Homologous and Analogous structures

[sidzeman]

Really basic question but
What are homologous and analogous structures - i always get the 2 confused
and how do they both provide evidence for evolution 

[pikachu975]

Really basic question but
What are homologous and analogous structures - i always get the 2 confused
and how do they both provide evidence for evolution 

Homologous: Similar structure but different function, e.g. the pentadactyl limb. It shows how different environmental pressures led to the different uses of body parts by natural selection. This can be seen as divergent evolution.

Analogous: Similar function but different structure, e.g. wings on birds and insects are both for flying but they developed it independently in common environments. This can be seen as convergent evolution and another example is sharks and dolphins having streamlined bodies and a fin due to similar selective pressures and niches.

[sidzeman]

ahhh great thank you