Protoavis
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Protoavis texensis (The "first bird from Texas") is (controversially) regarded as an extinct species that could be the earliest fossil of a bird, pushing back avian origins into the Late Triassic.
Protoavis is claimed to have been a foot-tall bird that lived in what is now Texas, USA, around 225 million years ago. Though it existed 75 million years earlier than Archaeopteryx its skeletal structure is unexpectedly more bird-like. Protoavis has been reconstructed as carnivorous bird that had teeth on the tip of its jaws and eyes located at the front of the skull, suggesting that it may have hunted at twilight or in the dark. It had little flying ability but could probably have flown up a tree.
However, this description of Protoavis assumes that Protoavis actually existed and, if so, that it has been reconstructed correctly. Many biologists doubt Protoavis because of the circumstances of its discovery. When they were discovered at a quarry in the Texas panhandle in 1984, in sedimentary strata of a Triassic river delta, the fossils were a jumbled cache of disarticulated individuals that may reflect an incident of mass mortality following a flash flood. The discoverer, Sankar Chatterjee of Texas Tech University, was convinced that the cache of crushed bones all belonged to the same species. However, only a few parts were found, primarily a skull, and this has led many to believe that the Protavis fossil is chimeric, made up of more than one organism.
If it really existed, Protoavis would raise interesting questions about when birds began to diverge from the dinosaurs, but until better evidence is produced, the animal's status currently remains uncertain.
External link
- Protoavis reconstruction (http://www.bsu.edu/web/00cyfisher/Protoavis.htm)
- More detailed information from EvoWiki: The Protoavis controversy (http://wiki.cotch.net/wiki.phtml?title=The_Protoavis_controversy)