Practice Questions

1.What is meant by the term evolution?

Evolution is the change in inherited characteristics of a population over time.

2.Give two reasons why Darwin’s theory was not accepted at first.

1.It challenged religious beliefs (idea that God created all life)

2.There was not enough evidence at the time

3.A population of beetles shows variation in colour. Birds can easily see the green beetles but not the brown beetles. Explain how the population may change over time.

There is variation in the beetle population due to a mutation, with some being green and some brown.

The green beetles are more easily seen by birds, so they are more likely to be eaten.

The brown beetles are better camouflaged, so they are more likely to survive.

The surviving brown beetles reproduce and pass on the allele for brown colour to their offspring.

Over generations, more offspring will inherit the allele for  brown colour.

As a result, the proportion of brown beetles in the population increases and the population becomes mainly brown.