EPS SCI 17 Midterm

Paleontology

the study of the remains of ancient life, including body, chemical, and trace fossils - not just the study of dinosaurs

Gideon and Mary Ann Mantell

named the iguanodon

dinosauria

"terrible lizards" - coined by Sir Richard Owen (1804-1892)

Endothermic

saying that dinosaurs generated their own heat to maintain an optimal body temperature

Edward Drinker Cope

\- 1840-1897 - Worked at the Academy of Natural Sciences in Philadelphia

- Published over 1,400 papers

\- Named more than 1,000 vertebrate species

Gastroliths

Swallowed stones in the stomach that aid in digestion

Paleobiology

Paleobiology is a growing and comparatively new discipline which combines the methods and findings of the life science biology with the methods and findings of the earth science paleontology.

Ice age mammals

are not considered dinosaurs for a multitude of reasons

ex. did not live in the same era (Cenozoic - Quaternary)

Dinosaur Hips

Ornithiscian - bird hips

Saurischian - lizard hips (sauropods and theropods)

Digitigrade

tiptoe walking

facultative

capable of but not restricted to a particular function or mode of life

ex. ornithopods = bipeds or facultative quadrapeds

Battery teeth

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hundreds of ***teeth*** which were stacked in rows upon rows and formed a grinding surface to process plant foods

If you wanted to take your time machine and go hunting for Carcharodontosaurs what's the best place you could travel to to have a chance of seeing one?

Any of these, they were cosmopolitan (worldwide)

Which dinosaur would have been the "butcher of the Jurassic" in North America?

Allosaurus Fragilis

Which of the following characters relate to enhancing bipedal movement in theropods?

stiffened tails

Which of the following does NOT belong in tetanurans?

ornithopods

The K/T (End Cretaceous) Extinction is at the END of which ERA?

Mesozoic

Which of these dinosaurs or dinosauromorphs lived in the Triassic?

\- Eoraptor

\- Herrerasaurus

\- Coelophysis

If you wanted to take your time machine and go hunting for sauropods what's the WORST time/place you could travel to to have a chance of seeing one?

Cretaceous of North America

What are some geological reasons that we are able to reconstruct the members of Late Jurassic dinosaur communities so well?

Dinos were abundant and fossil-filled rock formations are exposed to the surface

Post-orbital

behind the eye

synapsid

only 1 post-orbital fenestrae

diapsid

2 post-orbital fenestrae (one behind eye and one behind and above the eye)

amniotic egg

an egg with a shell and internal membranes that keep the embryo moist, fluid helps to protect the developing embryo from physical danger

William Buckland (1784-1856)

\- first to name a dinosaur (Megalosaurus - a theropod)

\- coined the term "paleontology"

transitional fossil

fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group

\- ex. first = Archaeopteryx

Othniel Charles Marsh

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\- 1831-1899

\- Helped found the Yale-Peabody Museum

\- Worked at the US Geological Survey and was president of the National Academy of Sciences

\- Named 26 genera of dinosaurs, including *Apatosaurus*, *Allosaurus*, *Diplodocus*, *Stegosaurus*, and *Triceratops*

Marsh and Cope

\- Both found the large collections of bones in the American West

\- Both did much to promote dinosaur research in the late 1800's

hypothesis vs. theory

A hypothesis is either a suggested explanation for an observable phenomenon, or a reasoned prediction of a possible causal correlation among multiple phenomena. In science, a theory is a tested, well-substantiated, unifying explanation for a set of verified, proven factors.

melanin

A pigment that gives the skin its color

Iridiophores

pigment cells that reflect light using plates of crystalline chemochromes made from guanine. When illuminated they generate iridescent colours because of the diffraction of light within the stacked plates.

countershading

Dark colors (top) visible from above when the background is dark ground and light colors (bottom) visible when the animal is backlit

Ecology

The study of how living things interact with each other and their environment

Mammutus

has hair, live birth = not dino

archosaurs

Archosaurs are a group of diapsid amniotes and are broadly classified as reptiles. The living representatives of this group consist of birds and crocodilians.

\- crooked ankle

Phylogeny of dino relatives

homologous

Structures in different species that are similar because of common ancestry.

tetrapod

vertebrate with four limbs

Why move to land?

1. escape predation
2. less competition
3. more resources (oxygen, sunlight, and food?)
4. easier to move around

absolute dating

any method of measuring the age of an event or object in years

Taxa (taxon)

a grouping of organisms 

ex. a species, a genus

traits

Characteristics that are inherited

antiorbital fenestra

ahead of the orbit

The early dinosaurs lived on which continent?

Pangea

What process powers continental drift?

Convection within the earth

Which organisms were the dominant, top predators in the Triassic?

Pseudosuchians

What is the term for two groups of organisms that resemble each other because of similarities in lifestyle and environment (not close ancestry and shared traits)?

Convergent

The hot and extreme weather in the Triassic was caused by?

High levels of carbon dioxide in the atmosphere

The early dinosaurs lived on which continent?

Pangea

In science, the usefulness of a claim (or hypothesis) is directly related to:

the testability of the claim

Which of these has __all__ of the same skeletal traits we have used to define a dinosaur?

Billie, Professor Brown's parrot

Dinosaur fossils greater than 200 million years old would be found in which time PERIOD? Use the time scale from lecture, online, or the first pages of Rise of the Dinosuars

Triassic

All theropods were carnivorous

False

If energy present at each step in the food chain is visualized as a pyramid of consumers, plants are on the bottom and apex predators are at the top. The available energy at each level narrows down substantially. Where does most of the lost energy go?

Into heat

What does it mean when we say theropods were "airheads"?

Their skulls were filled with air sacs

The name Tetanurae refers to which shared character (trait) of this theropod group?

Stiff Tails

Why is the tyrannosaurid group of dinosaurs found globally when so many other dinosaur groups were restricted to one place and time?

tyrannosaurids originated early enough that Pangea existed and they occupied it before it broke up

You're wandering around Africa in the Cretaceous and you see a brutal scene of a theropod killing a baby titanosaur. Which of the following taxa does the theropod most likely belong to?

Abelisaurs

Which of these is not a rock type that would preserve fossils?

Igneous Rock

fenestrae

a small natural hole or opening, especially in a bone

Ceratosaurus

Allosaurid Theropod

Smallest Allosaurid

It was the only carnivorous dinosaur that had three horns.

Archaeopteryx

Saurischian Theropod

Late Jurassic

An intermediate fossil that shows both reptile and bird characteristics.

Herrerasaurus

Saurischian

Late Triassic

One of the earliest known dinosaurs

Majungasaurus

Abelisaurid Theropod

Tiny arms

Late Cretaceous

Had evidence that Majungasaurus and Majugatholus were the same animal

Tyrannosaurus Rex

Last large theropod to rule

Late Cretaceous

Robust wide skull, heaviest land animal, crushing bite. King of Cretaceous

Deinonychus

Dromaeosaurid Theropod

Early Cretaceous

"Terrible claw"; a genus of carnivorous dromaeosaurid coelurosaurian dinosaurs, with one described species

Led to start of the dinosaur renaissance

Velociraptor

Dromaeosaurid Theropod

Late Cretaceous

Had a large manus "hand" with three strongly curved claws, which were similar in construction and flexibility to the bones of modern birds

May have had feathers

Compsognathus

FIRST Theropod

Late Jurassic to Early Cretaceous

Spinosaurus

Spinosauridae Theropod

Cretaceous

Likely the largest and tallest Dino. Though very slim and light.

Sail backs and duck bill snout

Semi-aquatic (dense bones)

Allosaurus

Theropod

Late Jurassic

One of the earliest dinosaurs found. Gave name to HUGE allosaurids

Reduce bone strength but very light

Oviraptor

Theropod

Late Cretaceous

Carried eggs, may have eaten eggs

Possibly omnivore

Ornithomimus

Late Theropod

Very fast

Cretaceous of Laurasia, possible also Gondwana

Some have bizzare feeding adaptations (duck-like beaks, diverse in size and diet)

Therizinosaurus

Theropod

Late Cretaceous

Known for their huge claws and resembled sloths

Possibly herbivores

Microraptor

Dromaeosaur Theropod

Early Cretaceous

Among the smallest-known non-avian dinosaurs (1kg)

Camarasaurus

Sauropod

Late Jurassic

Giant herbivores

Hollow chamber in vertebrae

Diplodocus

Herbivorous dinosaur with a long neck and tail, lived during the Late Jurassic period. One of the largest land animals ever discovered, reaching up to 90 feet in length and weighing up to 25 tons.

Plateosaurus

Sauropod-ish

Late Triassic North America

Facultative Bipeds- capable of walking or running on two legs often for a limited period in spite of normally walking or running on four limbs or more

\-Shows transition

Social

Giraffatitan

Sauropod

Cretaceous East Africa

Largest dino until 1990

Reconstructed with upright neck

Controversially located in Berlin

Iguanodon

Ornithopod

Mid-Jurassic to Late Cretaceous

Second dino to ever be identified and named

First described herbivorous dino

Maiasaurus Peeblesorum

Hadrosaurid Ornithopod

Jurassic/Cretaceous

Evidence of parental care

Transition between fast bipedal and duckbilled quadriped herbivores

Phytosaurs

Croc Relatives

Triassic

Sprawled limbs, robust tails, armor plates embedded in the skin, elongate skulls lined with sharp cone-shaped teeth, nostrils faced upwards.

Pseudosuchians

Croc relatives

Triassic

Top Predator in Triassic

Homo sapiens

Modern humans

Dimetrodon

carnivorous mammal like reptile, of the genus ​Dimetrodon

Permian Era North America

Long and usually bearing spinal sails. Look like dinos but only one postorbital fenestra

How did the concept of dinosaurs come to its current state over the past 200 years?

Paradigm shift in the 60s: in 1964, an expedition from Yale University discovers, in Montana, a sickle-clawed "raptor" theropod (deinonychus) One of the Yale paleontologists, John Ostrom, noted that the fossil recovered and related predators presented several bird-like skeletal features. Subsequent studies and research made scientists conclude that birds, and not reptiles, are in fact direct descendants of dinosaurs. Ostrom argued for warm-blooded, active dinosaurs. One of his students, Bakker, argued that Tyrannosaurs and its carnivorous kin were agile predators, able to run fast (almost 40 mph). More recent work indicates that Tyrannosaurus & co actually could barely run. For what concerns herbivores, there's scientific debate going on on whether sauropods could rear up on their hind legs and elevate their necks above the horizontal.

What are the origins of dinosaurs in time and on Earth?

Scientists first began to study dinosaurs during the 1820s when they discovered the bones of a large land reptile they dubbed as Megalosaurus (named by William Buckland) buried in the English countryside. In 1842, Sir Richard Owen first coined the term "Dinosauria". There are "stem reptiles" or early amniotes from 300 Ma, where mammals, birds, dinosaurs, and reptiles all stem from (synapsids and diapsids split from here)

\-Dinosaurs and their relatives share traits: jaws and teeth, vertebral column, amniotic eggs (ancestrally), terrestrial (ancestrally)Synapsids (mammal-like reptiles, not dinos)

\-One postorbital fenestra (skull hole)Diapsids (dinos, birds, living reptiles)-Two postorbital fenestra Archosaurs: closest dino relatives (all about the ankles)

\-Split in ankle anatomy between croc-like animals and dinos/pterosaursOrnithodirans: dinosaur/pterosaur divide 

-Split determined by flight... archosaurs minus flying pterosaurs (leaving all terrestrial)

Dinosaurs: terrestrial diapsids with ornithodire ankles that lived in the Mesozoic, or all the ancestors of the pigeon and Triceratops

What is a dinosaur?

Terrestrial diapsids with ornithodire ankles that lived in the Mesozoic, all ancestors of the common ancestor of pigeons and triceratops

123 hand

234 foot

Several holes in skull (two postorbital fenestra)

Kinetic skull

Upright posture

Hole in hip

Unusual ankle

Terrestrial (no dinosaur was ever fully aquatic or able to fly)

Which vertebrates are the closest relatives of the dinosaurs?

Archosaurs (including crocodilians), can be identified by the ankles, which have a crurotarsal ankle joint (dinosaurs and pterosaurs have a mesotarsal ankle joint)

What major characteristics define Ornithodires?

Ornithodires: Archosaurs that more closely resemble birds than crocodilians

\-Mesotarsal ankles

\-Covered in feathers

\-Lineage where dinosaurs and pterosaurs split

What major characteristics define Ornithischians?

Any​ ​herbivorous​ ​dinosaur​ ​of​ ​the​ ​suborder​ ​Ornithopoda​ ​whose members​ ​usually walked​ ​erect​ ​on​ ​their​ ​hind​ ​legs

\-kinetic skull

\-'bird' hips

\-leaf shaped teeth

\-lower jaw with a predentary bone

\-network of bony ligaments (ossified tendons)

\-stiffen backbone

-North America

\-Ornithischians

What characteristics define Saurischians?

\-Loss of distal carpal V

\-Lizard hipped dinos

-Pubis runs anteriorly and downward

-Twisted thumb (carpal I)

-Includes theropods and brachiosaurus things

What are the 2 main traits that divide Sauropods into Diplodocids vs Macronarians?

Diplodocids

\-single nostril

\-peg teeth

Macronarians

-2 nostrils

\-leaf teeth

Which locomotion-related traits divide Ornithopods into Heterodontids vs Iguandodontids+Hadrosaurs?

Heterodontids -bipedal

Iguanodontids+Hadrosaurs -faculative quadripeds if not pure quadripeds

Which feeding-related traits divide Iguanodontids, Hadrosaurids and Lambeosaurs?

Iguanodontids -not as many replacement teeth

Hadrosaurids -duck bill mouth

Lambeosaurs -staggered replaceable teeth

Which diet characterizes each branch of the Ceolurosaur theopod family tree? Can you point out a skull or forelimb trait to support that answer?

Therazinosaurs

\-Possibly herbivore

\-Sloth appearance and long claws don't suggest hunting or tearing flesh

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Oviraptors

\-Possibly ate eggs, fish, and shellfish

\-beak, no teeth, great crushing power

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Ornithomimids

\-Not carnivore, Omnivore possibly

\-No teeth and very light and fast build

What techniques are used to obtain a relative date for a fossil? An absolute date?

Absolute date: radiometric dating (for rocks not fossils)

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Relative date: Superposition (older vs. younger rocks), principle of original horizontality

When was the Mesozoic and what time periods are in it, in order?

250m to 66m years ago

Triassic, Jurassic, Cretaceous

In what time period did the ancestors of most animals (including that of vertebrates) show up?

Cambrian

How did vertebrates combat dessication?

Adults - thick skin

Young - amniotic egg

What happened in the Permian era before the Triassic

amniotes ruled the land, vertebrates overtook arthropods for goodarchosaurs relatively small and uncommon, except in freshwater realm