Lesson 3

Question 1

When we try to understand the diet or behavior of dinosaurs, we often look at adaptations in ______ animals

Answer 1

modern

Question 2

What anatomical features should you look at to understand what an animal might’ve eaten?

Answer 2

jaws and teeth

• flat teeth= grind up veg
• sharp teeth= pierce prey

Question 3

carnivores that are specially adapted to eat insects=

features of these carnivores?

Answer 3

insectivores

• sharp teeth to pierce insect exoskeleton (or triangular beak in birds)

Question 4

carnivores that are specifically adapted to eat fish=

features of these carnivores?

Answer 4

piscivores

• elongate jaws (to reach far & snap fast) and tall conical teeth that are good at spearing/ gripping fish

Question 5

t/f
all piscivores have teeth

Answer 5

false

piscivorous birds (eg loons) have fish-skewing beaks

Question 6

procumbent dentition=

Answer 6

the teeth in the front of the mouth point forward at an angle rather than straight up & down
- many piscivores have this
- allows the front tips of the jaws to be used to impale fish

Question 7

durophagy=

Answer 7

a type of eating where the carnivore eats very hard food (like bones).

• adaptations for cracking bones/ shells: deep powerful jaws and thick rounded molars

Question 8

____ eat both plants and animals, so have a mixture of sharp and flat teeth

Answer 8

omnivores

Question 9

do dinos lose teeth like mammals?

Answer 9

no!

mammals only have 2 set of teeth (once you lose your baby teeth you only have the one set)

dinos replaced each tooth every 1.5-2yrs no matter what
- new teeth always growing out beneath the old ones (old roots dissolve)

Question 10

when the root of a tooth becomes almost completely resorbed, the tooth becomes ____

Answer 10

loose

just like out baby teeth

Question 11

A large hadrosaur had around _____ teeth in its mouth at any one time, if you include both the teeth being actively used in eating as well as all the replacement teeth.

Answer 11

1000

Question 12

would the teeth of a herbivore or a carnivore wear down more quickly?

Answer 12

herbivore’s teeth wear down quicker because they grind up their food

= had more replacement teeth growing beneath the current teeth

Question 13

a large set of teeth is called a

Answer 13

dental battery

Question 14

dino teeth are often inset from the outer surface of the skull. Why?

Answer 14

so that the chewed up plant material contained within the cheeks doesn’t drop out of the mouth

Question 15

t/f
dental batteries for grinding plant material are present in both hadrosaurs and ceratopsians, which is evidence that they had a common ancestor

Answer 15

false

they do both have them, but do not have a common ancestor
this is an example of convergent evolution

differences:
- vertical grinding surface in ceratopsians
- horizontal in hadrosaurs

Question 16

the edges of herbivore teeth are kept sharp because they’re formed by ____

Answer 16

enamel

cutting edge to chop of plants before grinding up on the flat sfc of dental battery

Question 17

Which of these animals had a dental battery?
A, Diplodocus.
B, Triceratops.
C, Tyrannosaurus
D, Corythosaurus.
More than one answer maybe correct

Answer 17

triceratops and the hadrosaur corythosaurus

evolved independently though

Question 18

Pachycephalosaurs and Ankylosaurus have small, ___-shaped teeth

Answer 18

leaf

Question 19

in addition to sharp teeth, many carnivorous dinos also had strong, curved ___, useful for grasping prey

Answer 19

claws

Question 20

______ had a large, sickle-like retractable claw on each foot

Answer 20

dromaeosaur (like the velociraptor)

Question 21

what’s one benefit of retractable claws?

Answer 21

they stay sharp because they’re not scraping along the ground all the time

Question 22

Describe some characteristics of the Alvarezsaurd theropod, the Shuvuuia. What might it have eaten?

Answer 22

• long snout & short teeth
• 1 single huge claw on each of its hands
• short, robust arms (strong)
• long, fragile skull
• jaws lined with numerous tiny teeth

termites (dino equivalent of anteaters)

Question 23

How might we determine the diet of dinos without teeth?

Answer 23

gastric mill presence and what is found in their body cavity (eg rocks)

Question 24

______ are ostrich mimics and have been found with ____ inside their body cavity. They had no ____

Answer 24

ornithomimids
rocks
teeth

Question 25

gastric mill=

Answer 25

a muscular pouch in the digestive tract near the stomach that holds swallowed stones (gastroliths).
As the muscles rub the stones together, food passing through the mill is ground up (same function as teeth!)

Question 26

what features might we expect from a dino with very small teeth that are not well-suited to chewing?

Answer 26

large body size
a large gut= food can be broken down in there instead of by teeth

Question 27

sauropods would have used their guts as giant _____ tanks

Answer 27

fermentation

break down cellulose

Question 28

bite marks and shed teeth tell us that theropods fed on dead ____

do we know if they hunted or scavenged them?

Answer 28

herbivores

no, we don’t know, but rarely is an animal purely a hunter or purely a scavenger (usually a mix)

Question 29

cololite=

Answer 29

a mass of fossilized, partially digested food preserved in the stomach of a dino

Question 30

coprolites=

Answer 30

fossilized dino droppings

• can use shape/ content of coprolites to determine which animals lived in which areas