Word: fossils
(lookup in dictionary)
(lookup stats)
Dates: during 2000-2009
Sort By: most recent first
(reverse)
...little more than two centuries ago, with the Industrial Revolution. Using the new technology of the steam engine in the early 19th century, and the internal combustion engine in the century just ended, society found itself able to exploit on a massive scale the energy locked in such fossil fuels as coal, oil and gas. At the same time, dramatic gains in agricultural productivity made possible by mechanized farming, fertilizers and more efficient water use pushed people from farms into factories and cities. The net result was a revolution in living standards that the world had never seen or even...
Finding Toumai Man, the oldest hominid, in Chad [PALEONTOLOGY, July 22] fits in well with the theory of punctuated equilibrium developed by paleontologists Niles Eldridge and Stephen Jay Gould. [The theory explains why new species, rather than evolving gradually over millions of years, seem to suddenly appear in the fossil record, punctuating long periods of species stability, or equilibrium.] The Toumai fossil could have been a member of a peripherally isolated community that evolved into our oldest ancestors. You reported that several modern-looking hominids coexisted, and this also jibes with the introduction of members of an isolated community into...
Although the Chad fossil find is indeed important, as a paleontologist I can assure you I am not scrambling to digest its implications. The traits that Toumai exhibits are what may be expected in a 7 million-year-old ape inhabiting woodlands whose origin predates the human-African ape divergence. The fossil record is far too complete for any one single ape fossil to jar the expectations of any serious paleontologist. ESTEBAN E. SARMIENTO Department of Vertebrate Biology American Museum of Natural History New York City...
That puts the new Sahelanthropus tchadensis at a crucial evolutionary crossroads. Scientists have long believed that apes and humans share a common ancestor. But recently, comparisons of fossil and modern primates and analyses of modern ape and modern human DNA have independently indicated that a single ancestral ape gave rise to both chimps and hominids between 5 million and 7 million years ago. That presumed great-great-great-grandape almost certainly swung from trees in the African forest. If so, then Sahelanthropus, or Toumai, could well have been the very first hominid, or at least one of the first...
...wrong evolutionary tree after all. At least one equally eminent paleontologist, Tim White of the University of California, Berkeley, disputes the assertion that Toumai derails the standard evolutionary family tree, let alone plants a bush in its place. The discovery is a tremendous accomplishment, he says. "This fossil is the closest we've got to the common ancestor. But dentally, it's just like Ardipithecus, except for a few minor characteristics." The mix of primitive and more advanced traits leaves him similarly unimpressed, since such mixing has been seen in various species discovered over the past 80 years. In spite...