The fossils document the explosion of new life over the first million years after the Cretaceous-Paleogene mass extinction.
Chew, mash, crunch, grind... oh, the things we do with our teeth! AAAS Fellow Peter Ungar finds teeth facinating, "the product of half a billion years of evolution." Ungar is a paleoanthropologist and evolutionary biologist at the University of Arkansas. Ungar studies the tooth shape and patterns of use-wear (microscopic scratches and pits that form on a tooth's surface as the result of its use) on a wide varity of animals, apes and primates, dinosaurs and Neandertals, and our own distant ancestors.
In his recently published book, Teeth: A Very Short Introduction, Ungar provides insight into the origins of human and mammalian teeth. He looks at tooth size, shape, structure, wear and makeup to chart their development, and shows how recent changes to human diet are now affecting dental health. Ungar also demonstrates how fossil teeth are helping to fill in important gaps in the paleontological record.
Listen to Ungar read selections from the book.
The frosty highlands of the Tibetan Plateau may have been an evolutionary cradle for woolly rhinos and other shaggy, cold-hardy creatures that roamed North America and Eurasia during the last Ice Age, according to a new study in Science.
The 2 September report describes fossils from an ancient species of woolly rhino that was roaming the Zanda Basin on the Tibetan Plateau 3.7 million years ago, sweeping snow out of its way with an elongated face and massive nasal horn.
Two partial skeletons unearthed from a cave in South Africa belong to a previously unclassified species of hominid that is shedding new light on the evolution of our own species, Homo sapiens, researchers say. The newly documented species, called Australopithecus sediba, was an upright walker that shared many physical traits with the earliest known Homo species—and its introduction into the fossil record might answer some key questions about what it means to be human.