Natural selection was Darwin’s brilliant hypothesis, that accounts for adaptations, features that appear “designed” to fit organisms to their environment.

TLS Online TPP Program

#Id: 9211

#XL - T Zoology

THE MAGNITUDE OF GENETIC DRIFT

n  = population size

pq=allelic frequency

sp2=variance in allelic frequency among the populations

TLS Online TPP Program

#Id: 9212

#XL - T Zoology

Loss of their original diversity per generation

=1/2n

Gain of their original diversity per generation

=1/2n 

Gain or Loss of their original diversity per generation

=1/4n

TLS Online TPP Program

#Id: 9213

#XL - T Zoology

Probability of being heterozygote in given population

H = 1 - 1/2N

TLS Online TPP Program

#Id: 9214

#XL - T Zoology

Effective population size(Ne)

Effective number of breeding adults in a population.

TLS Online TPP Program

#Id: 9215

#XL - T Zoology

Some factor determine Ne

1.Sex ratio.

2.Variation between individual in reproduction success.

3.Fluctuation in population size.

4.The age structure of the population.

5.Mating is random.

TLS Online TPP Program

#Id: 9216

#XL - T Zoology

Ne = Male + Female  (when both are equal)

Ne = 4 × n(male) × n(female)/n(male)+n(female) 

(When both unequal Ne is smaller than then sum of both)