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
In the year 2006 paleontologists will celebrate the 150th
anniversary of the first description of a dinosaur fossil from North
America. In March 1856 Joseph Leidy of Philadelphia wrote a brief
paper describing and naming four kinds of 75-million-year-old
reptilian teeth that had been discovered the previous year in the
Cretaceous beds of the Judith River region of Montana. Without any
of the media hoopla that accompanies many dinosaur discoveries
today, he showed that two of the new reptiles were unquestionably
dinosaurs, as judged from comparison with discoveries made in
England 30 years before. These were the first American dinosaurs.
(Leidy thought that the other two came from
"lacertilians"—lizards—but they eventually
turned out to be dinosaurs too.) Or perhaps they weren't. Who gets
credit for the first North American dinosaur is a matter that
depends on what constitutes a description, what counts as a fossil
and whether its collector or describer knew what he had, and when.
1824: Early English Dinosaurs
The first ever description of a dinosaur fossil had been by Robert
Plot, first director of the Ashmolean Museum at Oxford in his
Natural History of Oxford-shire of 1677. It was the
distal end of a femur and had been found in the village of Cornwell
in Oxfordshire. Plot gave an excellent drawing of the bone, but
identified it as the thigh bone of a human giant. (Every
paleontology student also knows that in 1772, the naturalist Richard
Brookes turned Plot's figure upside down and, noting a startling
resemblance to male genitalia, gave it its first formal name:
Scrotum humanum. Probably because of this notoriety,
the original specimen has long since disappeared.)
In 1824 William Buckland at Oxford, describing a suite of fossils
from the nearby village of Stonesfield, gave Plot's creature the
name Megalosaurus. Enough of it was preserved to show that
Megalosaurus was a flesh-eating reptile some 40 feet long.
Buckland's publication was the first modern, scientific description
of dinosaur remains, even though he, not unreasonably, thought it
was a giant lizard; the discrete category "dinosaur" was
only defined by the British zoologist Richard Owen, first director
of the Natural History Museum in London, in 1842.
Buckland had been obtaining Megalosaurus material from
private collectors for at least a decade, and the existence and
nature of his fossils were already well known in the scientific
community. Unsure what the creature was, Buckland was finally pushed
into publishing by the great French zoologist and paleontologist
Georges Cuvier, who wanted to include the Oxfordshire monster in a
new edition of his grand compendium Recherches sur les Ossemens
Fossiles des Quadrupedes (1824).
Because of his vacillations, Buckland almost missed being first into
print with a dinosaur (after Plot, that is). The accomplished
amateur paleontologist Gideon Mantell had been busy collecting in
the Tilgate Forest region of Sussex and had already mentioned his
finds in his book Fossils of the South Downs (1822) as
"the teeth, vertebrae, bones, and other remains of an animal of
the lizard tribe of enormous magnitude." The same fossils were
noted in The Gentleman's Magazine in 1823, and Cuvier
included a reference to the teeth in his Ossemens Fossiles.
But even Cuvier was not sure what Mantell's creature was; he thought
the teeth might have been from a fish but "it is not impossible
that they also came from a saurian, but a saurian even more
extraordinary than all that we now know." Unable to obtain the
imprimatur of Cuvier and perhaps due to Buckland's competitiveness,
Mantell could not get a formal paper published on his discovery
until early 1825. He identified his animal as a plant-eating reptile
and named it Iguanodon (because of the resemblance of its
teeth to those of a living iguana). Seven years later, Mantell
described his second dinosaur: Hylaeosaurus, a somewhat
smaller, spikey creature, also a herbivore.
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.
1836: The Footprints of "Giant Birds"
The reason that one might hesitate to record Leidy's fossils as the
first American dinosaurs is that, 20 years previously, the Reverend
Edward Hitchchock, president of Amherst College, had described
dinosaur trackways from the sandstone of the Connecticut River
Valley. Such foot prints had first been noticed in 1802 by a boy
named Pliny Moody on his father's farm at South Hadley,
Massachusetts. In early 1836, two local men found more tracks at a
quarry near Montague, Massachusetts, and drew them to the attention
of a doctor James Dean and the Reverend Hitchcock; the two later
squabbled about who had "first scientifically investigated and
described the fossil footmarks of the Connecticut valley."
The trackways that Hitchcock described in a long article in the
American Journal of Science in 1836 were of 11 kinds,
all made, he concluded, by giant three-toed birds that he termed
Ornithichnites. By 1858 Hitchcock, having scoured the pits
where the Late Triassic red sandstone was quarried for building and
"flagging" stones, had raised the total to 70. These
putatively included traces from marsupials, lizards, frogs,
chelonians (turtles) and invertebrates, as well as
"birds." In so doing, he founded the new science of
ichnology—the study of footprints.
The principal argument against recognizing Hitchcock as the first to
record North American dinosaur fossils is not that he thought they
had been made by birds, but that they were only impressions made by
dinosaurs, not bony, bodily remnants of dinosaurs. If a fossil is
anything "dug up" (Latin: fossilis), then
Hitchcock gets the palm, but only for the first "trace
fossils." For real fossil remains, Leidy is the winner.
1787: What Constitutes a Description?
But Leidy is still only the first by default. As early as 1787, the
Philadelphia merchant Timothy Matlack and the distinguished
physician and anatomist Caspar Wistar read before a meeting of the
American Philosophical Society an account of "A large thigh
bone found near Woodbury Creek in Glocester County, N.J." The
creek runs not far from where, 70 years later, the first associated
remains of any dinosaur were excavated and described by Leidy as
Hadrosaurus—another herbivore like
Iguanodon. The Minutes of the October 5, 1787 meeting of
the Society record only the subject of the presentation and the
admonition that the authors, with a Dr. John Rodgers, were "to
search for the missing part of the skeleton." Unfortunately, no
copy of their manuscript exists, nor is there any information about
whether further collecting was attempted. Even the specimen itself
is missing, but we can be reasonably sure that this femur was the
first discovery of an American dinosaur. It would be nice to think
that the bone still exists in someone's attic.