28- global patterns of biodiversity

Question 1

what is the latitudinal diversity gradient?

Answer 1

biodiversity tends to be higher near the equator and lower close to the poles

Question 2

How do abiotic factors differ between the tropics and the tundra?

Answer 2

tropics:
high…
sunlight, temp, precipitation, long growing season
low disturbance
stable climate

tundra:
low…
sun, temp, precipitation, short growing season
high glacial disturbance
variable climate

Question 3

how does warm wet climate affect speciation?

Answer 3

high productivity

Question 4

what is primary productivity?

Answer 4

plant growth = rate of photosynthesis

Question 5

what is secondary productivity?

Answer 5

animal (consumer) growth

Question 6

what is the cradle hypothesis?

Answer 6

is a evolutionary hypothesis: explains how and why species have accumulated in the tropics through natural selection and speciation

Question 7

what is the museum hypothesis?

Answer 7

is an evolutionary hypothesis: explains how and why species have accumulated in the tropics through speciation over a ling period of time

Question 8

what is the productivity hypothesis?

Answer 8

is an ecological hypothesis: explains that the tropics are more diverse due to less competition

Question 9

what scale does climate determine species diversity?

Answer 9

on a global scale -> affects speciation and extinction