extra material chapter 27

Question 1

symbiosis

Answer 1

species that have close ecological associations with eachother

Question 2

brood parasites

Answer 2

rely on others to raise their young i.e. canvasback ducks or brown headed cowbirds

Question 3

encounter rate

Answer 3

abundance of prey

Question 4

Shannons Index of Diversity vs Evenness Index and what they measure

Answer 4

Index of diversity: measures species richness and evenness
Shannons evenness index: calculates any species evenness

Question 5

ecological succession is influenced by what

Answer 5

species’ dispersal, maturation, and lifespan differences

Question 6

latitudinal effects

Answer 6

• differentiation in species distribution based on proximity to or from the equator

Latitudinal Effects:
- decline towards poles
- most in the tropics
1) stable tropical climate
- more generations per year
- faster evolution
- small seasonal changes = less migration

2) maintenance
- stable resources
- tropical climate which supports ecosystem

Question 7

Robert MacArthur and EO Wilson

Answer 7

• hypothesis: number of species governed by the give or take between 2 processes
  = equilibrium theory of island biogeography
• number of species is constant

ISLANDS NEAR MAINLAND
- will have high immigration rates because dispersing organisms are more likely to arrive at islands close to point of departure
- number of species on island equals an increased extinction rate

Question 8

role of the wrasse, cod, and cleaner fish in the mutualistic relationship

Answer 8

wrasse: removes and eats ectoparasites

cod: being cleaned of parasites

cleaner fish: food

Question 9

defence mechanisms

Answer 9

1) size
2) external vigilance [alert]
3) camouflage
4) evasive action: thwart attack
5) impossible 2 attack: spines + armour
6) chemical signals
7) warnings [aposematic]
8) mimicry

Question 10

Allen Keast and honeyeater study

Answer 10

• 2 sympatric species fed in a wider range of situations than when you have 6 in the same area

Question 11

transboundary park

Answer 11

acknowledge differences in political and biological boundaries

Question 12

nearer islands:

Answer 12

• higher species richness on nearer islands because of its easier colonization

Question 13

larger islands:

Answer 13

• increased number of species because higher immigration rates and lower extinction rates
• confirmed by Amy Schoener w/ marine organisms study
• confirmed by Daniel Simberloff and EO Wilson with insects at Florida Keys

Question 14

Mangrove trees

Answer 14

• Daniel simberloff and EO Wilson study
• trees with canopies grew in shallow water and are isolated
• eliminated all the arthropods

RESULTS:
- rapidly recolonized
- decline in species riches
- species composition kept changing

Question 15

what type of community disturbance causes species richness to be the highest

Answer 15

intermediate frequency and severe intensity

Intermediate disturbance → balance between colonizers and competitors, allowing coexistence and higher diversity

Question 16

do both sympatric and allopatric species experience character displacement

Answer 16

• no, only sympatric species do because they have the pressure to look more different whereas allopatric species don’t [allopatric species look more similar because there is a lack of pressure to differentiate]
• done in sympatric to reduce competition or avoid hybridization

Question 17

the number of species found on a large island is

Answer 17

greater than the ones found on a smaller island

Question 18

a niche is essentially

Answer 18

the role an organism has in its environment

Question 19

fixed action pattern

Answer 19

sequence of innate, unchangeable behaviours that are once triggered by a specific stimulus and then run to completion without being stopped

Question 20

behavioural ecology refers to

Answer 20

how environmental factors can influence animal behaviour

Question 21

Species diversity reflects:

Answer 21

1. species richness—how many diff types of species do you have 2. relative abundance—how many of each species do you have