Word: fossilizing
(lookup in dictionary)
(lookup stats)
Dates: during 1990-1999
Sort By: most recent first
(reverse)
...study, based on a new analysis of fossil sites, has created a tempest in the paleontological community. Now researchers not only must explain how a single prehuman population could remain frozen in evolutionary amber for so long after its species went extinct elsewhere in the world, but also must revisit two of science's most hotly debated questions: Where on the habitable continents did modern humans first emerge, and how did they come to dominate the world? "These dates will stir up a lot of controversy," says geochronologist Carl Swisher of the Berkeley Geochronology Center in Berkeley, California, who headed...
...while the new discovery brings paleontologists closer to solving the mystery of Homo's origin, it still falls frustratingly short. Although the scientists found a nearly complete upper jaw, 10 teeth and a number of tooth fragments, they can't say for certain which species the fossil belongs to. By 1.9 million years ago, the Homo line had spawned at least two branches: Homo habilis and Homo rudolfensis. The new fossil resembles both species in some ways, but without a more nearly complete skull it's impossible to say more. "What we have now is a hypothetical human lineage with...
Then two veteran fossil hunters from the local Afar tribe, exploring near a dry stream bed, spotted something out of place: two pieces of a prehistoric upper jaw that had eroded from a hillside. "The instant we fit the jaw together," says William Kimbel, science director of the Institute of Human Origins in Berkeley, California, and a leader of the expedition, "we knew we weren't dealing with an apelike Australopithecus [the scientific name for Lucy...
...fact, as the researchers explain in a report that will appear in the December Journal of Human Evolution, the jaw belonged to the genus Homo, the line that includes modern Homo sapiens. The fossil has been dated at 2.33 million years old--arguably the oldest Homo fossil ever found, and right in the middle of the mystery zone. What's more, the bones were found near stone tools of the same age--the oldest combination of bones and artifacts ever discovered...
...about 2.7 million years ago and transformed much of Africa's moist woodlands into dryer, more open savannah. Was the development of tools and a more upright stance an evolutionary strategy to cope with the rigors of the new environment? Perhaps. But until now nobody had found a Homo fossil that dated back anywhere near 2.7 million years...