Lecture 4 - Interspecific Competition Flashcards
How does resource limitation exemplify negative feedback? [2]
When a populaton size expands, more resources are used.
This means less resources are available for further population growth, so the population declines.
Towards an ‘equilibrium’.
E.g. Clutch size
And vice versa.
Does density dependant negative feedback increase as population size increases? [1]
Yes
What 3 assumptions does the logical model of growth make? [3]
Density dependance is linear.
Population approache s K smoothly
K is constant
Why may a population surpass K? [1]
Because there is a time dealy before death rate increases or birth rate drops.
r and K are __________- level parameters. [1]
r and K are population- level parameters. [1]
Does selection happen on population level parameters or individual level? [1]
Individual leve parameters
Give two factors of a high density population. [2]
High competition
Low resources to the individual
Give four traits associated with high density. [4]
Large, few offspring (trade-off)
Delayed reproduction
Large sized
Long=lived
Give three traits associated with low density. [3]
Many small offspring.
Early reproduction.
Small, short-lived.
Lotka-Volkerra 1935. How do P. aurelia and P.caudatum interact when grown in a mixed population? [2]
P. aurelia K is reduced, however P. caudatum population falls dramatically possibly to extinction.
What is the Competitive exclusion principle? [1]
A suggestion by Gauss, that no two species can share the same resource and co-exist.
*Occupying same niche
What does a fundamental niche take into account? [3]
The intrinsic requirements of a species on its own.
Physiological and ecological limits.
Biotic limits.
What is the realised niche? [1]
When other species are considered within the niche.