Evolutionary Ecology - LEC3

Question 1

Central ecological premises:

Answer 1

1. Environments/resources are finite
2. Best suited to the environment (more fit) will leave more offspring
3. More variable environments show higher diversity of organisms

Question 2

Robert MacArthur

Answer 2

• Niche theory/ Island biogeography (with E.O Wilson/r &K selection
• founded field of theoretical ecology

Question 3

E.O Wilson

Answer 3

-Island biogeography (with MacArthur

Question 4

Island Biogeography 1967

Answer 4

• habitat fragmentation
• species abundance curves
• species-area curves conclude that larger islands can support larger n.o of species
• area
• degree of isolation
• species equilibrium (immigration vs extinction)

Question 5

Species equilibrium

Answer 5

Log of no of species should increase with area more rapidly on distant islands than on close islands
-decrease more rapidly with distance on small than large islands

Question 6

Metapopulation Theory

Answer 6

Richard Levins 1969; Ilka Hanski 1982)

• eco-evolutionary processes
• differences in dispersal ability due to genetics balanced by host specialisation and reproduction
• integration allows identification of mechanisms rather than just patterns

Question 7

Serengeti-Mara Ecosystem

Answer 7

• borders defined by annual wildebeest migrations
• keystone species
• vaccination in cattle lowered rinderpest disease in wildebeest
• disease became unsustainable (r0<1)
• wildebeest increased pop.
• change in ecosystem - fewer trees, grass
• change in vegetation altered habitat for vectors of diseases infecting other animals

Question 8

recommended further reading

Answer 8

• Hanski, I. 2011. Eco-evolu5onary spa5al dynamics in the Glanville fri5llary bu]erfly. Proceedings of the Na,onal Academy of Sciences 108: 14397-14404
• MacArthur, R.H. & Wilson, E.O. 1967. The Theory of Island Biogeography. Princeton University Press.