Island Ecosystems

Question 1

What are the two criteria that defines an island?

Answer 1

• Sub-continental land

* Surrounded by water

Question 2

A peninsula is an island. T or F?

Answer 2

False

It is a strip of land that still links to a land mass in some way

Question 3

Are continents islands?

Answer 3

No.

Question 4

What is a group of islands called?

Answer 4

An archipelago

Question 5

What is the biggest island in the world?

Answer 5

Greenland

Question 6

What are the 3 main types of island?

Answer 6

• Continental island
• Continental fragment
• Oceanic Island - hot spots and island arcs

Question 7

What are the two types of oceanic island?

Answer 7

• island arcs

* hot spots

Question 8

What is a continental island?

Answer 8

Part of a continental lane mass but has water that surrounds it because the land mass is lower in some areas.

E.g. GB and Ireland are actually attached to Europe!

Question 9

What’s a continental fragment?

Answer 9

Fragments of the continent which have broken off due to geological processes

E.g NZ

Question 10

What are oceanic islands, what are the two types and what are these?

Answer 10

Oceanic islands are islands that have never been connected to a continent.

A hot spot is a hot spot of volcanic activity which causes weaknesses in the cracks which forms volcanic islands.

An island arc are long chains of volcanoes found along tectonic plate boundaries.

Question 11

Is species richness good or bad on islands and why?

Answer 11

Bad because not many species would have been there when it was formed and not many would have made it there

Question 12

Why are island generally cooler, wetter and less seasonal than mainland?

Answer 12

More influenced by the sea around them

Question 13

The ocean around islands provides ______ stability. E.g?

Answer 13

Climatic stability

E.g rain formations hitting mountains

Question 14

What is sweep stakes dispersal?

Answer 14

When individuals arrive on an island

Question 15

Sweepstake dispersal is _____ toward taxa because..

Answer 15

Biased towards taxa because birds can travel more easily than most mammals for example.

Question 16

What is it called when individuals arrive on an island via floating land mass or by flying?

Answer 16

Sweepstake dispersal

Question 17

What is reproductive isolation and what is the consequence of having a reproductively isolated species on an island?

Answer 17

Reproductive isolation is when individuals are no longer related to their original population on mainland. Occurs via geological processes or sweepstake dispersal to an island.

The consequence is that they become a subset of the population and are unable to reproduce with mainland population

Question 18

What is in-situ speciation?

Answer 18

Rapidly advancing evolutionary soeciation

Question 19

What is adaptive radiation?

Answer 19

When species that arrive on an island go through the taxon cycle.

Question 20

What is the taxon cycle?

Answer 20

When species become generalists because they take on a lot of resources and then because of competition they specialise in individual niches

E.g finches on Galápagos Islands

Question 21

What does the species area relationship assume?

Answer 21

The bigger the Island the more species

equation: S=cAz

Question 22

What is the equilibrium model?

Answer 22

No. Of species on an island is at equilibrium point depending on size of island, how isolated it is, how easy to become extinct and how easy it is for individuals to colonise

Question 23

Island communities tend to be a ______ of main land communities

Answer 23

Subset

Question 24

What is disharmony?

Answer 24

When there are key missing aspects of an ecosystem

Question 25

What is ecological release?

Answer 25

When disharmony causes species to change their ecological restraints and requirements due to a change in ecosystem

Question 26

Competition is greater or lesser when species have become successful generalists?

Answer 26

Greater

Question 27

What is a generalist species?

Answer 27

A species able to eat a variety of foods and adapt their behaviour and physiology to survive in different ecosystems and habitats

Question 28

Generalists become successful through adaptive ____ and the ____ cycle. This results in more or less competition?

Answer 28

Adaptive radiation

Taxon cycle

More competition

Question 29

What is a keystone species?

Answer 29

An organism that helps define an entire ecosystem. Without its keystone species, the ecosystem would be dramatically different or cease to exist altogether. (National geographic website)

Question 30

What is edemism?

Answer 30

A species that only exist in a defined geographic area

Question 31

What are exotic species?

Answer 31

Ones that have been introduced

Question 32

What is nanism?

Answer 32

Smaller species

Question 33

What is giantism?

Answer 33

Larger species

Question 34

Explain a couple of consequences of flightlessness

Answer 34

• increases isolation

* fitness benefit removed

Question 35

What are super generalists?

Answer 35

Species able to adapt to new and broad ecological environments because there are less constraints over which resources they can take advantage of

Question 36

What is K-selection?

Answer 36

A slow growing species that has a reduction in the abundance of offspring production and an increased parental investment

Question 37

What is a R-Species?

Answer 37

Fast colonisers that are fast reproducers with little parental investment

Question 38

What two things makes islands especially vulnerable?

Answer 38

• Endemic species

* evolutionary distinct species

Question 39

How can we conserve islands? Name a couple

Answer 39

• reduction or eradication of exotic species
• in-situ and ex-situ breeding programmes
• reductions in habitat loss and exploitation