Posts Tagged ‘fossils’

Monkeys in Texas

November 1, 2008

Well, not monkeys per se.  A dramatic fossil find by paleontologists from Duke Univesity reveals that primates persisted in Texas longer than anyone thought, untl at least 43 million years ago.

That long ago, of course, Texas was covered by tropical forest and active volcanoes.  Nowadays, the climate has cooled and the tropical biome is gone, so most would say that the native primates are extinct there, but I would disagree.   Just look at the Texas School Board.

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Most primitive tetrapod found

June 26, 2008

Today’s edition of Nature carries an article describing the most primitive tetrapod (four-legged creature) ever discovered. The creature, thought to have lived 365 million years ago, is ten years younger than the infamous Tiktaalik, but while Tiktaalik is thought to have more characteristics of fish than of tetrapods, the new discovery is thought to be a true tetrapod.

Some interesting notes:

The creature, named Ventastega curonica, is not the oldest tetrapod ever discovered, but it is the most primitive. This means that its features are more similar to fish (the ancestors of all land animals) than any other known tetrapod. This seems out of sequence with the usual trend in the fossil record, where more primitive animals are found in older rocks, and more complex creatures are found in newer ones. Because of this, the study’s lead author, Per Ahlberg, does not think that Ventastega is an ancestor of modern tetrapods, but rather an evolutionary branch that died out sometime in the past. That would have made it something of an evolutionary holdover in its time, somewhat like horseshoe crabs and egg-laying mammals today.

At the site in Latvia, no legs were found, but researchers were able to deduce that Ventastega had four legs through the shape of the pelvis and of other joints. Parts of the skull, shoulders and pelvis were all that was turned up.

Ventastega was probably three to four feet in length, and probably ate fish. It probably lived in shallow water, where its legs allowed it to move more efficiently than fins would have done. (Scientists say “probably” a lot.)

I love stories like this! Let’s hope paleontologists keep unearthing these key bits of the story of life.