This timeline of tyrannosaur research is a chronological listing of events in the history of paleontology focused on the tyrannosaurs, a group of predatory theropod dinosaurs that began as small, long-armed bird-like creatures with elaborate cranial ornamentation but achieved apex predator status during the Late Cretaceous as their arms shrank and body size expanded. Although formally trained scientists did not begin to study tyrannosaur fossils until the mid-19th century, these remains may have been discovered by Native Americans and interpreted through a mythological lens. The Montana Crow tradition about thunder birds with two claws on their feet may have been inspired by isolated tyrannosaurid forelimbs found locally. Other legends possibly inspired by tyrannosaur remains include Cheyenne stories about a mythical creature called the Ahke, and Delaware stories about smoking the bones of ancient monsters to have wishes granted. Tyrannosaur remains were among the first dinosaur fossils collected in the United States. The first of these was named Deinodon horridus by Joseph Leidy. However, as this species was based only on teeth the name would fall into disuse. Soon after, Edward Drinker Cope described Laelaps aquilunguis from a partial skeleton in New Jersey. Its discovery heralded the realization that carnivorous dinosaurs were bipeds, unlike the lizardlike megalosaurs sculpted for the Crystal Palace. Laelaps was also among the first dinosaurs to be portrayed artistically as a vigorous, active animal, presaging the dinosaur renaissance by decades. Later in the century, Cope's hated rival Othniel Charles Marsh would discover that the name Laelaps had already been given to a parasitic mite, and would rename the dinosaur Dryptosaurus. Early in the 20th century, Tyrannosaurus itself was discovered by Barnum Brown and named by Henry Fairfield Osborn, who would recognize it as a representative of a distinct family of dinosaurs he called the Tyrannosauridae. Tyrannosaur taxonomy would be controversial for many decades afterward. One controversy centered around the use of the name Tyrannosauridae for this family, as the name "Deinodontidae" had already been proposed. The name Tyrannosauridae came out victorious following arguments put forth by Dale Russell in 1970. The other major controversy regarding tyrannosaur taxonomy was the family's evolutionary relationships. Early in the history of paleontology, it was assumed that the large carnivorous dinosaurs were all part of one evolutionary lineage ("carnosaurs"), while the small carnivorous dinosaurs were part of a separate lineage (coelurosaurs). Tyrannosaurid anatomy led some early researchers like Matthew, Brown, and Huene, to cast doubt on the validity of this division. However, the traditional carnosaur-coelurosaur division persisted until the early 1990s, when the application of cladistics to tyrannosaur systematics confirmed the doubts of early workers and found tyrannosaurs to be large-bodied coelurosaurs. Another debate about tyrannosaurs would not be settled until the early 21st century: their diet. Early researchers were so overwhelmed by the massive bulk of Tyrannosaurus that some, like Lawrence Lambe, were skeptical that it was even capable of hunting down live prey and assumed that it lived as a scavenger. This view continued to be advocated into the 1990s by Jack Horner but was shown false by Kenneth Carpenter, who reported the discovery of a partially healed tyrannosaur bite wound on an Edmontosaurus annectens tail vertebra, proving that T. rex at least sometimes pursued living victims.
Prescientific
The Delaware people of what is now New Jersey or Pennsylvania had a tradition regarding a hunting party that returned with a piece of an ancient bone supposedly belonging to a monster that killed humans. One of the village's wise men instructed people to burn bits of the bone in clay spoons with tobacco and make a wish while the concoction was still smoking. This ritual could bestow such favors as success in hunting, long life, and health for one's children. This tale might be inspired by local fossils, which include Dryptosaurus, ankylosaurs, Coelosaurus, and Hadrosaurus. The Cheyenne believed that a mythical creature called an Ahke once lived in the prairies of the western United States. These creatures were thought to resemble giant buffalo, whose bones turned to stone. Ahke bones were found both on land as well as buried in the banks of streams. Tyrannosaurus fossils preserved in Hell Creek Formation strata may have been influences on this old legend. Its contemporary Triceratops is another possible influence, as well as the more recent Cenozoic fossils of Titanotherium and mastodons.
19th century
1850s
1856 Joseph Leidy described the new genus and species Deinodon horridus.
1860s
1865 Leidy described the new genus and species Tomodon horrificus.
1866 Edward Drinker Cope described the new genus and species Laelaps aquilunguis. This discovery proved that theropod dinosaurs walked on their hind limbs rather than on all fours like in earlier reconstructions. He also erected the family Deinodontidae.
1868 Leidy described the new genus and species Aublysodon mirandus. Leidy described the new genus Diplotomodon for the species Tomodon horrificus. Cope described the new species Laelaps macropus.
1870s
1876 Cope described the new species Laelaps incrassatus and Laelaps falculus. He also described Aublysodon lateralis. Cope described the new species Laelaps hazenianus.
1877 Othniel Charles Marsh described the new genus Dryptosaurus to house the species Laelaps aquilunguis.
1880s
1884 Joseph Burr Tyrrell discovered a partial Albertosaurus skull near Kneehills Creek in Alberta, Canada. This specimen is now catalogued as CMN 5600.
1890s
1890 Marsh described the new species Ornithomimus grandis.
1892 Cope described the new genus and species Manospondylus gigas. Marsh described the new species Aublysodon amplus and A. cristatus. Oliver Perry Hay described the new species Dryptosaurus kenabakides.
20th century
1900s
1900 Barnum Brown found a partial skeleton of Tyrannosaurus in eastern Wyoming.
1902 Barnum Brown found a substantially complete skeleton of Tyrannosaurus in the Hell Creek Formation of Montana.
… excerpt ends here. Continue reading the full article.
