Life on Earth - Evolution

Question 1

What is evolution?

Answer 1

• the change in the frequency of a phenotype in a population over many generations.
• It is reliant on variation

Question 2

What is extinction?

Answer 2

Result of organisms that are unable to adapt to the changes that happen on earth, therefore killing off the species.

Question 3

Explain the process of evolution

Answer 3

1. Natural selection occurs due to selection pressures
2. Best adapted individuals survive to reproduce
3. the favourable alleles that gave them the selective advantage are passed on
4. The alleles then increase in frequency through the population.

Question 4

Define the term ‘selection pressure’ and give examples

Answer 4

• Situations where only those that best fit the niche survive.

EXAMPLES
* intense predation
* intense competition

Question 5

What happens when species produce more offspring than the environment can sustain?

Answer 5

The offspring are put into intense intraspecific competition when resources are scarce.