Speciation and Patterns of Evolution

Question 1

What is speciation?

Answer 1

• Speciation is the process of forming a new species.
• Changes need to occur in the gene pool that make populations isolated.
• These changes usually arrive through mutations and these can form new
  adaptations.

Question 2

Patterns of Evolution

Answer 2

• Evolution has two different patterns which result in
  different adaptations over time.
• Selection pressures can have different or similar
  effects on species.
• The two patterns are divergent evolution and
  convergent evolution.

Question 3

Divergent Evolution

Answer 3

Numerous species develop from one common ancestor, becoming less and less alike over time.

Eg. Whale, Human

Question 4

Convergent Evolution

Answer 4

Numerous species that are not closely related but occupy similar habitats resemble each other. While they look the same, they are genetically very
different.

Eg. Bat, Falcon

Question 5

Analogous Structures

Answer 5

• Animal structures that perform similar functions
  but aren’t closely related.
  Examples:
• a fin of a shark (non-bony fish) and dolphin
  (mammal)
• a wing of a bird and a bat (mammal).
• Eyes of human and octopus

Question 6

Homologous Structures

Answer 6

• Animal structures that have evolved from a common ancestor but now have
  different uses.
• e.g. whale and human forearms.