Lecture 24

Question 1

What is an Allee effect?

Answer 1

Very small population have decreased reproductive rates, or survival and are in danger of extinction

Question 2

3 causes?

Answer 2

1) Inbreeding - likely increased in small population (reduced fitness and survival)
2) Strange Sex Ratio (more likely to have strange sex ratios, less males = no great)
3) Lack of encounters (large areas –> population density is lower)

Question 3

Frequency-dependent selection by predators

Answer 3

Apostatic selection
negative selection
when there is more a certain one, more likely to be eaten (fitness declines as frequency of the phenotype increases)

Question 4

Sexual selection

Answer 4

Male-Male competition:
strongest, most competitive
Female choice:
Ornamented males
courtship routine