Evolution & Natural Selection

Front

What are vestigial structures?

Back

Body parts that have lost their original function.

Front

What are homologous structures?

Back

Body parts of organisms that are the same in structure and position but different in function and shared by a common ancestor.

Front

Which rock layer contains the youngest fossils?

Back

The rock layer labeled 'F'.

Front

What is evolution?

Back

The change in traits over time in a population.

Front

What traits were selected for in whale ancestors?

Back

Traits that helped them move in water.

Front

What is natural selection?

Back

The process by which organisms better adapted to their environment tend to survive and produce more offspring.

Front

What is a mutation?

Back

A change in the DNA sequence that can lead to new traits.

Front

What are analogous structures?

Back

Body parts that have similar functions but different structures and do not share a common ancestor.

Front

What is the significance of fossils in evolution?

Back

Fossils provide evidence of how species have changed over time and can show transitional forms.

Front

What is the role of genetic variation in evolution?

Back

Genetic variation is essential for natural selection, as it provides the raw material for evolution.