Whatever
Happened to the Brontosaurus?
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 The
Brontosaurus as Marsh envisioned him: wrong head,
wrong name, wrong lifestyle. (Copyright
Lee Krystek, 2002.)
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There was a time when the dinosaur named Brontosaurus
evoked images of a monstrous beast with four legs, a long, graceful
neck dragging an even longer tail through primeval swamps. The
meaning of the name, "Thunder Lizard," seemed perfect
for an animal who must have shook the ground with every step
he took. Thousands of children knew this dinosaur by that name.
It even appeared as the symbol of a major oil company and starred
as one of four ancient, extinct reptiles featured on U.S. postal
stamps.
In the last 20 years, however, this name has disappeared
from books and museum exhibits about dinosaurs. Whatever happened
to this famous beast?
The Brontosaurus, a member of a family of
dinosaurs that walked on four legs with long necks and long
tails called sauropods, was the victim of a war that
was played out over a hundred years ago. Starting in the late
1860's, two of America's most prominent paleontologists, Edward
Drinker Cope and Othniel Charles Marsh, had a falling out. Cope
claimed that Marsh had paid quarrymen in New Jersey to divert
fossils they found for him to Marsh. Personal attacks between
the men, thinly veiled as "scientific criticism,"
followed in articles that they wrote for publication. Later,
each would send teams into the fossil fields of the West where
they would fight over digging rights amid claims that the other
side had destroyed or damaged fossils in order to block their
rivals from getting a hold of them.
One outgrowth of these "bone wars" was
an unscientific competition between Cope and Marsh to see who
could discover the most species of extinct beasts. In their
rush to beat each other to the next find, the scientists often
based their claims on incomplete or inaccurate data.
In 1877 Marsh wrote a short two-paragraph article
for the American Journal of Science. The article, entitled
"Notice of New Dinosaurian Reptiles from the Jurassic Formation,"
didn't have illustrations and included only a description of
the animal's vertebral column, but he named the creature anyway.
Marsh estimated that the Apatosaurus, meaning "deceptive
lizard", was fifty feet in length. Marsh followed this
article with another one in 1879 where he showed a sketch of
the creature's pelvis, shoulder blade and vertebrae.
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Othniel
Charles Marsh
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In that same year, in another short article in American Journal
of Science, Marsh claimed finding another dinosaur based on
a description of the pelvis and vertebrae. He named this one Brontosaurus
and estimated it to be seventy to eighty feet in length.
The Brontosaurus soon went on to become one
of the most famous dinosaur species of all time. A nearly complete
skeleton found by Marsh was mounted in Yale's Peabody Museum.
There it captured the public's imagination as did a beautiful
illustration Marsh published in The Sixteenth Annual Report
of the US Geological Survey, 1895. The Yale skeleton was
the first sauropod dinosaur put on display anywhere in the world
when it was mounted in 1905 and the animal was clearly labeled
as a "Brontosaurus."
In contrast the few unspectacular Apatosaurus
bones Marsh found were never augmented with a full skeleton.
Iin his rush to beat Cope, Marsh had made a mistake,
however. The Apatosaurus was not a separate species,
but simply a juvenile example of Brontosaurus. In 1903
Elmer Riggs of the Field Museum in Chicago was studying Marsh's
work when he found this mistake:
...the writer is convinced that the Apatosaur
specimen is merely a young animal of the form represented in
the adult by the Brontosaur specimen.
Riggs, following the naming rules for animals that
applied at the time added:
...In view of these facts the two genera may
be regarded as synonymous. As the term"Apatosaurus"
has priority, "Brontosaurus" will be regarded as a
synonym.
Despite the poor Brontosaurus losing its official
status very early in the 20th century, the name continued to
be used in popular books, semi-technical articles and even on
museum displays. The Brontosaurus became the symbol for Sinclair,
a petroleum supplier, and a full-sized model made its appearance
at the oil company's exhibit at the 1964-65 New York World's
Fair.
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A
rare, souvenir Brontosaurus model from the Sinclair
exhibit at the 1964-65 World's Fair.
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The question of the popular Brontosaurus
name verses the technically-correct Apatosaurus name
came to a head in 1989 when the U.S. Post Office decided to
release a set of four stamps illustrating "dinosaurs."
One in the series was a picture of a large sauropod labeled
Brontosaurus. This upset some dinosaur enthusiasts who
accused the Postal Service of promoting scientific illiteracy,
an ironic accusation given the number of museums that had the
animal mislabeled for decades. While there was a hue and cry
over the Brontosaurus name, few even mentioned the other, more
glaring error, which was the inclusion of a Pteranodon (a flying
reptile) in a set of dinosaur stamps. By definition dinosaurs
do not have wings.
A few prominent people came to the defense of the
Brontosaurus and the Postal Service. Stephen Jay Gould,
the noted biologist, pointed out that the issue was a tempest
in a teapot in his famous article, "Bully for the Brontosaurus"
written for Natural History magazine. Robert Bakker,
the celebrated paleontologist and curator of the Tate Museum
in Casper, Wyoming, also continues to use the popular Brontosaurus
label instead of Apatosaurus.
To add insult to injury, the poor Brontosaurus not
only got a name change, but it was discovered that he had the
wrong head, too. One item that was not found in the excavation
with Marsh's Yale skeleton was a skull. Marsh mounted a head
found at a different location to complete the exhibit. For many
years scientists suspected that Marsh had gotten the wrong skull,
but it wasn't until 1970 that two scientists, John McIntosh
from Wesleyan University and David Berman of the Carnegie Museum,
proved it. The head that Marsh had mounted was from another
sauropod named Camarasaurus. The proper Brontosaurus/Apatosaurus
skull actually had a slightly longer snout and looked a
lot like the skull of another sauropod called Diplodocus.
Marsh's Brontosaurus would wind up getting
both his name and his head changed, but it is essentially still
the same animal. It it wrong to refer to an Apatosaurus
as the Brontosaurus? Not really. The popular synonym
has been around for many years and its meaning, "Thunder
Lizard," is highly descriptive to the sound the animal
made. What sense does the name "deceptive lizard"
make? How deceptive can a 70-foot long, 30-ton animal be?
Much more important than the question of names is
what we know about how the animal actually lived. Today, scientist's
vision of the habits and habitat of the Apatosaurus are
quite different than what Marsh and other early paleontologists
had thought. Early analysis suggested that the animals must
have been weak because their small heads could only chew the
minimum amount of food necessary to fuel such a big body. So
weak, in fact, that large sauropods were thought to be slow,
unable to lift their bulky tails off the ground and only able
to support their massive weight by living in shallow lakes and
swamps where water floated their bulk.
Paleontologists like Bakker showed that this image
was wrong. No Apatosaurus skeleton has been found in
an ancient body of water and its feet were not at all suited
for walking through marshy and muddy ground. In fact, Bakker
notes in his book Dinosaur Heresies, an analysis of changes
in geology over time suggest that large sauropods moved out
of areas as they became wet: they didn't like swamps at all.
Also, a careful reconstruction of the tail shows that it was
probably held aloft and could be swung back and forth, perhaps
for defense. The sauropod's small head was not a limit on how
much it could eat because the animals didn't chew their food
in their mouth. Like many modern birds (and crocodiles), they
ground up food in a lower part of the stomach called the gizzard.
Researchers have recovered stones from sauropod excavations
that the animals swallowed and that lay in the gizzard to aid
in the the grinding process. Because of this Bakker has suggested
these huge animals may have been so active that they could stand
on their rear legs to reach high plants or engage in mating
battles.
So, even if the poor Brontosaurus's name
was a casualty of the "bone wars," at least
we now have his lifestyle right.
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The
Brontosaurus/Apatosaurus liked dry floodplains,
not swamps, as once thought. (Copyright
Lee Krystek, 2002.)

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A
Partial Bibliography
Bully
for the Brontosaurus by Stephen Jay Gould, W.W. Norton &
Company, 1991.
The
Dinosaur Heresies by Robert T. Bakker, Willaim Morrow and
Company, Inc. 1986.
The
Ultimate Dinosaurs, Parragon Books.
2000.
Copyright Lee Krystek 2002. All
Rights Reserved.