Credit: Andrew Gillis
Ted Daeschler is a vice president of Philadelphia's Academy of Natural Sciences and an associate professor in the Department of Biodiversity, Earth and Environmental Science at Drexel University. His research interests involve vertebrate fossils of the late Devonian period (385 million to 363 million years ago) and the origin of limbed vertebrates. He has done considerable fieldwork among rocks of the Devonian period in Pennsylvania and the Canadian Arctic, including high above the Arctic Circle in the Nunavut Territory. His team's discoveries include the description of the 375-million-year-old Tiktaalik roseae, widely recognized as the evolutionary link between fish and limbed animals. At the Academy of Natural Sciences, his responsibilities encompass research, collections building and public programs — including work on a general-audience website called "Devonian Times," which won a Scientific American Science and Technology Web Award in 2005. Daeschler earned his Ph.D. in geology at the University of Pennsylvania.
Credit: Chris Green
Jennifer Clack is a professor at the University of Cambridge and the curator of vertebrate paleontology at the university's Museum of Zoology. She studies fish and early land-living vertebrates, with a focus on the timing and sequence of the fish-tetrapod transition. The author of Gaining Ground: The Origin and Early Evolution of Tetrapods, she was involved in the discovery in East Greenland of the remains of two tetrapods from the Devonian period — Acanthostega and Ichthyostega. Her current work centers on the earliest Carboniferous-period tetrapods. She was awarded the Daniel Giraud Elliot medal by the U.S. National Academy of Sciences, the T. Neville George Medal by the Glasgow Geological Society and an honorary D.Sc. by the University of Chicago. She's also a Fellow of the Royal Society and a foreign honorary member of the American Academy of Arts and Sciences. She holds a Ph.D. from the University of Newcastle upon Tyne.
Clifford Tabin is the Leder Professor of Genetics and chair of the Department of Genetics at Harvard Medical School, where he's been on the faculty since 1989. His lab, which studies the genetic basis of shape and pattern formation, was responsible for the first use of retroviral vectors for gene transfer into developing chick embryos — opening that system for genetic manipulation. Among his many findings are contributions to the understanding of limb development and discovery of the first genes involved in regulating left-right asymmetry in the embryo. He has also studied the evolution of diverse species, including finches in the Galápagos and blind cavefish. He's been awarded numerous prizes, including the Society for Developmental Biology's Conklin Medal and the March of Dimes Prize in Developmental Biology. A member of the National Academy of Sciences, he earned his Ph.D. in biology at the Massachusetts Institute of Technology.
Randall Dahn studied limb growth and development at the University of Wisconsin-Madison, completing his Ph.D. there in 2003. His focus was on understanding the molecular cues that pattern a limb — for instance, identifying which genes determine the difference between a thumb and a pinkie. He went on to do postdoctoral work in organismal biology with Neil Shubin at the University of Chicago, investigating how evolution has had an impact on these molecular pathways — preserving some and altering others, to produce the stunning diversity of limbs and fins evident in the world today. He currently resides in Madison, Wisconsin.
Credit: Steve Tolan
Roger Smith has headed the Karoo Paleontology Department at Iziko South African Museum since 1990. A native of Cambridge, England, he emigrated to South Africa in 1976. After working for several years on diamond exploration, he earned his Ph.D. in geology at the University of Cape Town. He now oversees numerous research projects concerning the paleoecology of Gondwana, an ancient Southern Hemisphere supercontinent. His specialty is reconstructing primeval landscapes of the Karoo Basin in South Africa. Recently, he has focused on determining how the End-Permian mass extinction, 252 million years ago, affected vertebrate communities in southern and western Gondwana. Over the past 10 years, he's participated in collaborative expeditions to Eritrea, Niger, Tanzania, Zambia, Lesotho, Namibia, Madagascar, Patagonia, Brazil and Antarctica. This has allowed him to extend his search for fossilized Karoo faunas into the peripheral rift valleys and to track ancient migration corridors across the global supercontinent of Pangaea.
Credit: Tathyane Teshima
Abigail Tucker is a member of the Departments of Craniofacial Development and Stem Cell Biology and of Orthodontics at King's College London. She specializes in the embryonic development of the head. Her lab focuses on the formation of the ear, nose, glands and teeth, to understand how these complex organs are shaped and what goes wrong in cases of birth defects. Her current work involves the formation of the middle ear and the ways that defects in the process can affect hearing and susceptibility to middle-ear disease. She also studies how the structures of the head have changed during the evolution of vertebrates, using developmental biology to identify the mechanisms behind such changes and to understand the effects of humans' evolutionary past on our current health. Tucker holds a D.Phil. in the biological sciences from Oxford University.
Karen Sears is an assistant professor at the University of Illinois' School of Integrative Biology and Institute for Genomic Biology. Her research involves the developmental mechanisms that have influenced mammals' morphological diversification, or the way their form and structure have changed over time. Specifically, she seeks to understand how development has been modified to generate new morphologies and the role that development plays in influencing why certain morphologies rather than others evolve, sometimes repeatedly. To address these questions, she combines traditional embryological and paleontological approaches with modern developmental and genetic techniques to gather data from fossilized and living mammals. Her lab works with opossums, bats, horses, pigs and mice. Her work was featured in "Extreme Mammals," a national touring exhibit organized by the American Museum of Natural History. She earned her Ph.D. in evolutionary biology at the University of Chicago.
Credit: David Christopher
Zhe-Xi Luo is a professor of organismal biology and anatomy at the University of Chicago. He seeks to better understand the origin and evolution of mammals by studying mammal fossils of the Mesozoic era — the age of dinosaurs. In his quest for the world's earliest known placentals, marsupials and other ancient mammals, he's conducted fieldwork in many parts of the United States and China. Luo's goal is to shed light on mammalian evolutionary relationships, functional adaptations, ecological diversification and developmental patterns. A former curator of paleontology at the Carnegie Museum of Natural History, he is also committed to fostering public understanding of science. He's the recipient of a National Science Foundation CAREER Award and of the Humboldt Award for Senior Scientists from the Alexander von Humboldt Foundation in Germany. After completing his undergraduate education in China, Luo earned his Ph.D. in paleontology at the University of California, Berkeley.
Credit: Jeff Gage/Florida Museum of Natural History
Jonathan Bloch, the associate curator of vertebrate paleontology at the Florida Museum of Natural History, also holds adjunct appointments in zoology, anthropology and the geological sciences at the University of Florida. He studies fossilized vertebrates from the Cenozoic era, with a focus on the first appearance and early evolution of modern orders of mammals, including primates. His field research has taken him from Cenozoic deposits in Wyoming and Montana to the Cerrejón and Bogotá formations of northern Colombia to exposures along the Panama Canal. A former associate editor of the Journal of Human Evolution, Bloch is currently coeditor of Paleobiology and a member of the editorial board of the Journal of Mammalian Evolution. He earned his Ph.D. in geological sciences at the University of Michigan.
Credit: Katie Neitz
Jay Neitz, the Bishop Professor of Ophthalmology at the University of Washington, studies the biological basis of color vision and vision defects. Neitz's lab has discovered the role played by genetic mutations in many common vision problems that affect modern humans. He's used colorblindness in primates as a model to explore the potential for gene therapy to cure vision problems in humans — work that was ranked by Time magazine as one of the top 10 scientific discoveries of 2009. He's successfully added a third type of cone pigment to dichromatic retinas by using a viral vector for gene transfer therapy. And he's shown that new visual capacities can arise from the addition of a single therapeutic gene in adults — demonstrating the potential for genes to cure adult vision disorders. He earned his Ph.D. in biopsychology at the University of California, Santa Barbara.
Donald Johanson is the founding director of the Institute of Human Origins and also holds the Virginia M. Ullman Chair in Human Origins in the School of Human Evolution and Social Change at Arizona State University. For more than 30 years, he has conducted field and laboratory paleoanthropology research. Most notably, he discovered the 3.2-million-year-old hominid skeleton known as "Lucy." He is an honorary board member of the Explorers Club, a Fellow of the Royal Geographical Society, and the recipient of various international prizes. He's written numerous scientific and popular articles and several books, including, with Maitland Edey, Lucy: The Beginnings of Humankind (1981), a best-seller and winner of the National Book Award in Science. In 1994, he narrated a NOVA series seen by more than 100 million viewers. His latest book is Lucy's Legacy (2009), with Kate Wong. He earned his Ph.D. in anthropology at the University of Chicago.
Credit: Cesur Pehlevan
Tim White is a professor of integrative biology at the University of California, Berkeley, where he also heads the Human Evolution Research Center. With colleagues from Ethiopia and the Los Alamos National Laboratory, he codirects the Middle Awash Project in Ethiopia's Afar Basin, and he was a speaker in a four-part lecture series — Bones, Stones, and Genes: The Origin of Modern Humans — where he described some of that project's findings. His own research involves the evolution and function of early hominids' skeletal structure. The Middle Awash research team's most celebrated find to date is "Ardi," an Ardipithecus ramidus fossil that was covered widely in both print and broadcast media and that earned White a spot on Time's 2010 list of the 100 "people who most affect our world." A member of the National Academy of Sciences, White earned his Ph.D. in biological anthropology at the University of Michigan.
Credit: Jeff Glidden
Owen Lovejoy is a professor of anthropology at Kent State University and holds adjunct appointments in anatomy at Northeast Ohio Medical University and in orthopedics at the University of Pittsburgh Medical School. He also chairs the anthropology section of the National Academy of Sciences, to which he was elected in 2007, and serves on the editorial board of the Proceedings of the National Academy of Sciences. He has published widely on varying issues in human evolution, with a focus on early hominids' locomotion and social behavior. His work includes reconstruction of parts of the 3.2-million-year-old fossil known as "Lucy" and of a 4.4-million-year-old species known as "Ardi." He's currently analyzing "Kadanuumuu," a 3.6-million-year-old partial skeleton that provides further insight into the evolution of hominids. He earned his Ph.D. in biological anthropology at the University of Massachusetts, Amherst.
Credit: Susan Griffith
Bruce Latimer is the founding director of Case Western Reserve University's Center for Human Origins and a professor of orthodontics at Case's School of Dental Medicine. He also holds adjunct appointments in anthropology, anatomy and cognitive science and is a founding fellow of Case's Institute for the Science of Origins. He was previously executive director of the Cleveland Museum of Natural History. His research involves the comparative anatomy and biomechanics of primates, particularly the origin of humans' ability to walk upright, and has been published in Nature, Science and other influential journals. He has been involved with many prominent paleoanthropology projects, from analyzing the Australopithecus afarensis fossil known as "Lucy" to describing a new species of early hominid, Ardipithecus ramidus. He is currently codirecting excavations at the recently discovered Manot Cave in Israel. Latimer earned his Ph.D. in biomedical science at Kent State University.
Credit: Arizona State Univesity
William Kimbel is the director of Arizona State University's Institute of Human Origins and the Virginia M. Ullman Professor of Natural History and the Environment in the ASU School of Human Evolution and Social Change. He conducts field, laboratory and theoretical research in paleoanthropology, with a primary focus on hominid evolution in Africa during the Pliocene and Pleistocene epochs. His work has taken him from the famous excavations at Hadar in Ethiopia to Olduvai Gorge in Tanzania, as well as to Kenya, South Africa and Tunisia. He has also collaborated with Israeli colleagues on excavations of Middle Paleolithic Neanderthal remains from the Amud Cave, near the Sea of Galilee. Kimbel earned his Ph.D. at Kent State University and was an editor of the Journal of Human Evolution from 2003 to 2008. He is a fellow of the American Association for the Advancement of Science.
Thomas Burbacher is a professor of environmental and occupational health sciences at the University of Washington (UW). In addition, he directs the Infant Primate Research Laboratory, a core facility supported by both UW's National Primate Research Center and its Center on Human Development and Disability, and heads the Primate Research Center's Division of Reproductive and Developmental Sciences. He teaches classes in basic environmental and occupational health, as well as children's environmental health, and he has served on advisory panels for the Environmental Protection Agency, the Food and Drug Administration and the National Academy of Sciences. His research involves environmental influences on brain development in primates, with a focus on changes in brain development and function caused by prenatal exposure to neurotoxicants. He holds a Ph.D. in developmental psychology from the University of Washington.
Susan Spieker is a professor of family and child nursing at the University of Washington (UW) School of Nursing, as well as the director of the Barnard Center for Infant Mental Health and Development, which is jointly sponsored by UW's School of Nursing and its Center on Human Development and Disability. Her research focuses on the role of parent-infant relationships in children's social and emotional development and learning. She and her colleagues develop and test longitudinal prevention and intervention programs aimed at promoting secure relationships and social and emotional well-being for infants and children — especially those in high-risk, vulnerable populations. She earned her Ph.D. in developmental psychology at Cornell University.
Peter Holland is the Linacre Professor and head of the Department of Zoology at the University of Oxford. For more than 25 years, he's conducted research on animal diversity, with a particular focus on the evolution of embryonic development. He looks at the interplay among genes, embryos and evolution in a variety of animal models — including mammals, insects, fish and a wormlike creature called amphioxus. Holland is a Fellow of the Royal Society and has received many international prizes, including the Genetics Society Medal, the De Snoo van 't Hoogerhuys Medal, the Scientific Medal of the Zoological Society of London, the Linnean Medal for Zoology and the Kowalevsky Medal. He is the author of The Animal Kingdom: A Very Short Introduction, published in 2011 by Oxford University Press, which offers an overview of animal evolution for students of science and nonscientists alike. He earned his Ph.D. in genetics at the University of London.
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