Original population Equal
frequency
of black
and white
alleles
Allele frequency
differs
New population increase
New population increase
Chance event reduces
population size
Chance event reduces
population size
1. The model shows a demonstration a student prepared
using black and white marbles to show how populations of
organisms can change. Which of the following concepts is
best illustrated by this demonstration?
A Evolution of a predatory species
B Genetic drift accompanying natural selection
C Environmentally induced genetic mutations
D Immunity from virulent microorganisms
A
B
C
D