A comprehensive analysis of thousands of fossils collected during the Great Depression in Texas revealed a remarkable diversity of ancient species. With its gomphotheras, rhinos, antelopes and elephant-like camels, the Lone Star State was once a place very similar to the Serengeti.
Between 1939 and 1941, the United States Works Administration (WPA) funded the Statewide Paleontological-Mineralogical Survey, an innovative program that recruits unemployed Texans for fossil collecting. So many fossils have been collected during these three years that scientists have not yet gone through the entire collection held at the University of Texas at Austin.
Recently, Steven May, a palaeontologist from the UT Jackson School of Geosciences, has sorted bones, teeth and various tusks on sites near Beeville, Texas. The results of this work, published this week in the scientific journal Palaeontologia Electronica, show an incredible diversity of animals from the past of the region – a true "Texas Serengeti", described in an associated press release.
This collection of Era Depression, however, was prone to a pretty interesting selection effect – the result of the collectors themselves. The fossils came almost exclusively from larger animals. Collectors were not formally trained in paleontology and they naturally selected the most remarkable and exciting fossils they could find, such as large tusks, teeth and skull. The tiny mouse bones, for example, have been largely ignored. Aware of this, May returned to the original site to compensate for these omissions. The new document therefore contains specimens collected more than 80 years ago, as well as those of its own recent efforts.
In total, May discovered 4,000 distinct specimens, representing 50 animal species. These animals lived along the Gulf of Texas coast between 11 and 12 million years ago in a mixed environment of forests and grasslands including a vast flood plain and winding rivers. The comparison with the current African Serengeti is therefore quite relevant. The animals described in the new study include rhinos, alligators, antelopes, camels, dozens of different horses and several species of carnivores.
May's research also includes undocumented animals in the area, including a brand new kind of gomphothere – a distant parent of elephants with a shovel-shaped lower jaw. The new animal is now named Blancotherium buckneri.
Of the 50 vertebrate species described in the new study, five are fish, seven are reptiles, two are birds and 36 are mammals. Of the 36 mammals, four are rodents, five carnivores (including an extinct parent of modern dogs), two proboscidians, even-fingered ungulates, and ungulate-fingered ungulates. The research also uncovered the oldest American alligator fossil ever discovered.
This work is still far from complete and many bones collected at other sites in Texas during these years have not yet been studied. More is almost coming.[Palaeontologia Electronica]