Behold the mighty dinosaur

65 Pages·2008·0.626 MB·English

by  John C Kricher, Recorded Books, Inc

B
EHOLD THE
M
IGHTY
D
INOSAUR
COURSE GUIDE
Professor John Kricher
WHEATONCOLLEGE
Behold the Mighty Dinosaur
Professor John Kricher
Wheaton College
RecordedBooks™isatrademarkof
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Behold the Mighty Dinosaur
Professor John Kricher
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Executive Producer
John J. Alexander
Executive Editor
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RECORDING
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COURSE GUIDE
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Lecture content ©2007 by John Kricher
Course guide ©2007 by Recorded Books, LLC
Cover image: © Crystal Brooks/shutterstock.com
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2007 by Recorded Books, LLC
#UT108 ISBN: 978-1-4281-7390-3
All beliefs and opinions expressed in this audio/video program and accompanying course guide
are those of the author and not of Recorded Books, LLC, or its employees.
Course Syllabus
Behold the Mighty Dinosaur
About Your Professor/Introduction...............................................................................4
Lecture 1 What Is (or Was) a Dinosaur?...............................................................6
Lecture 2 Digging Up Dinos...................................................................................9
Lecture 3 Dinosaurs Discovered..........................................................................12
Lecture 4 The Bone Wars....................................................................................16
Lecture 5 The Museum That Dinosaurs Built......................................................19
Lecture 6 Dinosaurs Enter Pop Culture...............................................................23
Lecture 7 Dinosaur Origins..................................................................................27
Lecture 8 In the Days of Dinosaurs.....................................................................31
Lecture 9 Dinosaur Diversity................................................................................35
Lecture 10 Dinosaurs Become Dynamic...............................................................39
Lecture 11 Dinosaurs Become Airborne................................................................43
Lecture 12 Dinosaurs as Living Animals...............................................................48
Lecture 13 T. REXDeconstructed and Reconstructed...........................................52
Lecture 14 The Cretaceous Extinction Event........................................................57
Course Materials........................................................................................................62
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About Your Professor
John Kricher
John Kricher is a professor of biology
at Wheaton College, Norton, Massachu-
setts. His books include Galapagos: A
Natural History,A Neotropical
Photo courtesy of John Kricher C(SaFEniooradsums tt PthpGewaarucnneiii dsfoFietcneo ,rtNronetoh sDFrrttesoihne;rw oe Reessocastscotu ;kl Froyasog .nM rydJe oo fsiCuhetsnanld)tl ,ia i fsgaoin unra nidad ifaneedsl-
low in the American Ornithologists
Union and past-president of both the Association of Field Ornithologists and
Wilson Ornithological Society. His interest in dinosaurs has taken him to vir-
tually all of the major museum collections and he has “hunted dinosaurs” in
Connecticut, Colorado, Utah, Wyoming, Montana, and along the Red Deer
River in Alberta. He teaches about dinosaurs in his classes and he has
amassed a large private collection of dinosaur models. He resides with his
wife Martha Vaughan on Cape Cod.
Introduction
Dinosaurs—the word means “fearfully great reptile”—have been a source of
fascination ever since their discovery in England early in the nineteenth cen-
tury. No human ever has or ever will see a live long-necked APATOSAURUS, the
odd-plated STEGOSAURUS, or the infamous TYRANNOSAURUSREX, yet common
birds such as cardinals and chickadees trace their ancestries back to
dinosaurs. Dinosaurs, once believed to be immense behemoths, dull of mind,
slow of body, mired in swamps like so many oversized sluggish lizards, have
reawakened interest, and research on dinosaurs has burgeoned.
Dinosaurs present the ultimate puzzle in forensic science. They excite our
curiosity, even our awe. Aside from birds, all dinosaurs have been extinct for
65 million years, yet, before then, they dominated Earth’s terrestrial habitats
for about 160 million years, far longer than primates, to say nothing of
humans, have been around. We have evidence of their existence and even
of their former lives, evidence in the form of bones, skulls, whole skeletons,
skin, trackways, eggs, nests, even feces. The puzzles about dinosaurs are
complex, but nonetheless we have learned a great deal about them, especial-
ly in the last fifty years. Our view of dinosaurs has changed radically, and the
evolution and biology of dinosaurs has become a popular topic in college cur-
riculums. This lecture series will explain how this changing view of dinosaurs
developed and what it means to evolutionary biology.
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Beginning with the discovery and initial interpretation of dinosaurs, we will
come to understand why these unique animals were initially thought to be
large lizards but were soon realized to be in a group of their own. We will
learn of the great finds of the late-nineteenth and early-twentieth centuries
and the infamous “bone wars” fought between two driven geniuses to estab-
lish supremacy as dinosaur collectors. We will follow the great dinosaur
collectors through the American West and on to Mongolia in search of
fossil bones. The American Museum of Natural History in New York City
now houses the greatest collection of dinosaur skeletons, largely because it
was recognized early in the twentieth century that dinosaurs interest the
public and people will come to museums to see their remains.
Since their discovery, dinosaurs have been part of pop culture. Books and
films have featured and celebrated dinosaurs. Professor Kricher will detail
how dinosaur pop culture has evolved, including the great interest generated
by the release of the film Jurassic Parkin 1993, soon followed by the highly
acclaimed BBC series Walking with Dinosaurs.
In the mid-1960s scientists began to view dinosaurs differently. Evidence
mounted, largely thanks to two paleontologists from Yale University, John
Ostrom and Robert Bakker, that dinosaurs were warm-blooded and active,
more like mammals and birds than like reptiles. At about the same time new
attention was given to the old notion that birds evolved from dinosaurs. Field
and lab studies burgeoned and Professor Kricher will discuss how the
“Dinosaur Renaissance” was achieved and how it resulted in a great rush of
new dinosaur exploration, excavation, research, and interpretation. Never
have dinosaurs been more a focus of science than they are today.
The lectures will explain evolutionary and ecological relationships among
dinosaurs and provide the listener with a sense of what it might have been
like to be present in the Mesozoic Era during the time of the dinosaurs. One
lecture will be devoted entirely to questions surrounding TYRANNOSAURUSREX
and the final lecture will deal with the question of what ultimately brought
about the total extinction of all of the non-bird dinosaurs.
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Lecture 1:
What Is (or Was) a Dinosaur?
The Suggested Readingfor this lecture is John Noble Wilford’sThe
Riddle of the Dinosaur.
poem written less than a century after the discovery of
dinosaurs begins with the line, “Behold the mighty dinosaur,
famous in prehistoric lore.” Dinosaurs, a name that trans-
lates to “fearfully great reptile” (sometimes interpreted as
“terrible lizard”), have excited the public mind ever since
their discovery in the early nineteenth century. They
have been portrayed as immense in size, bizarre in
appearance, stupid of mind, impressively dangerous,
and, of course, totally extinct. Indeed, the name
“dinosaur” is sometimes applied to anything or anyone perceived to have out-
lived its usefulness. Dinosaurs have become icons of failure, the poster chil-
dren for extinction. At the same time, they continue to fascinate. And thanks
to advances in computer animation, films such as Jurassic Parkand the BBC
series Walking with Dinosaursvirtually re-create these wondrous creatures of
the Mesozoic Era.
Were dinosaurs evolutionary failures? I say an emphatic “No!” and this lec-
ture series will hopefully convince you that dinosaurs were and, in the form of
birds, continue to be one of the most diverse and successful groups of back-
boned animals.
The poem The Riddle of the Dinosaurcaptures the mystique of these
remarkable animals. It is about a dinosaur named STEGOSAURUS, a creature
most children could identify. Bigger than the largest rhino, its back lined with
formidable bony plates, and a tail armed with four menacing bony spikes, this
animal is easily recognized. Add to that countenance its tiny head containing
a walnut-sized brain and you have the enigma of the dinosaur: large, bizarre,
stupid. STEGOSAURUShad a swelling in its vertebral column at its hips, indicat-
ing that its spinal cord was unusually thick in that region. This reality gave
rise to the fanciful notion that “the creature had two sets of brains,” the topic
of the poem.
Dinosaurs are among the only animals we know by their scientific rather
than common names. We don’t call it “roofed lizard,” we call it STEGOSAURUS.
We refer to ALLOSAURUSand ANATOTITAN, rather than “other lizard” and “big
duck.” Some dinosaurs have even been named more than once. The
dinosaur APATOSAURUS(meaning “deceptive lizard”) was once called
E BRONTOSAURUS, a great name that translates to “thunder lizard.” But, alas, a
ON bundle of bones was named APATOSAURUSbefore another bundle of bones
E from a different individual of the same species was named BRONTOSAURUS, so
R
U APATOSAURUSis the official scientific name. Perhaps the finest dinosaur name
CT of them all is TYRANNOSAURUSREX, the “king of tyrant lizards.”
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Many dinosaurs were large, even huge, bigger than any other land animals
to have ever existed. Some of the largest weighed in excess of fifty tons. But
many were comparable in size to some of today’s mammals, such as ele-
phants, rhinos, and hippos. Some were rather small and some only the size
of chickens, weighing less than house cats. Many were indeed bizarre in
appearance and certainly many would be dangerous were they still roaming
the wilds today. And, yes, many were dumb, even by crocodile standards.
But not all were.
Are dinosaurs extinct? Their time, the Mesozoic Era, ended abruptly sixty-
five million years ago. Gone were the likes of T. REXand TRICERATOPS, per-
haps done in by the effects of a ten-kilometer asteroid striking the Earth. But
as these lectures will make clear, birds evolved from a lineage of dinosaurs.
Birds survived the big extinction event and thus only the so-called “non-avian
dinosaurs” became extinct. One group of dinosaurs survived, the birds, and
today nearly ten thousand feathered dinosaurs, more than twice the number
of mammal species, share our world.
The Riddle of the Dinosaur
by Bert Leston Taylor
(1866—1921)
Behold the mighty dinosaur, Each thought filled just one spinal column.
Famous in prehistoric lore, If one brain found the pressure strong
Not only for his power and strength It passed a few ideas along.
But for his intellectual length. If something slipped his forward mind
You will observe by these remains ’Twas rescued by the one behind
The creature had two sets of brains— And if an error he was caught
One in his head (the usual place), He had a saving afterthought.
The other at his spinal base. As he thought twice before he spoke
Thus he could reason ‘A Priori’ He had no judgment to revoke.
As well as ‘A Posteriori.’ Thus he could think without congestion.
No problem bothered him a bit Upon both sides of the question.
He made a head and tail of it. Oh, gaze upon this model beast,
So wise was he, so wise Defunct ten million years
and solemn, at least.
© Clipart.com
Source: The Edgar Rice Burroughs Library; http://www.erbzine.com/dan/t1.html
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FOR GREATER UNDERSTANDING
Questions
1. Why are dinosaurs often viewed as “evolutionary failures”?
2. Why is this view not accurate?
Suggested Reading
Wilford, John Noble. The Riddle of the Dinosaur. New York: Alfred A.
Knopf, 1985.
Other Books of Interest
de Camp, L. Sprague, and Catherine Cook de Camp. The Day of the
Dinosaur. New York: Doubleday & Company, 1968.
Websites to Visit
The Dinosaur Corporation website Dinosaur Timeline Galleryfeatures a col-
lection of dinosaur and prehistoric illustrations by paleo-artist Josef Moravec
along with short overviews of the different periods in Earth’s history —
http://www.prehistory.com/colorchr.htm
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Lecture 2:
Digging Up Dinos
The Suggested Readingfor this lecture is John R. Horner’s
Digging Dinosaurs.
inosaurs first evolved in the Mesozoic Era about 230
million years ago and they did not become extinct until
sixty-five million years ago (and even then, they were
survived by the birds). So the non-avian dinosaurs
enjoyed a long tenure on Earth, about 165 million
years, far longer than humans or their immediate
ancestors have been present on the planet. That span
of time seems like a lot, ample time to accumulate many
dinosaur corpses. But it’s not that simple. The world is not lit-
tered with dead bodies of animals because they are scavenged, torn apart,
rotted, and totally decomposed, ultimately by bacteria. So it is now, so it was
in the days of dinosaurs.
Fossils are relatively rare. The chance of any animal becoming fossilized is
miniscule. The chances of hitting the fossil jackpot, becoming the one T. REX
that is perfectly preserved down to the last little bone, is likely less probable
than winning a huge lottery jackpot. But given lots of time and lots of
dinosaurs, there are winners. We have a fossil record to draw upon.
The fossil record is the dinosaur database. And excavating these long-dead
creatures and then reconstructing how they looked in life and how they lived
presents the ultimate in forensic science.
Like all creatures, dinosaurs died of illness and infection, predation, injury,
accidents, or, rarely, old age. When a dinosaur died it was likely to be con-
sumed by a predator or scavengers and they would scatter its bones. Rarely
are complete skeletons found. If the corpse was not immediately dismem-
bered it would bloat from intestinal bacterial gasses, maybe even rupture.
Many dinosaur remains are found with their necks arching well over their
backs, a posture called the “death pose.”
Hard parts such as teeth and bones tend to decompose slowly simply
because they are mostly mineral and thus not nutritious to decomposer
organisms. Teeth, particularly enamel, are the hardest part of a vertebrate
animal, because they comprise mostly minerals of phosphorus and calcium.
Soft parts are readily consumed and thus are rarely preserved.
Sometimes dinosaur skin, at least parts of it, are fossilized. In addition, such
things as dinosaur eggs and nests, tracks and trackways, and feces some-
times fossilize. All of these things are intensively studied.
An artifact must be at least ten thousand years old to be considered a fossil
and thus all dinosaur remains are fossils. In most cases the original bone has
been replaced by other minerals, the process called petrification. Dinosaur
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