Unit 4 Lecture 22

Question 1

What is niche partitioning and name an example

Answer 1

Coexisting species use resources in different ways
- different types of the same bird divide up where they nest/live in trees to prevent competition

Question 2

What is another species that does this

Answer 2

The Anolis lizards, they forage different parts of a tree/tree floor
- Niche partitioning reduces the competition coefficient in both scenarios which increases the chances of coexistence

Question 3

Explain niche partitioning in spiny mice in the rocky deserts

Answer 3

Two species are competing species whose geographic ranges overlap
- One species hunts at night while the other hunts during the day
- Snakes hunt during the day
- They did a study to see if the one that is nocturnal was removed, if the other that hunted during the day would switch to night, which is did
- This proves that species 1 is more dominant, and they do this to reduce overlap in their competition of hunting

Question 4

What is ecological sorting?

Answer 4

Only one species survive per niche (competitive exclusion)

Question 5

What is ecological character displacement?

Answer 5

Two species that compete diverge in trait to reduce niche overlap

Question 6

Give an example of character displacement

Answer 6

Galapagos finches
- When they are the only species on an island, they have very similar niches (same beak size)
- When they were placed on the same island, the medium ground fish shifts its beak to the right, and the small shifts its distribution to the left

Question 7

Explain the character displacement of the Anolic Caroline’s in Southeast US?

Answer 7

• There we lizards located in SE US, which was subject to an invasive species in the early 1900s that was a trunk-ground morph
• The OG lizards also like tree trunks uh oh
• Did a study to see the change in height the OG lizards would hang with and without the invasive species
• When the invasive species came, the OG shifted upwards

Question 8

Whats the definition of character displacement?

Answer 8

Process whereby niche partitioning evolves through natural selection favoring individuals of each species that overlap less with other species

Question 9

The phylogeny of anoles lizards told us what?

Answer 9

• Speciation happens when populations end up on different islands
• Speciation also happens within islands as populations adapt to different habitats

Question 10

What are ecological guilds?

Answer 10

Groups of coexisting species that partition a particular adaptive zone through competition

Question 11

Whats an example of an ecological guild?

Answer 11

Seed eating desert rodents