Ecology Lecture 8 + 9

Question 1

Define: BIODIVERSITY

Answer 1

the VARIETY and VARIABILITY of LIFE on earth

Question 1

Define: ALPHA DIVERSITY

Answer 1

a QUANTIFICATION of the number of species in a given area

Question 2

List some pros and cons of ALPHA DIVERSITY

Answer 2

pros: simple, quick, intuitive
cons: no info on abundance, ignores species composition, SENSITIVE to SAMPLE SIZE

Question 3

List qualities of larger areas

Answer 3

MORE SPECIES RICHNESS
more ecological niches
more stable
more likely to be colonized
more sampling required

Question 4

Define: SPECIES POOL

Answer 4

SET of ALL SPECIES that could possibly occur in an area or HABITAT

Question 5

Define: the THEORY of ISLAND BIOGEOGRAPHY

Answer 5

1. new SPECIES COLONIZE islands from nearby areas
2. as MORE SPECIES COLONIZE, FEWER SPECIES DISPERSE to the island
3. as species accumulate, INTERACTIONS CAUSE EXTINCTION
4. number of species reaches an EQUILIBRIUM

applies to mountaintops, forest fragments, and habitat patches as well

Question 6

how does extinction correlate with island size?

Answer 6

big island = less extinction (less poisonous)
small island = more extinction (more poinsonus)

Question 7

What influences SPECIES RICHNESS?

Answer 7

species pools, colonization, local extinction

Question 8

Define: RELATIVE ABUNDANCE

Answer 8

a PROPORTION of the TOTAL INDIVIDUALS of a species. used to measure SPECIES EVENNESS.

Question 9

Define: RANK ABUNDANCE

Answer 9

a CURVE that depicts the DISTRIBUTION of INDIVIDUALS among species in a community. gives us a VISUAL ASSESSMENT of SPECIES EVENNESS.

Question 10

Define: SHANNON DIVERSITY INDEX

Answer 10

a measure of both SPECIES RICHNESS and RELATIVE ABUNDANCE.

Question 11

Define: GAMMA DIVERSITY

Answer 11

QUANTIFIES the TOTAL number of species ACROSS HABITATS

Question 12

Define: BETA DIVERSITY

Answer 12

QUANTIFIES the DIFFERENCE in the species COMPOSITION between habitats. measure of how DIFFERENT two habitats are.