CH 10 Ecology Exam 3

Competition

int btwn 2 or more indiv both req same limited resource, that when used or def by 1 indiv red the surv or repro of another indiv

→usually red Sx or Fx of BOTH indiv

Liebig’s law of minimum

most limited resource (aka limiting resource), which is spec limited resource that ultimately det the pop growth rate

Interference competition

direct interactions

indiv fight for acc to limit resources

→ can occ in both intErspecific and intrAspecific

ex/ allelopathy

Allelopathy

plant releases biochem that dir influences growth, surv, repro of other indiv

→can inc fire freq/intensity = red pot competitors

Exploitative competition

indirect interactions

aff others from acc resources by consuming them first

→food, water. sunlight

Ecological Niche

range of a/biotic conditions within which indiv of a spp can surv, grow, repro

ex/ what they eat (type, size, location), live (loc, clim), when active (day,night)

Competitive Exclusion Principle

2 spp cannot coexist indefinitely on same limiting resource (substantial niche overlap)

competitive exclusion of 1 spp when niche overlap substantially

inferior comp go locally extinct (extirpated)

coexistence via resource (niche) partitioning when niches overlap substantially

sim spp can coexist if share resources, niches no longer comp overlap

→Nat select drives comp spp intro diff patt of resource use = diff niches

Physical attribute

resource partitioning

→ choose part size, color, etc

Spatial attribute

resource partitioning

→choose resources occ in a specific location

Temporal attribute

resource partitioning

→ use resources only during a specific time

Physiological, morphological differences due to

adaptive evolution result in resource partitioning

Behavioral differentiation may be due to:

- adaptive evolution, and thus is NOT easily changed (IS fixed)(innate)

OR

- learned response, and thus IS easily changed (is NOT fixed)

Character displacement

type of resource part. that occ ONLY where 2 spp occ together

→ only true if the 2 spp differ morph/behaviorally when together

Logistic equation

intrAspecific comp red pop growth rate

→ as N approaches K, pop growth rate dec

Comp model

both IntrA and intEr comp red pop growth rate