Lecture 12: Communities: Species interactions

Question 1

define community

Answer 1

All populations of species living together in a particular area.

Question 2

All organisms that do not photosynthesize ________, and all organisms are at risk of being eaten.

Answer 2

must eat other organisms

Question 3

predator-prey interactions

Answer 3

Resource species killed by interaction and consumption is from the outside in

Question 4

parasitoid-host interaction

Answer 4

resource species killed by interaction and consumption is from the inside out

Question 5

herbivore-plant interaction

Answer 5

Resource species is an “autotroph” and is partially consumed but usually survives

Question 6

parasite-host interaction

Answer 6

Resource species is an animal and is partially consumed by another animal but usually survives

Question 7

pathogen-host

Answer 7

resource species is partially consumed by a microbe that causes disease in the host

Question 8

how are species interactions dynamic

Answer 8

• Any particular interaction may shift category in the lifetime of individuals via development or over evolutionary time
• Duration of any given interaction can vary greatly

Question 9

species interaction - what is in a feedback loop

Answer 9

• outcome of community interactions
• evolution of the characteristics of interacting species

Question 10

explain the feedback loop of species interactions

Answer 10

• Community interactions are not static over time.
• Traits of species are evolving in direct response to community context
• community interactions can exert strong selection
• Adaptation can then shift the context and balance of community interactions, altering the outcome
• Adaptation can reinforce or destabilize interactions

Question 11

what do abiotic factors favor

Answer 11

static or convergent adaptations for “fitting in” with the environment - typically forms of environmental tolerance.

Question 12

what do biotic factors favor

Answer 12

diverse adaptations for “escaping” interactions with other species

Question 13

what species interactions select for mutual adaptations in the participating species.

Answer 13

All species interactions except commensalism

Question 14

define coevolution

Answer 14

• The reciprocal evolution in two or more interacting species with adaptations selected by their interaction
• an extremely widespread process

Question 15

what represents antagonistic coevolution

Answer 15

evolutionarily coupled consumer-resource interactions

Question 16

define evolutionary arms race

Answer 16

iterative escalation of resource and
consumer adaptations to each other.

Question 17

is evolutionary arms race a runaway process

Answer 17

• no, they frequently achieve an evolutionary stable state
• ultimately, adaptations in both species will be constrained

Question 18

define crypsis

Answer 18

The evolution of a camouflaged appearance in resting position

Question 19

how can behaviors enhance crypsis

Answer 19

by copying the shape and the movement of the surface against which the organism is camouflaged

Question 20

crypsis as a adaptive solution for prey

Answer 20

can be used by palatable prey to escape detection by predators

Question 21

crypsis as a adaptive solution for predators

Answer 21

can be used by predators to escape detection as they hunt palatable prey

Question 22

define warning coloration

Answer 22

• an adaptive solution in unpalatable species
• aposematism

Question 23

define aposematism

Answer 23

• an adaptation to advertise chemical defense
• not all chemically defended organisms have also evolved warning coloration

Question 24

what can a similar warning coloration do

Answer 24

evolve across a broad range of species, partly because they more quickly exploit existing aversions in predators

Question 25

players of mimicry - mimic

Answer 25

The species who’s appearance and behavior are being shaped by natural selection

Question 26

players of mimicry - model

Answer 26

the species that is being copied

Question 27

players of mimicry - dupe

Answer 27

the one being fooled

Question 28

Batesian mimicry

Answer 28

the evolution of a resemblance between a palatable mimic species and an unpalatable model species

Question 29

Müllerian mimicry

Answer 29

the convergent evolution of unpalatable species to resemble each other - each species is both mimic and model

Question 30

mimicry - who are the dupes

Answer 30

Consumers are the dupes and agents of selection (when not duped) in both Batesian and Müllerian mimicry

Question 31

how is mimicry similar to crypsis

Answer 31

Mimicry exploits sensory limitations of the consumer

Question 32

how is mimicry different from crypsis

Answer 32

mimics are copying another organism that the consumer would normally avoid

Question 33

plant defenses

Answer 33

• low nutritional content causes herbivores to lose interest
• chemical defenses: “secondary compounds” that impact herbivore nutrition and health
• physical defenses

Question 34

define constitutive defenses

Answer 34

defense is present at all times, and include chemical defenses and physical defenses

Question 35

define induced defenses

Answer 35

defense is produced/activated by herbivore damage

Question 36

What do humans use plant chemical defenses for?

Answer 36

Medicine, stimulants, manufactured products, seasonings for food