relationships of particular groups of robber flies. During my fellowship I will record and analyze features of the flies' bodies and their DNA to reconstruct the evolutionary relationships of some 500 species of robber flies in a group called Leptogastrinae. I will also study the diversity of Leptogastrinae robber flies in Australia, oceanic islands of the Pacific, and Southeast Asia. These regions of the world are little studied, and new specimens available at the National Museum of Natural History as well as other collections in Australia and Hawaii will provide the opportunity to summarize what we know about existing species and discover and describe new species. The resulting species descriptions, photographs, and records will be published in peer-reviewed

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publications and will also be made available in public and online databases, increasing accessibility to scientists, students, and the public at large.

Jamie Fergus, Ph.D. Duke University Postdoctoral Fellow, Dept. of Invertebrate Zoology Advisor: Karen Osborn

Hyperiid amphipods are small crustacean invertebrates that are abundant from the surface down to the deepest depths of the oceans, with particular abundance in the twilight zone (200-1000 meters below the surface). At twilight-zone depths, available light is limited to increasingly dim and blue light and bioluminescence. In this zone it is a matter of life and death to see, but not be seen. As a result, hyperiids vary greatly in the shapes and function of their eyes, likely an evolutionary response to the complexities of the midwater optical environment. Generally, hyperiids have two pairs of apposition compound eyes, a dorsal set and a lateral set. In some hyperiids the dorsal eyes are greatly enlarged and cover the entire head. In others fiber optic cables connect the lenses to the retinas, or they have cone shaped retinas that allow a 360° field of view. Still others have retinas with mirrors that boost light collection. I will study the visual adaptations of hyperiids to life in the deep sea by examining the shape, physiology, and behavior of various species spanning the depth distribution of the group. I will then model the optical habitat and visual capabilities of hyperiids to examine the advantages of various visual adaptations. I will also map features of the visual system onto a recently completed reconstruction of the evolutionary history of hyperiids to track adaptations to the different optical environments they experience.

Tyler Lyson, Ph.D. Yale University Postdoctoral Fellow, Dept. of Vertebrate Zoology Advisors: Kevin de Queiroz, George Zug

I am interested in addressing two major questions during my postdoctoral fellowship: how do turtles breathe, and to which other group of vertebrates are they most closely related - lizards, turtles, birds, crocodiles, or mammals? Both questions have dogged scientists for centuries. To determine the evolutionary position of turtles in the vertebrate tree of life I will gather and integrate data on development and adult form (from both extinct and living species), as well as on genetics of living species. Placing turtles on the evolutionary tree will resolve one of the last big mysteries in the high-level relationships among major groups of terrestrial vertebrates. I will address the question of how turtles breathe by dissecting the lungs and associated musculature of several turtle species. Turtles have locked up their ribs

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in the shell and unlike other amniotes are not able to use their ribcage to expand and contract their lungs. Instead they use highly derived abdominal muscles. My dissections will help determine the evolutionary steps necessary for turtles to change from breathing with rib-based muscles, as in their earliest ancestors, to breathing with abdominal muscles.

Graham Slater, Ph.D. University of California at Los Angeles Postdoctoral Fellow, Dept. of Paleobiology Advisors: Gene Hunt, Kristof Helgen (Dept. of Vertebrate Zoology)

Understanding the processes that generated the diversity of animal life we see today remains one of the great challenges of evolutionary biology. Traditionally, paleobiologists have inferred patterns and rates of evolution by examining change in the form of animals in the fossil record. Evolutionary biologists, on the other hand, tend to infer evolution from the relationships among living species alone. I will use an approach that combines evidence from both the fossil record and relationships among living species to study the evolution of diet and locomotion in members of the dog family, Canidae. Dogs are an ideal group for such a study because they are ecologically diverse, possess an excellent fossil record, and for most of their evolutionary history they were confined to North America. In the course of my three-year Peter Buck fellowship I will produce a complete family tree for all living and fossil dogs and determine the age of each split in geological time. I will then investigate how the diets of dogs have evolved over the past 45 million years and test whether canids evolved running "pursuit predation" gradually over time in an arms race with their prey, or more suddenly, in response to climate and environmental change. In addition to providing new insights into the evolution canids, my research will provide a novel and significant integration of methods for studying evolution using fossils and living species.

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Maya Yamato, Ph.D. Massachusetts Institute of Technology/Woods Hole Oceanographic Institute Postdoctoral Fellow, Dept. of Vertebrate Zoology Advisors: Kristof Helgen, Nicholas Pyenson (Dept. of Paleobiology)

Despite widespread concerns about the effects of anthropogenic noise on baleen whales, we lack basic knowledge about their auditory physiology that we need to build and validate risk assessments. Hearing ranges and sensitivities could be measured if customized equipment and methods were developed based on how baleen whales hear. However, sound reception pathways and hearing mechanisms in baleen whales are currently unknown. With support from the Peter Buck Fellowship, I will examine the auditory anatomy of various fresh and preserved baleen whale specimens to understand how their ears function. I am also interested in studying the Smithsonian's collection of fossil marine mammals to learn about the evolution of underwater hearing.

Reuven Yeshurun, Ph.D. University of Haifa, Israel Postdoctoral Fellow, Dept. of Anthropology Advisor: Melinda Zeder

I am going to study the fossil animal remains from several archaeological sites in the Nile Valley, dating from 15,000- 10,000 thousand years ago. This timeframe is extremely important in human evolution, since it is when nomadic hunter- gatherers commenced the transition to settled life and plant cultivation, forming the earliest complex societies. Animal remains from these archaeological sites will yield information on human hunting, subsistence, and ecology. My research will shed light on an under-studied region of the Near East during an important period, improving our knowledge of prehistoric developments in adjacent regions.

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Peter Buck Fellows, Class of 2011

Fellowship Fellow University Research Project Advisors Term

Dr. Richard S. Barclay, Northwestern University A Geologic Analogue for Modern CO2 Scott Wing January Dept. of Paleobiology Increase: Reconstructing Atmospheric 2012 – CO2 through the Paleocene-Eocene January Thermal Maximum 2015 Dr. Michael Branstetter, University of California Davis Phylogeny, biogeography and life Ted Schultz May 2012 – Dept. of Entomology history evolution in ants: Insights from March 2014 Stenammini (Hymenoptera: Sean Brady Formicidae: Myrmicinae) Dr. Emily Goble, Yale University Miocene and Pliocene East African Richard Potts September Human Origins Program Fauna Relative to Global Climate 2011 – Change. Matthew Tocheri September 2013 Dr. Brent Grocholski, Massachusetts Institute of The Lower Mantle and the Earth’s Elizabeth Cottrell September Dept. of Mineral Technology Water Cycle 2011 – Sciences Jeffrey Post August 2014

Dr. Eliécer Gutiérrez , City University of New York Revealing the Evolutionary History of Kristof Helgen May 2012 – Dept. of Vertebrate the Deer Genus Odocoileus, with March 2015 Zoology (Mammals) Emphasis on the Cariacou Complex Jesus McDonald (Research Geneticist, Smithsonian Conservation Biology Institute) Dr. Alison Hamilton, University of California Los Evolutionary Diversification of a Kevin de Queiroz September Dept. of Vertebrate Angeles Radiation of Tree Skinks in the 2011 – Zoology (Amphibians Isolated Islands of Oceana. George Zug September and Reptiles) 2013

Nathan Andrew Jud, PhD candidate, University of The Angiosperm Invasion of North Scott Wing June 2011 – Dept. of Paleobiology Maryland College Park America: Quantitative Analysis of the May 2013 Rise of Flowering Plants William DiMichele

Jeffrey Sosa-Calvo, PhD candidate at the Revision of the Non-Leaf-Cutting Ted Schultz August 2011 Dept. of Entomology University of Maryland Fungus-Farming Ant Genus – August Myrmicocrypta Fr. Smith (Formicidae: Sean Brady 2013 Attini), with Morphological and Molecular Phylogenetic Analyses of Ants and Fungal Cultivars Dr. Daniel Thomas, University of Cape Town Diet and Feather Color of Fossil Birds Helen James (Curator in January Dept. of Paleobiology Using Raman Spectroscopy Charge, Birds) 2012 – January Matthew Carrano 2014 (Curator of Dinosauria) Dr. Bert Van Bocxlaer, Ghent University Patterns of Diversification in an Ellen Strong April 2012 – Dept. of Invertebrate Endemic Clade of Freshwater Snails in March 2014 Zoology the East African Rift Lake Malawi Gene Hunt, Paleobiology

Dr. Anne Wiley, Dept. Michigan State University Variation in Individual Feeding Habits Helen James July 2011 – of Vertebrate Zoology Through Time and Space: Gauging the July 2013 Sensitivity of Seabirds to Changes in Prey Availability

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Peter Buck Fellows, Class of 2012

Fellow University Research Project Advisors

Dr. Bonnie Blaimer, University of California at Patterns and Processes of Phylogenetic Ted Schultz Dept. of Entomology Davis Community Structure in Ants Across Four Habitat Types in Madagascar Sean Brady

Dr. Sara Casado-Zapico, University of Oviedo, Spain Age Estimation by Measurement of Doug Ubelaker Dept. of Anthropology Oxidative Stress in Teeth from Different Populations. Comparison with Classical Methods Dr. Frederick Davis, University of Minnesota First-row Transition Elements in Elizabeth Cottrell Dept. of Mineral Oceanic Island Basalts and Upper Sciences Mantle Lithologies

Dr. Torsten Dikow, Cornell University / American Taxonomy and Phylogeny of Norm Woodley (USDA) Dept. of Entomology Museum of Natural History Leptogastrinae Robber Flies (Insecta: Diptera: Asilidae) Sean Brady

Dr. Jamie Fergus, Duke University Visual Adaptations to the Deep Water Karen Osborn Dept. of Invertebrate Column in Hyperiid Amphipods. Zoology

Dr. Tyler Lyson, Yale University Kevin de Queiroz Dept. of Vertebrate Zoology George Zug

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Dr. Graham Slater, University of California at Tempo and Mode of Gene Hunt Dept. of Paleobiology Los Angeles Ecomorphological Diversification in Canidae: A Phylogenetic and Kristof Helgen (Dept. of Paleobiological Perspective Vertebrate Zoology) Dr. Maya Yamato, Massachusetts Institute of Sound Reception in Baleen Whales: Kristof Helgen, Dept. of Vertebrate Technology/Woods Hole Applying New Techniques and Fresh Zoology Oceanographic Institute Perspectives to a Longstanding Nicholas Pyenson (Dept. Question of Paleobiology) Dr. Reuven Yeshurun, University of Haifa, Israel Late Paleolithic Taphonomy and Melinda Zeder Dept. of Anthropology Subsistence in the Nile Valley: The Archaeofaunas of the Kom Ombo Plain and Wadi Halfa

Note: The start and end dates for the 2012 fellows are still tentative, so they are not included in this report.

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