Species turnover on islands is generally low - The number of species on an island might remain the same, but the composition of the species should change continuously as new species colonize the island and others become extinct.

TLS Online TPP Program

#Id: 5723

#Unit 10. Ecological Principles

Species-Time Hypothesis 

Communities diversify, that is, gain species, with time

Temperate regions are less species-rich than tropical regions because they are younger and have only more recently recovered from glaciations and severe climatic disruption

TLS Online TPP Program

#Id: 5724

#Unit 10. Ecological Principles

TLS Online TPP Program

#Id: 5725

#Unit 10. Ecological Principles

The Species-Area Hypothesis Large areas contain more species than small areas because they can support larger populations and a greater range of habitats.

TLS Online TPP Program

#Id: 5726

#Unit 10. Ecological Principles

TLS Online TPP Program

#Id: 5727

#Unit 10. Ecological Principles

The Species-Energy Hypothesis

Available energy determines species richness.

Increased solar energy, together with an abundance of water, results in high productivity of plants.

TLS Online TPP Program

#Id: 5728

#Unit 10. Ecological Principles

The evapotranspiration rate is in turn influenced by the amount of solar energy and the amount of water in the ground.