Theory of Island Biogeography
Graphic by Sharon
What is the Theory of Island Biogeography?
Graphic by en.wikipedia.org
The Theory of Island Biogeography is a concept that explains the uneven distribution of species in different islands. An equilibrum is reached when the line representing immigration rate of new species and line representing the extinction rate of resident species intersects, indicating the number of species present, or the species richness on an island.
Variables that affect species richness are:
Hence,
Applications of Theory of Island Biogeography
Wildlife corridors are used as a conservation tool to increase connectivity between habitat islands. Wildlife corridors increases the movement of species between parks and nature reserves, hence increase species richness. Unfortunately, they also make it easier for the the spread of disease and pathogens between populations, which can result in greater extinction rates.
Graphic from straits times
In Singapore, an example of a wildlife corridor is Eco- Link @ BKE:
More about Eco- link @ BKE:
- It is the first overpass in Southeast Asia built specifically for wildlife.
- It aims to reestablish an ecological connection and balance between once separated habitats in the Central Catchment and Bukit Timah Nature Reserves. This allows wildlife to expand their habitat, and hence its survival chances.
Criticism
This theory gave rise to one of the most heated controversies in conservation history:
The Single Large Or Several Small (SLOSS) Debate
There were 2 camps:
that a single large land reserve would be more beneficial in terms of species richness and diversity than several smaller reserves
VS
that several smaller reserves will result in even more species, if the smaller reserves each contained unique species
Conclusion:
Much research was done in support for both stands, and it was concluded that the effectiveness of both types of reserves depends on the circumstances provided. Several small reserves seem to be more effective when a species has low extinction rates, while single large reserves seem to be more effective when a species has high extinction rates. In general, however, as the extinction rates of species are volatile and uncertain, scientists tend to prefer the integrity of a single large reserve.
His book on the Theory of Island Biogeography:
Graphic from amazon.co.uk
To find out what other books he has written,