chapter 3

Question 1

paleontology

Answer 1

study of past, study of fossil remains

Question 2

how long has the earth been present for?

Answer 2

4.6 billion years

Question 3

3 eras of geological past

Answer 3

-palaezoic (oldest)
-mesozoic
-caenozoic

Question 4

when was the paleozoic era and what came out of it?

Answer 4

534 million years ago/beginning of Cambrian period, when all ancestors of modern animals arose

Question 5

3 points of the mesozoic era

Answer 5

1. triassic was the first period
2. first dinosaurs, mammals, conifirs, cyads, and therapsids
3. age of reptiles

Question 6

3 ways to determine fossil age:

Answer 6

1. relative dating: based on principle of superposition
2. absolute dating: determined by testing fossil itself or material around it
3. radiometric dating: MOST accurate, based on half-life or decay of isotope

Question 7

5 kinds of fossil formation

Answer 7

1. compression
2. petrification
3. impression
4. cast
5. preservation by sap

Question 8

2 major continents developed after pangea

Answer 8

laurasia and gondwana

Question 9

marsupials and examples

Answer 9

most abundant land mammal on earth, have pouch ex. kangaroos, koala, wombat, opossum

Question 10

placentals

Answer 10

have a placenta, develop inside the human body, greater survival rate than marsupial

Question 11

wallace’s line

Answer 11

boundary that separates Asian animals from Australian animals (between indonesian islands of bali and lombok)

Question 12

Homologous structures

Answer 12

two structures that can share common ancestry but do not necessarily serve the same function (evidence based on anatomy)

Question 13

Analogous structures

Answer 13

structures in different organisms that appear similar in function or form, but occured independently from one another

Question 14

what is it called when analogous structures arise independently

Answer 14

convergent evolution

Question 15

vestigial structure

Answer 15

structure that no longer functions but remains in diminished form