Island biogeography
Download
1 / 36

Island biogeography - PowerPoint PPT Presentation


  • 655 Views
  • Updated On :

Island biogeography. What controls the number of plant and animal species on this island?. Does size matter? Isolation? Habitat variation? Environmental history?. Island in the Bay of Fundy. Species - area relationships.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Island biogeography' - erika


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Island biogeography l.jpg
Island biogeography

What controls the number of plant and animal species on this island?

Does size matter?

Isolation?

Habitat variation?

Environmental history?

Island in the Bay of Fundy


Species area relationships l.jpg
Species - area relationships

Johann Reinhold Forster (1729-98) served as a botanist with Captain Cook. After exploring the islands of the southern Pacific he observed:

“Islands only produce a greater or

less number of species as their circumference is more or less

extensive”.

Small islands harbour fewer species.

The Forsters’ (father & son) collecting specimens in Tahiti


Species area relationships3 l.jpg
Species-area relationships

Arrhenius (1921) “Species and Area”

Gleason (1922) “On the relation between species and area”. Ecology, 3.

Gleason censused the plants in 240 1m2 plots in an aspen wood in northern Michigan. He found 27 species in total, with an average of 4 species per quadrat.


Species area relationships4 l.jpg
Species-area relationships

Preston (1962) “The canonical distribution of commonewss and rarity”. Ecology, 43.

Preston introduced the ‘Arrhenius equation’:

S = cAz

where S is number of species, A is plot area, and c and z are constants.



Variations in value of c l.jpg
Variations in value of c

e.g. insects

plants

e.g. mammals


Variations in the value of z l.jpg
Variations in the value of z

real

world

cases

(0.26-

0.33)






Macarthur and wilson s theory of equilibrium island biogeography 1967 l.jpg
MacArthur and Wilson’s“Theory of Equilibrium Island Biogeography” (1967)

= equilibrium species number




Galapagos plant diversity and microclimate area is a proxy for habitat variability l.jpg
Galapagos plant diversity and microclimate: area is a proxy for habitat variability

<300 m

>500 m



The effects of island distance l.jpg
The effects of island distance controlled by habitat variation?



Dispersal probability with island distance l.jpg
Dispersal probability with island distance controlled by habitat variation?



Real world variations l.jpg
Real-world variations distance from PNG


Testing the macarthur and wilson theory l.jpg
Testing the MacArthur and Wilson theory distance from PNG

A. Natural experiments - Krakatau/Rakata


Slide23 l.jpg
Bird and mammal distance from PNGdiversity on the remnant islands of Krakatau vs. the biodiversity of neighbouring islands

Rakata

remnants

neighbours

Rakata


Rakata bird colonization l.jpg
Rakata bird colonization distance from PNG

McArthur & Wilson’s equilibrium predictions from nearby islands:

30 bird species

40 yrs to equilibrium;

turnover: 1 species/yr.

?

Survey dates


Rakata plant colonization l.jpg
Rakata: distance from PNGplant colonization



Testing the theory artificial experiments i defaunation and colonization l.jpg
Testing the theory: distance from PNGartificial experimentsI: defaunation and colonization

Small mangrove islands in the Florida keys


Testing the theory artificial experiments ii colonization of artificial substrates l.jpg
Testing the theory: distance from PNGartificial experimentsII: colonization of artificial substrates

Fouling panels



Extending the theory l.jpg
Extending the theory distance from PNG

“Insularity is moreover a universal feature of biogeography. Many of the principles graphically displayed in the Galapagos Islands and other remote archipelagos apply in lesser or greater degree to all natural habitats”

e.g. mountain-top alpine areas; islands of trees at the arctic treeline, urban parks, lakes, bogs, desert oases, clearcuts, islands of fragmented habitat, and even individual rocks, plants, etc.


Lake and bog islands l.jpg
Lake and bog islands distance from PNG


Mountain islands l.jpg
Mountain islands distance from PNG

  • Distribution of alpine tundra ecosystems in BC; an archipelago formed by hundreds of ± discrete islands separated by forest and prairie in the neighbouring valleys.


Mountain islands33 l.jpg
Mountain islands distance from PNG


Vacant urban lots l.jpg
Vacant urban lots distance from PNG

Vacant urban lot,

Philadelphia

Crowe, L. M. 1979.Lots of weeds: insular phytogeography of vacant urban lots. J. Biogeography 6: 169-181.


Fragmented habitat islands l.jpg
Fragmented habitat islands distance from PNG

1830 1882

“the breakup of a large landmass into smaller units would necessarily lead to the extinction or local extermination of one or more species and the differential preservation of others”

Alphonse de Candolle, 1855

True for all habitats; e.g. Wisconsin woodlands

1902 1950


Urban parks breeding birds madrid spain l.jpg
Urban parks: distance from PNGbreeding birds, Madrid (Spain)


ad