COMPETITION II
I. Comparison of two populations with different population parameters.
A. Comparison of growth rates 'r'.
1. Both populations must utilize - be limited by - the same resource
2. The population with the largest intrinsic rate of increase should ultimately
dominate
3. In nature we see that this is not always the case
B. Comparison of competitive ability
1. Ability to obtain limiting resources independent of population growth rate
2. The population with the greatest ability to remove resources should dominate
C. The competitive exclusion principle
"Complete Competitors Cannot Coexist"
1. What does this mean?
2. Does it have any application in Nature?
II. The Logistic competition models - Lotka Volterra
equations
dN1 = r1N1 (K1 - N1 - 12N2)
dt
K1
dN2 = r2N2 (K2 - N2 - 21N1)
dt
K2
NOTE your book uses  for 12 and β for 21. This is not the general usage and so here I use
subscripts.
III. Graphical analyses - competition isoclines
Conditions for coexistence
IV. The concept of the niche
"An N-dimensional hypervolume"
V. Restatement of the competitive exclusion principle
"Two species cannot coexist if their niches overlap too much"
A. How much is too much?
B. How similar is too similar?
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