Plant Animal Interactions

Question 1

define mutualism

Answer 1

both species benefit

Question 2

define commensalism

Answer 2

one benefits

no impact to other

Question 3

define predation

Answer 3

one benefits

one loses

Question 4

define amensalism

Answer 4

one loses

no impact

Question 5

define competition

Answer 5

neither win/lose

Question 6

most common species interaction?

Answer 6

plants and animals

Question 7

what are the 4 types of herbivory?

Answer 7

gazers
browsers
frugivores
granivores

Question 8

constraints of herbivory in N regions?

Answer 8

short growing season

• constrains plant growth/reproduction
• constrains herbivore growth and repro

Question 9

heavy exploitation of plant species by herbivores can…

Answer 9

• decrease abundance
• destroy insulating moss layers
• change plant communities

Question 10

benefits of herbivores?

Answer 10

• defecate, adding nutrients
• alter competition regimes btwn plants
• disperse seeds

Question 11

costs of herbivory?

Answer 11

complete defoliation

precludes reproduction

Question 12

muskox impacts on willow

Answer 12

main summer food source
-production of arctic willow +’vely affects muskox next year
vise versa

Question 13

What are producers limited by?

Answer 13

competition and resources

- not herbivory

Question 14

define trophic cascade

Answer 14

influence of producers or consumers on species that are 2+ trophic levels away

Question 15

define top-down control

Answer 15

influence on predators on relative abundance on lower trophic levels

Question 16

define bottom-up control

Answer 16

influence of producers on relative abundance of higher trophic levels

Question 17

hypotheses regarding why the world is green

Answer 17

Exploitation ecosystem hypothesis (EEH)

Question 18

Exploitation ecosystem hypothesis (EEH)

Answer 18

• effects of trophic cascades usually alternate by trophic level
• primary productivity determines the number of trophic levels in an ecosystem

Question 19

example of a trophic cascade

Answer 19

kelp, sea urchins, and predators in Alaska

Question 20

what determines the number of trophic levels?

Answer 20

productivity

Question 21

plant defence traits against herbivory

Answer 21

mechanical (toughness, spines, etc.)
chemical (alkaloids, phenolics, etc)
developmental/phenlogical

Question 22

types of plant defence based on production

- define

Answer 22

Constitutive: present irrespective of attack (thrones)
Induced: produced in response to the attack

Question 23

define co-evolution? how may this occur with herbivory?

Answer 23

evolution of 2+ interdependent species, each adapting to changes in the other

plants evolve defences–> herbivores evolve ways to overcome

Question 24

example of co-evolution (general)

Answer 24

newt develops toxins
predators more resistant will have advantage over predators w/o
only most toxic newts survive
predator evolves more resistance to toxins

Question 25

specific example of co-evoluation

Answer 25

crossbills and black spruce

-bill morphology and cone morphology

Question 26

define seed masting

Answer 26

the synchronous and highly variable production of seeds by a population of plants

Question 27

how does masting impact red squirrel life history response?

Answer 27

large litters
more yearlings breed
more offspring produces

Question 28

example of secondary plant metabolites

Answer 28

[increase] in Arctic willow during growing season

-more energy, nutrients, and productive investment

Question 29

example of mutualism within herbivory

Answer 29

minus and Clark’s nutcrcker

- dispersal of seeds through scatter hoarding

Question 30

why are oviposition sites probably limited in boreal forests?

Answer 30

closed canopies
seasonality
sever cold winters
tree spp mostly conifers (wind pollinated)

Question 31

are insects important in boreal regions?

Answer 31

previously thought no… more recently YES!

- plants have diversity of pollination strategies

Question 32

define entomophily
where is this most common?
example

Answer 32

pollination by insects
high arctic
Arctic rose

Question 33

common pollinators in high arctic

Answer 33

bees
mosquitoes
moths
wasps
beetles
flies

Question 34

percentage of bees/insects in NA compared to boreal region

Answer 34

4. 3% NA
5. 4% Boreal
   - mostly bumblebees bc generalists, social (thermoregulate)

Question 35

What is the most important/abundance pollinator in Sweden?

Answer 35

Diptera