3.4.5 Species and taxonomy

Question 1

What is phylogeny?

Answer 1

Phylogeny is the study of the evolutionary history of groups of organisms. It tells us who’s related to whom and how closely related they are.

Question 2

What is a taxon?

Answer 2

One of the eight levels of groups used to identify organisms.

Question 3

List the groups of the phylogenetic hierarchy in order, starting from domain.

Answer 3

• Domain
• Kingdom
• Phylum
• Class
• Order
• Family
• Genus
• Species

Question 4

How does courtship behaviour help to prevent interbreeding?

Answer 4

• Courtship behaviour is species specific.

- Only members of the same species will do and respond to that courtship behaviour.

Question 5

How is courtship behaviour used in classification?

Answer 5

The more closely related the species are, the more similar their courtship behaviour.

Question 6

Rarely, a brook trout and a brown trout are able to mate to produce offspring known as tiger trout. Tiger trout are unable to reproduce.
Explain how you know that a brook trout and a brown trout are different species.
[1 mark]

Answer 6

They are unable to reproduce to give fertile offspring.