Exam 3

Question 1

Give an example of (a) allopatric speciation, and (b) speciation via simple hybridization

Answer 1

a - Galapagos Finches
b - The “Anomalous Sunflower”

Question 2

In what type of organism is Speciation via Disruptive Selection common? Give an example

Answer 2

Parasites –> apple maggot fly

Question 3

In what group of organisms is Speciation via Hybridization and Polyploidy common? Give an example

Answer 3

flowering plants –> wheat

Question 4

List 2 pre-mating isolating mechanisms. Which was said to probably be the most important isolating mechanism, overall?

Answer 4

Behavioral, habitat, temporal, mechanical, chemical

• behavioral

Question 5

what are the 3 types of post-mating isolating mechanisms?

Answer 5

• zygote mortality
  gamete mortality
  sterile hybrids

Question 6

What are 2 evolutionary phenomenon commonly seen in connection with adaptive radiation? give an example of each

Answer 6

co-evolution –> flowers & pollinators, etc.
convergent evolution –> placental & marsupial mammals, etc.

Question 7

list 2 wats in which primates are different from many other mammals

Answer 7

reliance on vision, nails, thumbs, etc.

Question 8

what are the 2 most important ways in which hominins differ from other hominids?

Answer 8

bipedal locomotion & large brains

Question 9

what species did “Ardi” belong to? Give one fact about that species

Answer 9

Ardipithecus ramidus –> unusual foot, flat but with opposable big toe

Question 10

what species did “Lucy” belong to? Give one fact about that speceis

Answer 10

Australopithecus afarensis –> very intermediate between ape ancestor and modern humans, etc.

Question 11

what is the approximate “Encephalization Quotient” of modern humans?

Answer 11

~ 7

Question 12

What hominin was the first one to live not only in Africa, but also other continents of the “Old World”? What was its characteristic stone tool?

Answer 12

Homo erectus
Acheulean handaxe

Question 13

What 2 other recent human groups have contributed genes to the genomes of modern Homo sapiens?

Answer 13

Neanderthals and Denisovans

Question 14

What is unusual about the species Homo floresiensis? What general evolutionary/ ecological phenomenon might it be a human example of?

Answer 14

very small size
Island dwarfing or “the island rule”

Question 15

what is “Liebig’s Law of the minimum”?

Answer 15

An organism is limited by the scarcest resource (limiting factor)

Question 16

How does the surface area: volume ration change as organisms get larger?

Answer 16

as size increases; surface area: volume ration decreases

Question 17

With respect to maintaining a high, constant body temperature, what problems are faced by a very small animal and by a very large animal?

Answer 17

small –> relacing lost heat due to large SA:V
large –> losing heat due to small SA:V

Question 18

What is Bergman’s rule? what is allen’s rule?

Answer 18

B –> animals in cold areas have larger bodies
A –> animals in cold areas have shorter appendages

Question 19

How could metabolic rate change as temperature goes up from 10 degrees celsius to 20 degrees celsius for a Poikilotherm? for a homeotherm?

Answer 19

P: m.r. increases
H: m.r. decreases

Question 20

For an animal of a given body size, rank these three modes of locomotion from least efficient to most efficient: flying, running, swimming

Answer 20

running, flying, swimming

Question 21

What is the “Principle of Allocation”?

Answer 21

When resources are devoted to one structure or function, they cannot be allocated to others natural selection favors optimal trade-offs in allocation

Question 22

List three traits typical of an “r-selected species” and three traits typical of a “k-selected species.”

Answer 22

• r: small size reproduce at young age many offspring no parental care, etc.
• k: large size reproduce at older age few offspring much parental care etc.

Question 23

What is “Lack’s Principle”? What is one reason that some species seem to violate it?

Answer 23

Birds lay the number of eggs in a clutch that results in the greatest number of surviving offspring.
Some don’t. because there is a trade-off between that and decreased parental lifespan

Question 24

What is the difference, in Ecology, between Dispersal and Dispersion?

Answer 24

• dispersal –> one way movement away from location of birth or later residence
• dispersion –> spacing pattern of individuals in a location

Question 25

What is the difference, in Ecology, between Dispersal and migration?

Answer 25

D: one way movement away from location of birth or later residence M: movement with an outward and a return component, usually seasonal

Question 26

Give 2 critereia that honey bee swarms are looking for when seeking a new hive site, and what the adaptive reason is for those two criteria

Answer 26

- >3 m high --> safety from predators - hole < 60 cm2 --> safety from predators, heat control - opening at bottom --> lessen heat loss etc.

Question 27

List 4 types of "Primary" anti-predator defenses, and 3 types of "secondary" anti-predator defenses

Answer 27

1) - camouflage - maskerade - counter - shading - descriptive coloration - removal of clues 2) - speed, vigilence, escape spaces, unpredictable movement, startle, misdirection, - physical/chemical defense, pursuit deterrence signals, interspecific defenses - aposematism, batesian and mullerian mimics, temporal avoidance, disperse widely

Question 28

List the 2 "universal costs of living in a social group" and 2 "occasional costs of living in a social group"

Answer 28

- increased competition with conspecifics - increased risk of parasitism & disease - attraction of predators, conspecific brood parasitism, risks to offspring from conspecifics

Question 29

list 4 foraging advantages of living in a social group

Answer 29

1. access to others' information 2. increased capture rates 3. catch larger prey 4. retain or theft of kills

Question 30

list 4 anti-predator advantages of living in a social group

Answer 30

1. increased vigilance 2. alarm calls 3. mobbing 4. "sheltered effect 5. dilution effect 6. confusion effect

Question 31

With respect to the explanations that have been given for "altruistic behavior" of animals, list one that: a) is now almost universally rejected: b) requires advanced cognitive ability: c) is believed to be the most common and important: d) is exemplified by the hosts of European cuckoo birds:

Answer 31

a) group selection b) reciprocity c) kin selection d) manipulation by natural enemies