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Flashcards in Ecological Concepts Deck (18)
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1
Q

Who proposed island biogeography and when?

A

MacArthur and Wilson, 1963

2
Q

What are the two patterns of island biogeography?

A

Large islands have more species than small islands

Near islands have more species than far islands

3
Q

What are the two processes of island biogeography?

A

The farther the island, the slower the immigration rate

Extinction rate is higher on small islands

4
Q

What provides the source of immigrants for the islands?

A

The species look on the mainland

5
Q

How do you work out the equilibrium number of species on an equilibrium model of fauna?

A

Draw the immigration of new species curve on one side and the species extinction on the other side

Where the lines cross on the graph is where there is equilibrium

6
Q

What is countryside biogeography?

A

Where the edges around the habitat can be occupied by other species, rather than being surrounded by an inhospitable sea

7
Q

What types of islands are there?

A

Oceanic islands e.g Seychelles

Land bridge islands e.g Britain

Habitat islands e.g forest patches surrounded by farmland

8
Q

What is a meta population?

A

A set of local populations occupying various habitat patches and connected to one-another by the movement of individuals among them

9
Q

Give an example of a forest generalist that can occupy the forest edge and one that can’t:

A

Tupaia longpipes are a core forest species- won’t occupy edge

Muntjak deer are generalists and can occupy the whole forest

10
Q

What is the theory of drivers and passengers and who came up with it?

A

Removing drivers causes a cascade effect

But loss of passengers leads to little change in the rest of the ecosystem

Walker 1992

11
Q

What is the rivet popping hypothesis and who came up with it?

A

Species are rivets holding together a complex machine

All species make a contribution to ecosystem functioning

Ehrlich and Ehrlich 1981

12
Q

What is the insurance hypothesis and who came up with it?

A

Increasing biodiversity insures ecosystems against declines in their functioning

Yachi and Loreau 1999

13
Q

What are the three types of positive relationships between species richness and ecosystem functioning?

A

Redundancy, linear and idiosyncratic

14
Q

What is the idiosyncratic hypothesis?

A

The magnitude and direction of changes are unpredictable, as the role of species is complex and varied

The sequence in which species are removed matters

15
Q

What can ecological resilience be defined as?

A

The capacity of an ecosystem to absorb disturbance without shifting to an alternative state and losing function and services

16
Q

What happens if you pass the tipping point of resilience?

A

It leads to a completely different ecosystem state

17
Q

What is social ecological resilience?

A

The whole ecological resilience including humans

18
Q

What is the definition of minimum viable population?

A

The smallest size required for a population or species to have a predetermined probability of persistence for a given length of time