Ch.16&19- Species diversity

Question 0

How many species are on Earth?

Answer 0

about 2 million described

• 4%vertebrates
• 75 inverebrates
• 18 plants
• 3 other

-estimated there are actually 5-30 million species on earth

Question 1

Biodiversity

Answer 1

A term used to describe the diversity of important ecological entities that span multiple spatial scales (genes, species, and communities)

Question 2

species richness and composition by latitude

Answer 2

-Lower latitudes have more species and more variation in composition

Question 3

Sampling effort

Answer 3

• Should start to see a plateau

- where researchers want to get because they don’t want to have to sample more

Question 4

How much should we sample?

Answer 4

Until we start to see a plateau

Question 5

Who should we sample?

Answer 5

An easy to find group or indicator taxa

Question 6

How do we collect our data?

Answer 6

standardized sampling: Can determine relative abundance

Question 7

lognormal distribution

Answer 7

rare->subordinate-> Dominant

Question 8

3 ways to measure community diversity

Answer 8

1) species richness
2) Species Evenness
3) Species diversity

Question 9

species richness

Answer 9

the number of species found in the community = S

Question 10

Species Evenness

Answer 10

• provides information on the commonness or rarity of species
• includes abundance of each species in the area

Question 11

Species diversity

Answer 11

-Measure combining both number of species and relative abundance (evenness)
-Lost of different indices of species diversity
~most common is the Shannon Index
~greater H’ value means greater diversity
-scientist use diversity indices to compare communities

Question 12

H’

Answer 12

-[sum (pi ln Pi)]

Question 13

Environmental Complexity

Answer 13

More environmental complexity = more species

-can include: vegetation, elevation, nutrient availability, hydrology, and more!

Question 14

Stability

Answer 14

the tendency of a community to remain the same in structure and function

Question 15

Resilience

Answer 15

the rate of recovery after a disturbance

Question 16

What are the consequences of biodiversity?

Answer 16

Diverse communities are more stable and more resilient

Question 17

Generally, more diverse communities perform more functions

Answer 17

Community functions include: nutrient cycling, carbon sequestration, purification of water, purification of air, pollination

Question 18

Complementarity Hypothesis:

Answer 18

as species richness increases, there will be a linear increases in community function (graph: increase linear )

Question 19

Redundancy hypothesis

Answer 19

There is an upper limit on the effect of richness on community function (starts to get redundant) (graph: levels off like a K and evens out no matter if yo add)

Question 20

Driver and passenger hypothesis

Answer 20

Strength of effect varies dramatically with species ( graph: like stair cases)

Question 21

D& P with overlap:

Answer 21

drivers and passengers will over lap in their functions (graph: stair case and starts to level off)