ANTH 1000 - Ch. 6

Question 1

macroevolution

Answer 1

evoluation above the species level

Question 2

speciation

Answer 2

the process of forming new species

Question 3

isolating mechanism

Answer 3

a factor that separates bredding populations, thereby preventing gene flow, creating divergent subspecies and ultimately (if maintained) divergent species

Question 4

cladogenesis

Answer 4

speciation through a branching mechanism whereby an ancestral population gives rise to two or more descendant populations

Question 5

heterochrony

Answer 5

change in the timing of developmental events that is often responsible for changes in the shape or size of a body part

Question 6

homeobox gene

Answer 6

a gene responsible for large-scale effects on growth and development that are frequently responsible for major reorganization of body plans in organisms

Question 7

punctuated equilibria

Answer 7

a model of macroevolutionary change that suggests evolution occurs via long periods of stability or stasis punctuated by periods of rapid change

Question 8

anagenesis

Answer 8

a sustained directional shift in a population’s average characteristics

Question 9

derived

Answer 9

characteristics that define a group of organisms and that did not exist in ancestral populations

Question 10

ancestral

Answer 10

characteristics that define a group of organisms that are due to shared ancestry

Question 11

convergent evolution

Answer 11

in biological evolution, a process by which unrelated populations develop similarities to one another due to similar function rather than shared ancestry

Question 12

continental drift

Answer 12

according to the theory of plate tectonics, the movement of continents embedded in underlying plates on the earth’s surface in relation to one another over the history of life on earth

Question 13

adaptive radiation

Answer 13

rapid diversification of an evolving population as it adapts to a variety of available niches

Question 14

preadapted

Answer 14

possessing characteristics that, by chance, are advantageous in future environmental conditions

Question 15

homeotherm

Answer 15

an animal that maintains a relatively constant body temperature despite environmental fluctuations

Question 16

isotherm

Answer 16

an animal whose body temperature rises or falls according to the temperature of the surrounding environment

Question 17

k-selected

Answer 17

reproduction involving the production of relatively few off-spring with high parental investment in each

Question 18

r-selected

Answer 18

reproduction involving the production of large numbers of offspring with relatively low parental investment in each

Question 19

arboreal hypothesis

Answer 19

a theory for primate evolution that proposes that life in the trees was responsible for enhances visual acuity and manual dexterity in primates

Question 20

visual predation hypothesis

Answer 20

a theory for primate evolution that proposes that hunting behavior in tree-dwelling primates was responsible for their enhanced visual acuity and manual dexterity

Question 21

molecular clock

Answer 21

the hypothesis that dates divergences among related species can be calculated through an examination of the genetic mutations that have accrued since the divergence