DINOSAURIAN OSTEOLOGY: Lecture 1

1. HOW DINOSAUR BONES LOOK IN THE FIELD
2. MAMMALIAN GIANTS, THE ERA OF ELEPHANTS
3. DEVELOPMENT OF THOUGHT
4. VESTIGES OF REPTILIAN GIANTS
5. THE BEGINNING OF THE DINOSAURIAN ERA

I. HOW DINOSAUR BONES LOOK IN THE FIELD

1. Fossil bones
• isolated bones (usually water-worn) much more common than skeletal fragments
• crushed, permeated with quartz or carbonate, shattered by pressure off-loading, rain and frost, rock pressure, geothermal gradient
• shallowly buried bones can be beautifully preserved
• gypsum really messes up bone, especially in the Sahara
• usually distorted/fractured/crushed - very heavy and very weak
• wet bone extremely weak
• pristine, modern-looking bone seldom found - but exist
• isolated bones usually limb elements (often difficult to identify below family level)
• dinosaur teeth are usually difficult to identify (carnivores, ornithopods) converse in mammals
2. Indications of bones (counterintuitive - dinosaur bone in small pieces)
• small pieces, with angular breaks
• mollusc shell and dinosaur egg
• does not stick to tongue (recent bone does)
• seldom white (except in Asian dune deposits)
• usually disintegrates at the surface (looking for small pieces leads to discovery of skeletons)
• look for rivulets of bone chips
• bushes (plants) often grow on skeletal remains, roots invade bone (phosphorus)
• crushed and to some degree collapsed by rock pressure

 

 

Fluvial deposits usual matrix (stratum thickness)
Lake deposits are great - splitting slabs
Dune deposits can be sterile or very rich

3. What is also found:

 

 

More than half of fragments are not identified to a family group by field paleontologists. No-one has commented on differences in regional abundances of dinosaur-age scrap.

Jurassic-Early Cretaceous of China:

• turtle shell fragments
• theropod teeth (medium-sized, isolated, broken)
• pieces of large bone (broken, relatively unabraded)
• skeletons
Middle Cretaceous of Morocco:
• gar-like scales, large
• croc and theropod teeth, all sizes
• isolated crocodile and theropod verts, all sizes
Late Cretaceous dunes of the Mongolias:
• dinosaur eggs and articulated skeletons of small dinosaurs (isolated bones uncommon)
Late Cretaceous of the Western Interior of North America:
• gar scales, small theropod teeth
• scutes from small crocodiles
• shell fragments of small turtles
• fragments of ossified tendon (mostly from hadrosaurs)
• large clasts of weathered bone

 

 

Isolated foot bones (particularly those of small theropods) hold up well - at least as diagnostic as isolated teeth

Late Cretaceous of the southeastern US:
• shell fragments and bones of large turtles
• teeth and bones of large crocodiles
• rare, eroded vertebrae of large ornithopods
• a few teeth of small dinosaurs
4. The elusive dinosaur skeleton:
• skeletal fragments not common (except in Asian dune deposits)
• seen once every week or so, in DPP
• great mass of fragments, numerous parallel pieces of ribs, line of disintegrating vertebrae
• dinosaur skeletal elements tend to disarticulate (mammal skeletal elements tend to stick in skeletal units)
• skulls are usually lost
• skulls, if found, are usually crushed, so that the palatal elements are obliterated
• skeletons are usually of sub-adult animals

Collecting Dinosaur Bones

• TV Documentaries, wild side cartoons, children's books
• big game dinohunters and dinotrackers
• actors (youth and vigor, age and wisdom)
• hegira to site (anticipatory excitment)
• piles of bleached bones scattered among barren buttes
• discovery (change of perspective as result of discovery)
• setting sun (awed by what remains to be done - eternal platitudes)
• truthful dinosaur films not made, just document preconceptions of filmer

• commercial collectors replacing university collectors
• dinosaur trackways lot of fun - haven't found many (usually seen in X-section)
• getting stuck
• discomfort (fatigue, sun burn, heat, cold, digestive problems)
• usefulness of compilation of reference illustrations
• learning how to recognize fossil bones at beginning

• few things mess up concentration as much as being in bear (lion) country
• field work is serious and hard, reputations to sustain
• some are naturally gifted, support them (Africans, Chinese, Berbers)
• overcome discouragement and persist, persist, persist
• encourage each other
• when something found, usually alone - enjoy it

• cold storage disease
• billions of curious small boys (wanting ball-points)
• politely eating repulsive health hazards

• fleeting room temperature conditions
• sunrises, sunsets
• hospitality, rancher, Mongol, Moroccan, Egyptian

• matrix difficult in western interior, so easy in deserts of Asia and Africa
• skeleton two months to collect, two years to prepare (2-3 people)

• bones overprepared in field
• bottom falls out when cast turned over
• plaster not allowed to "set" sufficiently
• cast not properly reinforced
• half of exciting discoveries made in the lab

Quality of Dinosaur Skeletons, Mounts in Museum

• composite skeletons, bane of restoration
• bones, if real, to significant extent distorted and crushed
• bone heaven - vet school mammal skeletons, so easy, so beautiful, so instructive

II. MAMMALIAN GIANTS, THE ERA OF ELEPHANTS

In other words, the elephants got in the way.

• forgotten knowledge of ancient elephants
• evidence of Classical gods
• evidence of monsters drowned in the Great Flood

• Footprints 8-10 year old boy (oldest known sapiens footprints)
• Angular line symbols resembling writing

20,000 yrs BP - 47-year-old male mammoth weighing about 15,000 pounds (7,000 kilograms), attempt at cloning

• Siberian mammoth became extinct about 3,700 years on Wrangel Island, Siberia
• Marrow leaking from bones, span 40,000 to 3,700 yrs BP - 1,700 BC
• Dwarfs and normal size, MacPhee, AMNH, extinction by disease
• Extinction wave proceeded toward the "outback" - first-hand knowledge, even legends of great, hairy elephants were lost

Egypt

• 50 myr old whales, Arsinoitherium
• Egyptians regarded the Fayyum as the origin of all life forms
• possibility of dinosaur bones

• myr old mammoths, hippos, giant cattle
• 3,100 BC, near Cairo, drilled shark tooth
• 1,300 and 1,200 BC, Asyut - 3 tonnes of black , river rounded bones to Set

• several myr old articulated skeletons of mastodons, huge giraffes
• third and second centuries BC, the secret burial mound of Osiris (Mastodons)
• Phlegon, second century AD, giant skeletons do exist here

• 32 classical authors (Adrienne Mayor, The First Fossil Hunters)
• from 4th Century BC to 4th Century AD, over 1,000 years
• discoveries of elephant bones supported myths of Classical gods
• classical myths supported by elephant finds

Medieval Europe

• giant bones belonged to giants, saints and "celebrities" from antiquity
• mammoth and rhinoceros skeletons arranged in upright positions and displayed as antediluvian giants, primitive cavemen, and even historical Visigoths and other barbarian warriers (Mayor, p. 77).
• 1371 - elephant skeleton discovered in Sicily, thought to be the Cyclops, p. 7
• 1613 - elephant bones attributed to "Teutobochus" giant king of a German tribe defeated in 105 BC by Romans, p. 77

• 300s BC: Volga ivory to China
• AD 900s - fossil ivory exported to southern Europe and Central Asia
• 1200s - Siberian ivory in Mongolia
• 1582 - Russian conquest of Siberia
• 1611 - mammoth tusk sent to London
• About 300 years ago, bones were finally recognized as belonging to extinct elephants (Cuvier)
• ca 1680-1930: tusks from at least 47,000 mammoths, 34 mammoth carcasses had been recovered

• ca 1520 - Elephant bones found by Tlaxclalans, sent by Cortez to Charles I of Spain
• many elephant discoveries by native Americans recorded during time of European exploration
• before 1739 - elephant teeth and bones identified in SC by African-born slaves
• British asked every tribe they met about "giant tusks," hoping to compete with Russian mammoth tusk market
• 1803-1806 - Lewis and Clark requested by Jefferson to search for living elephants in western North America

III. DEVELOPMENT OF THOUGHT

Famous thinkers, swings and near misses:

Anaximander of Miletus (ca. 611-547 BC) - marine fossils indicate that all life originated in water, all living things are related and changed over time.

Xenophanes (sixth century BC) - cyclic changes in sea level destroyed life, life generated anew. All land once covered by sea - in a rare example of empirical proof, cited sea shells on mountains. Evidence was universally accepted [Xanthos of Lydia (fifth century BC), Herodotus, Eratosthenes (285-194 BC)]

Empedocles (fifth century BC) - deplored literal belief in myths (p. 215) - in the time before humans, many kinds of wonderful creatures existed.

Plato (ca 429-347 BC) - variations in organisms are imperfections, deviations from the ideal - suggested that climate caused life-forms to change over time. Humankind "existed for an incalculably long time from its origin"

Aristotle (fourth century BC) - fixity of species, possibly to discourage popular interest in the bizarre (based on old bones?), developed a theory of classification - Scala Naturae

Palaephatus (fourth century BC) - the only ancient author to explain a monster myth as a misunderstanding of real animal remains (p. 221).

Lucretius (first century AD) - larger animals occurred in past but died out as food resources dwindled or they were unable to reproduce. Hybrids, such as human-horse centaurs, were impossible. "Everything living survived since the beginning of the world through cunning, prowess or speed (p. 216)".

Philostratus (ca AD 200-230) p. 222-223: Apollonius (1st Century A.D), "I agree that giants once existed because gigantic bodies are revealed all over earth when mounds are broken open. But it is mad to believe that they were destroyed in a conflict with the gods." - encouraged search for a natural explanation.

Augustine (AD 354-430) some people refuse to believe that animals were once much larger than now - large bones revealed by erosion are tangible proof

Adrienne Mayor: "..what survives of [classical] philosophical writings strongly suggests that, for whatever reason, the philosophers opted out of the "unknowable" problem of giant bones. But inquiry proceeded without them, resulting in natural knowledge based in experience and expressed in geomyths. The myths were not a formal theory in the modern sense.." (p. 226)

476 - last Roman emperor in west deposed

Medieval world view: (Birth and Development of the Geological Sciences, F. D. Adams, 1938): Philosophical speculations continued for 1,000 years, based on classical world view

• Albertus Magnus (ca 1199 - 1280) student of Aristotle
• Thomas Aquinas (ca 1224-1274)

Nicholas Steno (1638-1686) - over a thousand years from the fall of Rome

• Anatomy - shark teeth, fossils buried in once horizontal sediments
• Principle of horizontality
• Principle of relative time (strata), principle of superposition
• Lower rocks without fossils (before life), upper ones with fossils (flood) - first definition of periods in earth history

• 1815 - Geologic map of England, Wales and part of Scotland
• 1819-1822 - 21 colored maps of the Geological Atlas of England and Wales
• Characterized rock strata by their fossils
• used to recognize pre-coal strata by drilling
• 1794 - supervised digging of Somerset Canal in southwestern England (6 years)
• sequence of rock types plus characteristic fossils repeated, as in other side of England
• principle of faunal succession
• used fossils as well as rock type to identify strata

Cretaceous (1722) - A "period of chalk," based on chalks in northern Europe 146-65 Million Years Ago

Triassic (1834) - A "period of three layers," based on lagoonal sediments, Germany 245-208 Million Years Ago

Geologic time had "recently" been discovered to be as much as 1.5 byr (1938)

IV. VESTIGES OF REPTILIAN GIANTS

ca 430 BC - According to Herodotus, dinosaur skeletons inspired the legend of the griffen, Sycthian-Issidonian miners looking for placer gold discovered small, beaked dinosaur skulls in the Gobi Desert.

European myths (listed by Meyer, but not dated)

• Rhine Valley - tracks may have inspired the legend of dragon slain by Siegfried
• Print of Devil's toenail in the stonework of Christ's Church, Cheshire

These were giant lizards, not mammoths

1822 - discovery of Iguanodon by Gideon Mantell (1790-1852), described in 1825
1824 - Buckland (1784-1856) publishes Megalosaurus - "Stonesfield monitor" earliest recognition of group of long-extinct reptiles
1825 - Mantell proposes former existence of a giant reptilian herbivore (new concept)
1833 - discovery of Hylaeosaurus by Mantell
1834 - discovery of the partial skeleton of the Maidestone Iguanodon
1837 - discovery of Plateosaurus by Christian von Meyer (1801- 1869) from Germany
1838 - naming of Poekilopleuron by Eudes-Deslongchamps from France
1841 - naming of Cetiosaurus by Richard Owen (1804-1892)
1842 - naming of DINOSAURIA by Own

[According to the OED: "Scientist" 1840 - Whelwell, Philos. Induct. Sci. "We need very much a name to describe a cultivator of science in general. I should incline to call him a scientist." From scientia L. knowledge.]

1853-4 first wave of "dinomania" at Crystal Palace, hegemony of ancient elephants ends

V. THE BEGINNING OF THE DINOSAURIAN ERA

• 1869 - Exploration of the American West for dinosaurs began
• Link between cities, deserts and dinosaurs
• In farming country and the forests to the taiga it's still elephants (or whales)

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