Lecture 6-Niches and geographical range

Question 1

What are the four processes that affect species distribution (climate…)?

Answer 1

• movement of land masses
• effects of islands
• climate change
• modern human impacts

Question 2

How did movement of land masses affect species distribution?

Answer 2

-separated animals but can explain some distribution due to the break up of Gondwana

Question 3

How does the number and appearance of species differ on islands vs mainland?

Answer 3

• islands have fewer species than the nearest mainland
• species are often different
• dispersal ability is key to explaining island biotas
• species with wide dispersal= on islands

Question 4

What is convergent evolution observed on continents?

Answer 4

-species that look and behave similarly but are not closely related

Question 5

What is parallel evolution observed on continents?

Answer 5

-similarity of form among related groups

Question 6

Give an example of convergent evolution.

Answer 6

-wing of a bat and a bird

Question 7

Give an example of parallel evolution.

Answer 7

-marsupials and placentals= similar thing despite separation

Question 8

Can niches explain modern day distribution of species?

Answer 8

-yes, information on species’ niches couple with documented changes from the past can explain much of modern day distributions especially over large scales.

Question 9

Do habitable places contain all the species that could live there?

Answer 9

-no