This is a recent article on historical paleontology by Dr. Keith Thompson,
formerly of the Philadelphia Academy of Natural Sciences and the Oxford
Museum of Natural History. (and the upcoming April DVPS Speaker) - Patti
Kane-Vanni
Published in American Scientist:
Vist http://www.americanscientist.org/template/AssetDetail/assetid/50776
to view the article with illustrations
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 Stewart 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.
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Copyright (c) 2003, Sigma Xi