Geoscience Reference
In-Depth Information
miles south of Buenos Aires, hired another famous fossil collector
named Santiago Roth. Roth was a Swiss scientist interested in
dinosaurs and fossil mammals, as well as the geology of Patagonia.
Over three decades, Roth and other scientists made important col-
lections of dinosaurs and other fossils that comprised the ancient
fauna around Neuquen.
Over the next century, dinosaur fossils were discovered in several
parts of Argentina. These fossils dated from throughout the Mesozoic
era—an interval of geologic time often called the Age of Large
Dinosaurs. The Mesozoic is divided into three periods. The Triassic
period extended from about 250 million years ago to about 206 mil-
lion years ago. The Jurassic period began at the end of the Triassic and
concluded about 144 million years ago. The final period, called the
Cretaceous, extended from 144 million years ago to 65 million years
ago.
In 1884, bones that Roth had discovered were sent to Richard
Lydekker, a famous British paleontologist. The scientific study of
dinosaurs was in its incipient stages, even though their fossils had
been collected for centuries and had probably inspired the creation of
numerous mythological creatures, such as the griffin. In scientific
terms, dinosaurs had first been recognized as ancient reptiles, in
England, during the 1820s. By the 1880s, few skeletons of dinosaurs
had been discovered, collected, and studied. Nonetheless, Lydekker
identified the remains Roth had found as belonging to titanosaurs,
long-necked, giant, plant-eating dinosaurs belonging to the group
called sauropods. Lydekker noticed the remarkable similarity between
these Patagonian dinosaur bones and others found in 70-million-
year-old rocks from India, which belonged to a titanosaur that he had
named
Titanosaurus indicus,
which means "Indian
Titanosaurus."
He thought that the Patagonian species and the Indian species were
closely related, and thus he christened the Patagonian species with a
new name,
Titanosaurus australis,
which means "southern
Titanosaurus."
Later studies have shown that the bones identified by
Lydekker were not so closely related to the Indian titanosaur, but
instead belonged to a quite different and older titanosaur from the
80-million-year-old, Cretaceous rock unit called the Rio Colorado
Formation. This is the same rock unit that produced the fossils that
we discovered more than a century later.
