Although fossil vertebrate remains were reported from Austin County, Texas, more than a century ago, these and other fossils obtained over the next four decades seemed to be of little more than local interest. However, the Lower Permian (Paleozoic) fossil fishes, amphibians, and reptiles discovered in north central Texas by Jacob Boll around 1870 attracted worldwide attention because of their bizarre appearance and diversity. Darwin's Origin of Species had appeared in 1859, and the controversy it engendered was raging. Dinosaurs had only recently been discovered, and O. C. Marsh's Dinosaurs of North America (1896) brought them to public attention. Among the Texas fossils then recovered were skeletons of Seymouria, a yard-long, heavy-bodied creature of lizard-like appearance. Seymouria has features of both amphibians and reptiles and was considered a link between these two vertebrate classes. Its exact position in the animal kingdom is still debated, but it is usually considered more amphibian than reptile. Boll collected these fossils for Edward D. Cope, Philadelphia Academy of Science, from 1877 to 1880. After Boll's death, Cope employed William F. Cummins, an itinerant preacher and geologist, to collect Permian fossils for him from 1880 to 1884. A professional collector, C. H. Sternburg, collected in the Lower Permian in 1882 for the Harvard Museum of Comparative Zoology; in 1895 and 1897 he worked for E. D. Cope and in 1901 for the Royal (Paleontological) Museum of Munich. Beginning in the early 1900s, E. C. Case collected in the Lower Permian of Texas for the University of Michigan and the University of Chicago. E. C. Olson, of the University of California at Los Angeles, worked intensively with the Permian vertebrates or north central Texas beginning in 1939. Many other paleontologists have collected and described Permian vertebrates, but the leading student of Texas Permian vertebrates was A. S. Romer, of Harvard University, who studied and reported on fossils from north central Texas from 1936 until his death in 1973. The field remains very active today. Wann Langston, Jr., and his students at the University of Texas at Austin have made important contributions. Numerous skulls, skeletons, and other bones of amphibians and reptiles, previously known only from fragments, have led to correction of some long-held but incorrect concepts. Most of the scientists who have worked with Texas Permian vertebrates during the last forty years have resided outside of Texas.
Mesozoic vertebrates of Texas have received less attention than Paleozoic. In the early 1900s E. C. Case collected and reported amphibians and reptiles found in Triassic sediments along the eastern edge of the High Plains, and Sankar Chatterjee of Texas Tech University has also made important discoveries there. Notable are skeletons of phytosaurs. These aquatic reptiles, up to thirty feet in length, had elongated snouts armed with thick, sharply pointed teeth. Their habits were probably much like those of modern crocodiles. Some lightly armored forms were not unlike crocodiles in appearance, except for their long, hook-nosed snouts, but some armored types of phytosaurs may have looked almost like arthropods. Through work centered at the University of Texas at Austin, parts of the Trans-Pecos region have yielded important fossils of Cretaceous reptiles, among them enormous crocodiles and the largest known pterosaur. Much of Central Texas probably contains bones of Cretaceous vertebrates, but the land is so heavily vegetated that discoveries are few. However, remains of dinosaurs, plesiosaurs, and even primitive mammals have been found and are preserved at the University of Texas and Southern Methodist University. Fossil vertebrates, especially mammals, of the middle to late Tertiary and Pleistocene ages abound in Texas. Much of the fossil history of horses, camels, rhinoceroses, and other kinds of both living and long-extinct mammals is represented in Texas Tertiary and Pleistocene rocks. Remains of fossil mammals probably occur in almost every county in the state. Familiar forms include mastodons, rhinoceroses, camels, horses, ground sloths, and saber-toothed tigers, but of equal interest are small mammals such as rats, mice, shrews, bats, and squirrels.
In the winter of 1899–1901 W. F. Cummins, who had earlier worked for Cope in the Permian, was employed by the newly formed Geological Survey of Texas. He found mammalian fossils in the late Tertiary Blanco Beds of Crosby County, Texas. E. D. Cope described these and other fossils recovered by Cummins between 1891 and 1893, thus calling attention to the rich deposits of late Tertiary vertebrates of the Texas Panhandle. The American Museum of Natural History sent expeditions directed by J. W. Gidley to the Panhandle during 1899, 1900, and 1901, and Gidley made large collections of mammals. In the 1920s and 1930s the University of California made several expeditions, directed by R. A. Stirton, to collect mammals in Hemphill and Donley counties. From the 1930s to the 1960s professional collectors working for the Childs Frick Laboratory of New York City collected mammals from a number of sites in the Panhandle, as did workers for West Texas State University in Canyon. In the late 1930s attention turned to the Tertiary vertebrates of the Texas Coastal Plain, with collections largely stored at the University of Texas. Beginning in the late 1960s J. A. Wilson, of the University of Texas, made significant discoveries of Tertiary mammals in rocks of the Trans-Pecos region. Probably the most important of these is the skull of a primitive, monkey-like primate that seems to be intermediate between the lemurs and the monkey group that now lives in South America. Rodents, carnivores, rhinoceroses, and other kinds of mammals, some with no close surviving relatives, have been discovered. Work in this area continues at the University of Texas. Most of the fossil-yielding deposits of Texas that date from 10,000 to perhaps 3,000,000 B.P. are of limited area, a few square miles or even yards. Each deposit, whether from a cave, terrace, floodplain, or ancient lake bed, was deposited during a relatively short time. Mammal fossils discovered in such sediments represent the fauna existing at that place at that particular time. Modern techniques of collecting and studying fossils permit the interpretation of climate, ecology, changes in distribution, evolutionary changes, and other details. The correlation of the innumerable deposits of this type, with modern methods of dating, will eventually fill in the history of Texas during the last few million years. Work of this kind is in progress at most institutions that support the study of vertebrate paleontology in Texas.
Individuals and institutions especially active in collecting and reporting the results of vertebrate paleontological studies in the mid-1980s included (from north to south) Gerald E. Schultz, West Texas State University, Canyon; Sankar Chatterjee, Texas Tech University, Lubbock; Walter W. Dalquest, Midwestern State University, Wichita Falls; Bob Slaughter and Lewis Jacobs, Southern Methodist University, Dallas; Arthur H. Harris, University of Texas at El Paso; and Wann Langston, Jr., John A. Wilson, and Ernest L. Lundelius, Jr., University of Texas at Austin.