Lecture 5 - Interspecific competition

Question 1

Gause & Lotka - Volterra looked at …

Answer 1

exclusion

niche

Question 2

when do indvs compete

Answer 2

when resources limited

Question 3

what effect do we measure

Answer 3

change in pop growth rate caused by another population

Question 4

experiment (Gause)

Answer 4

assume resources shared and limited

evaluate with 2 species = growth (r), K, density dependence

separately = density dependence, K

add another species = new K, other heading for extinction

Question 5

competition exclusion principle (Gause)

Answer 5

1. no 2 species can share the same resource
2. can’t occupy the same niche
3. can’t coexist when identical needs of limited resource

Question 6

fundamental niche

Answer 6

requirements of species on its own
physiological/ecological limits (abiotic, weather)

biotic limits (food, habitat)

Question 7

realised niche

Answer 7

limits when other species present

Question 8

competition theory equation

Answer 8

dN1/dt = rN1 - rN²/K - aN1N2

pop -ve fb effect of N2 on N1
growth exponential ddp -ve fb
(N1) intra inter

Question 9

intraspecific equilibrium

Answer 9

indvs coexist
B=D
Pop growth rate = 0

Question 10

interspecific equilibrium

Answer 10

both species coexist
B=D
PGR = 0

Question 11

equation for a line

Lokta-volterra

Answer 11

N1 = K1 - a12 N2

K = intercept, intraspecific carrying capacity
a = gradient, interspecific, adjustment of carrying capacity