| Services |
|
|
|
|
 |
|
| News |
|
|
|
|
|
|
|
|
|
| Channels |
| Home & Family |
|
|
|
|
|
|
|
| Leisure |
|
|
|
|
| Technology |
|
|
|
|
|
| Business |
|
|
|
|
| Science |
|
|
|
|
|
|
|
|
|
|
Site Search  |
|
|
|
|
| Free email |
|
|
|
|
 |
Traces evolution of extinct sabertooths and the American cheetah-like cat |
| TheallIneed.com/NC&T/Cell |
The work is reported in the August 9 issue of Current Biology by Ross Barnett of the University of Oxford and a team of researchers from Britain, Canada, the United States, Sweden, and Australia.
Toward the end of the last Ice Age, around 13,000 years ago, North and South America were home to a variety of large cats such as the sabertooths (Smilodon and Homotherium) and other now-extinct species known as the American lion-like cat (Panthera atrox) and cheetah-like cat (Miracinonyx trumani). Of these big cats, only the puma (Puma concolor) and jaguar (Panthera onca) survive in the Americas today.
The evolutionary history of the extinct American cats has been closely studied by palaeontologists, but it has been difficult to determine the exact relationships of several groups. In the work reported this week, researchers created an updated family tree for the ancient cats by comparing ancient DNA extracted from the preserved bones of the two sabertooths (a Smilodon specimen from Patagonia and a Homotherium specimen from the Yukon region) and the American cheetah-like cat (a Miracinonyx specimen from the state of Wyoming) with DNA from modern felid (cat-family) and carnivore species. The analysis shows that the sabertooth cats were a sister group to the modern cats--that is, they diverged early on from the ancestors of modern cats and are not closely related to any living felid species.
The phylogenetic tree drawn from the new data also shows that the American cheetah-like cat is genetically most closely related to the puma, rather than to the true African cheetah (Acinonyx jubatus). Miracinonyx and the true cheetah Acinonyx show remarkable morphological similarity, including elongated limbs and enlarged nares, but the genetic data indicate that this similarity is in fact a marvellous example of evolutionary parallelism, the development of similar body plans in response to similar ecological pressures. In light of the new DNA data and fossil information from other studies, it appears likely that a puma-like ancestor that migrated to the New World may have given rise to Miracinonyx and ancestral Puma a few million years ago, around the time that the North American prairie is thought to have undergone expansion.
|
| About the Author |
©2005 All rights reserved
|
|
|
| Quotes | I will not expose the ignorance of the faculty. - Bart Simpson.
I want an Internet. Can I have one of those? -- Spice Girl Mel B.,aka Scary Spice, pointing to a monitor during an AOL press conference
I want to get a tatoo of myself on my entire body, only 2 taller. -- Steven Wright
I think you should defend to the death their right to march, and then go down and meet them with baseball bats.-Woody Allen, on the KKK
|
| Writers | | If you are a writer and want to see your article published at Theallineed.com, just click here to submit. |
|
Myanmar: UN agency moves ahead with assessing how to help cyclone-impacted children
Highest and Best Use Analysis