module 12

Question 1

Biodiversity

Answer 1

measure of the different kinds of organisms in a region or other defined area

Question 2

species richness

Answer 2

the number of species in a region or specified area

Question 3

species diversity

Answer 3

is the number of species in the community and their relative abundances

Question 4

species evenness

Answer 4

the degree of equitability in the distribution of individuals among a group of species. maximum evenness is the same number of individuals among all species

Question 5

simpsons index of biodiversity

Answer 5

sometimes written as 1-d such that the most diverse regions are the close to 1

Question 6

phylogenetic diversity

Answer 6

an index that quantifies biodiversity while incorporating the phylogenetic differences in a sample

Question 7

species endemism

Answer 7

species that are unique to a geographic location; organisms that are indigenous to a given region are not endemic to it if they are also found elsewhere

Question 8

more energy =

Answer 8

more primary productivity = more niches

Question 9

species energy hypothesis

Answer 9

there is more energy (sunlight) in the tropics so more primary productivity; more niches, and more species

Question 10

climatic harshness hypothesis

Answer 10

tropical climate presents fewer stresses than temperate climate, so more species

Question 11

climatic stability hypothesis

Answer 11

tropical climate is more stable over time

Question 12

time and area hypothesis

Answer 12

most lineages originated in tropical environments throughout the cenozoic because the earth in the past was warmer, few lineages have been able to adapt to temperate regions

Question 13

diversification rate hypothesis

Answer 13

the rate of increase in diversity is greater in the tropics because of a higher speciation rate, lower extinction rate, or both.

Question 14

gilinksy and bamback

Answer 14

found that rate of origination within orders decreased over time, while the rate of extinction within orders increased over time

Question 15

stanley

Answer 15

suggests that speciation extinction rates are correlated because both are influenced by intrinsic features of the organism

Question 16

lineage through time plot

Answer 16

measure the rate of cladogenesis as a function of time, clades that diversify at a constant rate will have an approximately straight line in a lineage through time plot

Question 17

EO wilson definition of extinction

Answer 17

termination of any lineage of orgnaims from subspecies to species and higher taxonomic categories from genera to phyla, can be local, or total (global) in which all populations vanish

Question 18

what populations are more vulnerable to extinction?

Answer 18

small populations

Question 19

what is the minimum viable population size?

Answer 19

the point at which a smaller population becomes prone to extinction, typically 10s - 100s of individuals, related to species-area effects

Question 20

what percentage of species are extinct?

Answer 20

> 99.9%

Question 21

background extinction

Answer 21

the total sum of extinction lineages over time

Question 22

Van halen

Answer 22

provides evidence that the likelihood of species extinctin is independent of the age of the taxon

Question 23

Jablonski

Answer 23

the likelihood of species extinction is inversely proportional to the size of the species range

Question 24

Mass extinction

Answer 24

the sudden disappearance of a large number of species (60%) in a short period of time

Question 25

Raup

Answer 25

calculated the percentage of taxa that went extinct in each of the 1-myr intervals since the cambrian explosion

Question 26

Cretaceious-teriary mass extinction K-T(K-Pg)

Answer 26

(70%) species - all marine reptiles, dinosaurs went extinct, many mammals, birds, terrestrial reptiles, dramatic shift in vegetation (angiosperms pollen decreased; fern spores went up, plankton levels collapse)

Question 27

possible causes for mass extinctions

Answer 27

climate change, sea level changes, predation, epidemic disease, competition with other species, exotic external causes

Question 28

exotic causes

Answer 28

processes or phenomena that we do not typically experience

Question 29

volcanism

Answer 29

many volcanoes erupt at the same time

Question 30

exotic causes

Answer 30

processer or phenomena that we do not typically experience