MARGINALIA
American Dinosaurs: Who and What Was First
Who gets credit for the first dinosaur in North America depends on one's definition of a description and a fossil
Keith Thomson
1856: The "First" American Dinosaur
As soon as Joseph Leidy received the Judith River fossils, he
naturally compared them directly with the known European forms. From
their teeth, the carnivorous form, Deinodon (now
Albertosaurus), appeared to be the equivalent of
Megalosaurus, and the herbivore Trachodon, with
leaf-shaped teeth, was clearly similar to Iguanodon.
Leidy, termed by his biographer Leonard Warren "the last man
who knew everything," was a Philadelphia physician who had
several careers in parallel: teacher, researcher, anatomist,
microscopist, protozoologist, parasitologist (he discovered the
nematode causing trichinosis) and—after the urging of the
great British geologist Charles Lyell—a paleontologist. His
first paper on fossil vertebrates established the existence of
ancient horses in North America prior to their extinction sometime
in the past two million years. The following year he received the
first of a trickle—soon to become a flood—of new
discoveries of fossil vertebrates from the "Bad Lands"
(mauvaises terres a travailler, as French trappers had
put it) of the White River region of what is now South Dakota.
Leidy did not venture out west himself until 1872. For 25 years, he
worked on specimens either sent to him by collectors or discovered
by the remarkable explorer, surveyor and paleontologist Ferdinand
Vandiveer Hayden, who was then right at the beginning of a
distinguished and contentious career. Hayden graduated in 1850 from
Oberlin College in Ohio and briefly taught school before getting a
medical degree at Albany Medical College in Albany, New York. When
the brilliant (if cantankerous) geologist James Hall, the state
geologist for New York, decided that he wanted to send an expedition
out to the White River Bad Lands, he chose two men to go: his
assistant Fielding Bradford Meek (a specialist in invertebrates) and
Hayden. This trip was the beginning of a longstanding, classic
collaboration, out of which came much of our understanding of the
stratigraphy and paleontology of the Upper Missouri region.
Hayden's fossils from the 1853 expedition sponsored by Hall found
their way to Leidy to describe. From that time, although lacking any
prospect of further employment, Hayden was sure of his vocation. In
letters to Spencer Baird, assistant secretary of the new Smithsonian
Institution, he wrote: "I could endure cheerfully any amount of
toil, hardship, and self denial ... to labour in the field as a
naturalist. I could live as the wild Indian lives ... without a
murmur …. My love for natural History is so great that I
hardly feel any disposition for anything else."
Hayden cast about for sponsors for a second trip. He offered
to collect for Leidy and the Philadelphia Academy of Natural
Sciences, but they were too cautious. Finally, he settled for this
second-best choice: two years of collecting for Colonel Alfred
Vaughn, the Indian Agent at St. Louis, with the fossils to be split
between them. This time Hayden traveled through much of the Upper
Missouri country either alone or with men from the American Fur
Company. When they saw what he had brought back, Leidy and the
Academy turned out to be willing to pay for his fossils because
included in that collection were the teeth that he had picked up
from near the confluence of the Judith River and the Missouri.
» Post Comment