Calculations

Question 1

How do you calculate the coefficient of inbreeding?

Answer 1

Step 1: Allele frequencies of both
alleles
A=(2xno.AA)+no.AB / Population size x 2
Repeat for B allele
(p+q should equal 1)

Step 2: Expected genotype frequencies
p^2, q^2,a nd 2pq

Step 3: Expected number of individuals
p^2 x population size
q^ x population size
2pq x population size

Step 4: coefficient of inbreeding
F=1- Hobserved/Hexpected

Outcome: Close to 1 means high inbreeding (self-fertilisation, no heterozygotes)
Close to 0 means low inbreeding (random mating)
0.5 moderate inbreeding (siblings),
0.25 mild inbreeding (cousins)

Question 2

Genotype Frequencies

Answer 2

aa = no.aa/total population
bb = no.bb/total population
ab = no.ab/total population

Question 3

Allele Frequencies

Answer 3

a = (no.aa x 2) + ab / total population x2

b = (no.bb x 2) + ab / total population x2

Question 4

Selection Coefficient

Answer 4

Highest fitness individual gets assigned W = 1

Fitness (W) for others = offspring no. / fittest individuals offspring no.

Selection coefficient (S) = 1-W

Outcome: higher S means a higher section against a particular individual or genotype.
The fittest genotype always has S=0 and W=1, less fit genotype has lower W and higher S.

Question 5

Hamiltons rule

Answer 5

Altruism will evolve if r x b > c

r - relatedness
b - benefit to recipient
c - cost to donor

(r x b - c > 0)