Lecture 11: Interspecific Interactions 1 Antagonism Flashcards
what is a community?
an assemblage of species living in close enough proximity for potential interaction
what are the emergent properties of communities
species diversity, trophic structure, stability over time
What are interspecific interactions, and what are the three main categories
interactions between species (antagonism, comensalism, mutualism)
What are the antagonistic interactions
1) competition (-/-)
2) predation (+/-)
3) herbivory (+/-)
4) parasitism (+/-)
When does “antagonism:
competition” occur
occurs when species compete
for a resource that limits survival
and reproduction.
resources must be in short supply
exploitative vs interference competition
exploitative: individuals deplete resources by
consuming or using them
interference: aggressive encounters among
individuals shape resource
access
competitive inclusion
occurs when there is strong competition, the local elimination of a competing species.When two species compete for the same limiting resource they cannot coexist permanently
ecological niche - can ecologically similar species coexist?
the sum of an organisms use of biotic and abiotic resources; the organisms ecological role
ecologically similar species can coexist in a community if there are one of more significant differences in their niches.
How do species coexist?
Spatial and Temporal resource partioning
define spatial resource partioning
when two competing species use same resources by occupying different areas or habitats within the range of occurence of the resource
define temporal resource partioning
two species
eliminate competition by
using the same resource at
different times
fundamental vs realized niche
fundamental: the niche potentially occupied by that species
realized: the niche tht is actually occupied by that species
symptary vs allopatry
in sympatry, ranges overlap and co-occur but in allopatry ranges DO NOT overlap
Interspecific competition can lead to (3 things)
1) competitive exclusion of one species by another
2) coexistence of species through resouce partioning
3) coexistence of species through character displacement where ranges overlap
predation vs scavenging
predation: kill live animals
scavengers: consume dead carcasses
startle response, misdirecection, mimicry are all examples of
adaptations
startle response is
eyespots on butterflies
misdirection is
false heads
mimicry is
the close resemblance of an organism (to mimic) to some different organism to benefit from the mistaken identity.
what is aposematic coloration
anti-preadtor adaptations where warning signal is associated with the unprofitability of a prey to potential predators
Batesian Mimicry
an unprotected species (mimic) evolves to look like a protected species
nonvenemous snake > mimics venemous snake
Mullerian Mimicry
a chemically protected species evolves to look like another protected species
can mimicry be used for predators to approach prey
YES
whast happens to growth rates if you avoid predators
growth rates would heavily decline, less resources
predator-prey interactions affect (3 things)
1) population dynamics of predator and prey
2) the characteristics of predator and prey
3) the growth rates of predator and prey bc avoidance has a cost
Plant adaptations to avoid herbivory
structural and chemical adaptations
- inclue both physiological and morphological adaptations
Parasitoids
- specal type of parasite
- always kill host
- adult stage is free living
- lay eggs in host
ecto vs endoparasite
ecto: external- surface of host
endo: internation- live inside of host
