Some fossil finds - Miocene Texas and vegetarian crocodilians

[lpetrich]

Ancient 'Texas Serengeti' had elephant-like animals, rhinos, alligators and more -- ScienceDaily

Now, decades after they were first collected, a UT researcher has studied and identified an extensive collection of fossils from dig sites near Beeville, Texas, and found that the fauna make up a veritable "Texas Serengeti" -- with specimens including elephant-like animals, rhinos, alligators, antelopes, camels, 12 types of horses and several species of carnivores. In total, the fossil trove contains nearly 4,000 specimens representing 50 animal species, all of which roamed the Texas Gulf Coast 11 million to 12 million years ago.

... They include a new genus of gomphothere, an extinct relative of elephants with a shovel-like lower jaw, and the oldest fossils of the American alligator and an extinct relative of modern dogs.

The Lapara Creek Fauna: Early Clarendonian of south Texas, USA
Plain-language abstract:

A large collection of fossil vertebrates from near Beeville, Texas, is known as the Lapara Creek Fauna. It was obtained by the State-Wide Paleontologic and Mineralogic Survey of Texas (1939–1941) under the direction of the Bureau of Economic Geology and the Texas Memorial Museum. Of the 50 species of fossil vertebrates, five species are fish, seven are reptiles, two are birds and 36 are mammals. The 36 species of mammals represent 31 genera of which four are rodents, five are carnivores, two are elephant-like forms, 10 are camel and antelope-like forms and 10 are horses and rhinos. These animals lived on the Texas coastal plain about 10–12 million years ago, and their remains were preserved in the Goliad Formation. The fauna includes very early occurrences of certain turtles, an alligator and a dog-like carnivore. One of the elephant-like animals represents a new genus named Blancotherium. The geology of the Goliad Formation and the composition of the Lapara Creek Fauna indicate that the environment in this part of Texas 10–12 million years ago was a mixed woodland–grassland with broad floodplains and meandering rivers

 

[lpetrich]

Some ancient crocodiles may have chomped on plants instead of meat | Science News noting Repeated Evolution of Herbivorous Crocodyliforms during the Age of Dinosaurs: Current Biology

An analysis of fossil teeth suggests that plant-eating relatives of modern crocodiles evolved at least three times during the Mesozoic Era, which stretched from roughly 252 million to about 66 million years ago, researchers report June 27 in Current Biology.

Today’s crocodiles are predominantly carnivorous, and have the simple, conical chompers typical of meat eaters. But in the teeth of their relatives of yore, “there is this tremendous diversity … that we don’t see today,” says study coauthor Keegan Melstrom, a paleontologist at the University of Utah and Natural History Museum of Utah, both in Salt Lake City.

Several other such transitions are known, herbivores being much like some carnivorous or omnivorous ancestors.

 Therizinosauria of the Cretaceous were theropods, relatives of tyrannosaurs and birds. But they were mainly plant eaters.

In the present, giant pandas are bears that eat mostly bamboo, and grass carp eat aquatic plants.

Taking a longer view, it is likely that *every* herbivorous vertebrate has ancestors that were carnivorous or omnivorous if one looks far back enough.