module 4 (part 2)+(part 3)

Question 1

todays biologiest belive in the central propositions of evolution:

Answer 1

-that all living things are decended from a common acestor

-that all extant species can change and give rise to new species

example: brown bear (carnvore) —-> giant panda (eats bambo)

Question 2

evidence to support the theory of evolution

Answer 2

1. artificail selection
   -selective breeding of animals & plants [by humans] over 100-1000s of years
   -this method is faster than natural selection
2. fossil records
   -this is strong support of evolution
   -fossils show transitional forms [direct evidence of decendents and modification]
   -many fossils link early extinct species with living species today
   EXAMPLES:
   a. pakicetus (sometimes swam) –> ambulocetus (flippered feet) –> rodhocetus (swimming)
   b. hind leg dinasour –> transitional form –> modern whale [blowhole used to be notrils]
   c. hyracotherium —> horse (molars & hoofs & larger)
   d. archaropteryx was similar to birds but had a free rib cage [reptile —> birds]
3. Biological Design
   -same ancestor but have morpholiogical differences
   EXAMPLE:
   canines –> fox, coyote, wolf, jackal, african dog

Question 3

3. biological designs [evidence to support evolution]

Answer 3

homologus characterics (similar ancestry)
-only homologus are used to infer evolutionary relationships of organisms

analogus characteristics (similar function)

homoplaisious characteristics (appearance)

Question 4

vestigial characteristics

Answer 4

characteristic that have no apparent use

like appendix and tail bone in humans

pelvic bone in whales which used to be for walking

Question 5

comparative embryology homologies

Answer 5

the formation of the blastula in all animals

also ATCG sequences

Question 6

molecular homologies

Answer 6

ATCG sequences

also HOX genes found in all animals was is used for regulation of morphological development in the embryo

HOX genes tell other genes what to do in order to make body parts

Question 7

mystery: why do penguins live in S. hemisphere but not in Arctic and polar bear in Arctic but not in Antarctic?

Answer 7

BIOGEOGRAPHY

Question 8

why are fossils of marine organisms (whales) found on land?

Answer 8

answer 1: sea levels have changed over time

answer 2: plate techtonics have moved

answer 3: environmental changes due to 1&2

example: pangea broke up forming two super contenients

Question 9

microevolution

Answer 9

changes in population

Question 10

macroevolution

Answer 10

formation of new species

Question 11

why couldnt pengiuns are bears meet?

Answer 11

cuz they didnt have time to migrate before the contents broke up. Now they are seperated> penguins never made it above the equator

Question 12

who was alfred russle wallace

Answer 12

father of biogeography

Question 13

why should adjacent areas with similar climate have different animals on them?
[
E.g. fauna and flora of sumatra & Java are more like those on the mainland, while fauna and flora of Papa New Guinea is more like Australia]

Answer 13

this was studied by alfred russel wallace

he found: each great region of the world has its own fauna and flora

specifically, no native species were common on other continents, SO, they must have evolved from its own unique fauna and flora

Question 14

Biogeographically, a mole can look the same as a mole on another contenent but not be related at all. Why is this?

Answer 14

convergent evolution

independantly evolved similar characteristics by being in similar climate. But not related at all

Question 15

what is an example of convergent evolution

Answer 15

two cacti live in differnent continents and are unrealted. But have similar adaptations. this is due to the environment

Question 16

cryptic colouration

Answer 16

blending in/camoflauge

leaf tailed gecko

Question 17

inanimate

Answer 17

showing no signs of life

Question 18

who proposed that soot on trees increased melanin moths in england (natural selection)

Answer 18

Bernard Kettlewell

Question 19

who proposed beak size in finches on galapaogs isl. was caused by dry conditions where plants produced bigger seeds, so finches got bigger beaks. (natual selection)

Answer 19

Peter and Rosemary Grant

Question 20

sexual cannibalism benifits

Answer 20

secures that your genes are passed on since mates only mate once.

[a reproductive investment]
[increases her chances of surviving]
—> high energy nearby
—> contributes to growth of offspring

Question 21

sexaul dimorphisim

Answer 21

where there are phenotypic differences between males and females that may give an advantage in mating (secondary sexual characteristics

Charles Darwin considered it sexual selection
Alfred Russle Wallace thought is was natual selection

Question 22

sexual selection (fitness) two types

Answer 22

intrasexual selection:
between same sex
-fighting each other for right to repoduce
[rams][horn sheep]

intersexual selection:
-having traits that a female will select
[peacock]

usually a combination of both tho [Elk]

Question 23

Two patterns of evolutionary change

Answer 23

Anagenesis
Cladogenesis

Question 24

Anagenesis

Answer 24

single species all evolve into one new species

Question 25

Cladogenesis [more common]

Answer 25

species divide into multipule new species --> leads to ALLOPATRIC Selection --> is the splitting of a population genes become unique overtime cuz of seperation [more common than anagenesis because it realted to geographical isolation]

Question 26

Founder effect

Answer 26

the establishment of a new population by a small amount of indivuals. founding titan lead to population of all the other titans [also galapagos finches]