Topic 19

Question 1

Fitness require

Answer 1

• suitable environment conditions (abiotic factors)

- sufficient resources (acquire energy efficiently and appropriate quantities)

Question 2

Predation

Answer 2

individual of one species (predator) consumes all or part of a living individual of another species (prey). includes blood feeders (mosquito)

Question 3

Predation excludes …

Answer 3

decomposers or scavengers

Question 4

3 predation categories

Answer 4

• herbivory
• carnivory
• parasitism

Question 5

Herbivory

Answer 5

prey is plant or alga

Question 6

Carnivory

Answer 6

prey is an animal

Question 7

Parasitism

Answer 7

for those parasites the feed on host tissue

Question 8

Carnivorous plants

Answer 8

derive their nutrients but not energy from trapping and digesting prey. 630 species. attract prey species

Question 9

Active and passive trapping system of carnivorous plants

Answer 9

• snap traps
• bladders
• flypaper
• pitfalls
• lobster pots

Question 10

4 differences of herbivore and carnivore

Answer 10

• carnivore typically kills their prey, whereas this is not the case as often with herbivore
• animal tissues are higher in nitrogen than plant tissues and so have a higher nutritional value
• animals can hide and plants cannot
• carnivores are often generalists and herbivore are specialists

Question 11

Specialist

Answer 11

individual takes one or a few prey types

Question 12

Generalist

Answer 12

individual takes many prey types

Question 13

Preference

Answer 13

proportion of a prey type in the diet is higher than in the environment

Question 14

Preferences will depend on

Answer 14

• energy content of prey

- nutritional content of prey

Question 15

Preferences switches depend on

Answer 15

abundance of different prey types

Question 16

Prey switching

Answer 16

switching to increased consumption rates of a more abundant type that used to be abundant

Question 17

Profitability

Answer 17

net energy gained after energy is spent capturing and consuming the prey

Question 18

Search time

Answer 18

search efficiency for prey

Question 19

Handling time

Answer 19

time to pursue, subdue and ingest prey

Question 20

Increased search and handling time both operate to ..

Answer 20

reduce consumption rate of predators

Question 21

Increased size of population decreases ..

Answer 21

search time and in some cases handling time

Question 22

Passive and filter feeders functionally have a

Answer 22

handling time of 0

Question 23

In general consumption rates and prey population size have a ..

Answer 23

linear relationship until satiation

Question 24

At very low population sizes consumption rates will decrease disproportionally and..

Answer 24

• need to learn capture strategy
• prey switching hasn’t occurred
• refuges exist ** good test question

Question 25

Goal is to predict the ..

Answer 25

optimal foraging strategy under certain conditions

Question 26

2 assumptions of optical foraging theory

Answer 26

- foraging behavioural enhances fitness | - animals maximize net energy gain

Question 27

Foraging strategy

Answer 27

behavioural trait favoured by natural selection in the past

Question 28

Predators must expand energy too

Answer 28

obtain prey

Question 29

Energy lost vs energy gain

Answer 29

searching and handling time vs consumption

Question 30

Diet model for specialist

Answer 30

-energy lost searching (consume more profitable prey)

Question 31

Diet model for generalist

Answer 31

-consume less profitable prey (low energy searching)

Question 32

2 diet model strategies have similar ..

Answer 32

net energy gain under different environmental conditions

Question 33

Diet model predicts that

Answer 33

- search time >> handling time =generalist (raccoon) | - if handling time >> search time =specialist (lion)

Question 34

Optimal foraging theory underlying model assumptions

Answer 34

- predators know everything about their foraging environment - predators perform complex mathematic to determine the profitabilities of a variety of prey types

Question 35

Model predicts that ..

Answer 35

individuals that approach the optimal strategy will have higher fitness.

Question 36

Predators may use..

Answer 36

general rules (take less profitable prey type after searching for a fixed amount of time)

Question 37

Predators may not maximize ..

Answer 37

net energy gain (take less profitable prey type with a specific dietary requirement)

Question 38

Predators may minimize their own..

Answer 38

risk of predation (take less profitable prey type to avoid foraging near a predator)

Question 39

Marginal value theorem

Answer 39

- Works off habitat patch concept - A foraging animal should leave a patch when consumption rates drop below the average for the range - Giving up time–the point at which consumption rates become average and to maximize energy gain the animal should leave the patch - Heavily influenced by distance between patches