Geology 105 Test 3 Questions

Name three major reptilian groups.

*Anapsid (Turtle) *Synapsid (mammal) 1 hole *Diapsid 2 holes

What were the Thecodonts?

*Crocodile-like ancestor *Socket-toothed reptiles

What are some of the advantages of being very large?

*Diet: large bc the food supply was of low quality, and had to eat more of it. *Too big to be eaten *Reproduction

What are the differences between the two main types of Sauropods?

*Diplodocids* -soft, aquatic vegetation -nipping or raking the fronds -browsed *Macronaria* • Macronarids ate tougher vegetation • Conifers • browsed at a high level

Compare and contrast Ichthyosaurs and Dolphins

*Ichthyosaurs* -marine reptile *Dolphins* -Marine mammal

How would you describe the late Triassic dinosaurs?

*Low Diversity *Small Size *bipedal

What is the difference between the arms of Ornithominids and Maniraptors?

*Ornithomimids* -long arms, light bones, long tail and neck, quick moving NO TEETH *Maniraptors* -long arms -Hooked claw -teeth

Why do big animals lose heat slower than small animals?

*Thermoregulation Big animals can get overheated

? 6. How are monotremes, marsupials, and marsupials different with respect to the birth of their offspring?

*monotremes: Egg laying mammals *marsupials: live birth, *marsupials: live birth

Did dinosaurs have color vision? How would one know?

-Best guess, yes they had color vision • Dinosaur descendants (the birds) and dinosaur relatives (present day reptiles) have color vision

Name three important groups of vertebrates that became extinct at the Cretaceous/Tertiary boundary.

-Dinosaurs -marine reptiles -ptesosaurs

What were the possible functions of Stegosaur's dorsal, bony plates?

-Dump heat -sexual attraction -defense?

how did Plesiosaurs and Ichthyosaurs feed?

-Gastroliths: Rocks used for digestion and ballast (plesiosaur)

Could Ornithopods chew their food? How do you know?

-Grinding Teeth

What characteristics do Stegosaurs and Ankylosaurs share?

-Herbivores -Dermal bones

What characteristic determines the difference between a Dinosaur and a Thecodont?

-Hole in hip socket Dinosaur is open, thecodont is not

Was T. rex. a predator or scavenger? Cite your evidence.

-Large olfactory lobes -legs for walking long distances -Short - arms too weak to grab prey - Slow

. Describe the earliest known mammal, Morganucodon. When did it live? What was the size, morphology, and ecology of Morganucodon?

-Late Triassic -Egg laying mammals -Small in size and weight -Large brain -small jaws -insectivorous

What did Sauropods eat? How do you know?

-Low quality food and lots of it (reason for large size) -plant matter

What characteristics are shared between Thecodonts and Dinosaurs?

-Over bite -stance -bipedal -carnivores

How did Ichthyosaurs give birth? How do we know?

-Ovovivparous: Eggs hatched inside mother and then born alive in water We know this from fossils

What is the importance of feathers?

-Sexual Attraction -warmth -colors preserved

How did Ankylosaurs protect themselves from predators?

-Tail club

9. What is a mammal?

-Warm-blooded -Air Breathing -Specialized teeth They only have hair, mammary glands, three middle ear bones, two sources for middle ear bones

What can the study of eggs, nests, and the size distribution of babies add to our knowledge of dinosaur behaviors?

-We can tell how the animals cared for their young, if they did.

How can we tell that dinosaurs did not walk with a sprawling gait and posture?

-ankles

What structures that are found in Dinosaurs can be attributed to sexual selection?

-plates -color -horns

What were the Mosasaurs? Mosasaurs related to what living animal?

-true lizards -CLose relatives of monitor lizards

Why did Sauropods get so large? What is the advantage of being large?

1. Diet 2. Too Big to be eaten 3. Metabolic Advantages That's Hot! 4. Reproductive success

What three features are found in Archosaurs?

1. antiorbital fenestrae 2. mandibular fenestrae 3. Thecodont teeth

Discuss the steps in the transition from Therapsid reptiles to mammals. What were the major innovations during the transitions? Be sure to include changes to the jaws/ears from reptiles to mammals

1.) Therapsid (Synapsid skull, upright stance, different tooth pattern) 2.) Theridonts (Mammal like tooth pattern) 3.) Cynodont (ancestor to mammal)

Theropods are a diverse group. What characteristics do most Theropods share?

3 toes grasping fingers

What Ornithischian dinosaurs were social? Is there evidence for herding? Parental Care?

Ankylosaurs were not social because they were never in groups benefit to being social was protection

Contrast features that Archaeopteryx had or lacked with a closely related Theropod and with a more modern bird

Archaeopteryx- teeth and hook on feet and wings, same hip Maniraptors- Hooks on feet and wings, teeth, hip Birds-No teeth, no hooks, but they fly and so do Archaeopteryx

What is the evidence that birds evolved from small carnivorous dinosaurs? What is Archaeopteryx? Why Archaeopteryx considered a "missing link?"

Archaeopteryx: Descent with modification-earliest bird

How did each of the Ornithischian dinosaur group protect themselves from predation?

Armored plates ,spiked on tails, clubs on tails, living in groups

Why are there many Plesiosaur fossils found in Kansas?

Because there used to be an ocean there.

Why do we think that birds and not pterosaurs survive the Cretaceous Extinction event?

Birds are alive today

What are the Lepidosaurs? How are they related to Archosaurs?

Both are diapsid Lepidosaurs: lizards and snakes

If Chris Platt and a Stegosaur appeared together on Jeopardy, who would win and why?

Chris Platt because Stegosaur has a VERY small brain

. What are the purposes of the Ceratopsian headgear? What is the best explanation for the bazaar headgear of some Ceratopsian dinosaurs?

Could possibly be for protection of their vulnerable neck area, for fighting for mates, or for thermal regulation

7. What is the relationship between Cynodonts and early mammals? Explain and cite evidence.

Cynodonts are ancestors to the mammal

. What are dermal bones? Which dinosaurs have these bones?

Dermal Bones: Body covered with bony plates set in the skin -Ankylosaurs/stegosaurs have dermal bones

. What major groups of reptiles are Archosaurs?

Diapsid

When did the dinosaurs first appear? They evolved from what reptilian group? What other major tetrapod group evolved at the same time as the dinosaurs?

Dinosaurs first appeared in the late Triassic and was called the Herrerasaurus. It was the very first dinosaur that was about the size of a chicken. They evolved from Thecodonts and specifically Euparkeria. Mammals evolved in the late Triassic with the dinosaurs.

. What similarities and differences did Pterosaurs have compared with flying birds?

Eat the same, fly

What are gastroliths? What is the importance of gastroliths?

Gastroliths are rocks that dinosaurs swallowed that stayed in their stomach and helped them digest food.

What is the function of the dome of the Pachycephalosaur?

Intraspecies head butting (dominance) and sexual selection.

Why do we think that some Ichthyosaurs were deep diving reptiles?

Late Jurassic Ichthyosaur-Ophthalmosaurus •Large, Dolphin-like (up to 6 meters) •Thick body, large vertebral column •HUGE eyes •Hunted in Deep waters

How did Plesiosaurs reproduce?

Live birth at sea

8. What characteristics do you share with Theriodonts?

Mammal like tooth pattern

3. Describe the effects of the meteorite impact on Earth's systems and how these effects would have led to the mass extinction.

Meteorite incinerated where it hit blocked sunlight and stopped photosynthesis

What is the difference between a bird and a dinosaur?

NOT dinosaurs. POWERED FLIGHT=BIRDS

. Do all Theropods have teeth? Give examples.

No- Ornithomimids had toothless beak

Could some dinosaurs vocalize? Which groups? How do we know?

Orthopods

The greatest recorded mass extinction to affect Earth occurred at the end of which period?

PERMIAN

Describe a typical Late Triassic Dinosaur such as Herrerasaurus.

Small, bipedal

From what reptile group did mammals evolve? What are the differences between reptile and mammals?

Synapsid

10. What is special about the duck-billed platypus? By examining the duck-billed platypus what can we learn about early

The platypus excretes milk from a milk field, rather than from nipples

Pterosaurs feed in a diversity of ways. How did they feed (list several) and how do we know?

The same ways that birds eat today like darwins finches

What reptiles gave rise to pterosaurs?

Thecodonts

2. Compare and contrast pterosaurs with birds.

They both could fly except the pterosaurs were much larger than any bird, the size of some planes. Pterosaurs had bird like air sacs- reduced density and improved breathing.

What evidence links T. rex to birds?

Tissue in the bone .

What were the hazards of being a dinosaur egg or hatchling?

Vulnerable

How could one identify a pterosaur from the Triassic vs. one from the Cretaceous?

Whether it is a Rhamphorhynchoids (triassic) or Pterodactyloids (cretaceous)

By the end of the Cretaceous were there many types of mammals? Explain

Yes

Were pterosaurs good fliers?

Yes very strong wings

Did sauropods grow fast

Yes- 8-10 years to reach maturity

8. What would the world be like if this mass extinction did not occur?

dinosaurs would be alive

6. Why does the Iridium anomaly point to a meteorite impacting the Earth?

found in asteroids

5. What caused this mass extinction?

meteorite

Were Sauropod good parents compared to some Ornithopods?

no bc we did not find nests showing no babies in them

What is 'otogeny' and how does it relate to Pachycephalosaurs and Ceratopsians?

otogeny: change in body structure as it matures

What are some hypotheses for the original function of feathers?

sexual selection and protection

Describe a typical Mesozoic mammal.

very small noctural lived underground or in trees good hearing carnivores (ate insects)

Did at least some dinosaurs have feathers? How do we know?

yes-

Describe the two types of pterosaurs. Describe the pterosaur wing. How does it differ from a bird's wing?

• 1. Rhamphorhynchoids - Long tails -First Pterosaurs -teeth 2. Pterodactyloids -Shorter tails

1. Summarize the evidence for a meteorite impact causing the mass extinction at the end of the Mesozoic era.

• Iridium is rare on Earth • common in asteroids

9. What is so special about Purgatorius?

• Purgatorius ancestor to modern primates • Had the group of rat-like animals to which Purgatorius belonged died out with the dinosaurs, we humans never would have evolved.

2. Why are Extinctions important?

• Resets the Evolutionary Clock - Many open niches - *Opportunities* for diversifications - New species become dominate

What functions did wings serve before flight?

• Running • Gliding • Display

How did Maniraptors catch and kill their prey?

• Sharp teeth • giant *hook-like claw* • Specialized hunters • Long arms

4. What is shocked quartz and how was it formed?

• Unmistakable microstructures • North America -- Most found • Europe and in Pacific Ocean sites -- only a few fragments *This is evidence of impact*

Were pterosaurs dinosaurs? Explain the relationship between pterosaurs and dinosaurs

• hollow bones, • large brains with well-developed optic lobes, and • powered flapping flight.

How were Sauropod bones similar to bird bones?

•Hollow bones bc sauropods were so massive -Birds also have hollow bones riddled with holes