Related topics: species

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In the world of paleoecology, little has been known about the historical record of ecosystems in the West African highlands, especially with regard to glacial cycles amidst a shifting climate and their effects on species ...

Tasmanian tiger doomed long before humans came along

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The quiet loss of knowledge threatens indigenous communities

Most of the knowledge that indigenous communities in South America have about plants is not written down. Now, ecologists at the University of Zurich have analyzed comprehensive information about the services provided by ...

Global warming hits sea creatures hardest

Global warming has caused twice as many ocean-dwelling species as land-dwelling species to disappear from their habitats, a unique Rutgers-led study found.

In the Tree of Life, youth has its advantages

It's a question that has captivated naturalists for centuries: Why have some groups of organisms enjoyed incredibly diversity—like fish, birds, insects—while others have contained only a few species—like humans.

Fish diversity linked to Caribbean coral reef health

The health of coral reefs can be impacted as much by the diversity of fish that graze on them as by the amount of fish that do so, according to a new study by scientists at Bigelow Laboratory for Ocean Sciences. In the Science ...

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Species diversity

Species diversity is an index that incorporates the number of species in an area and also their relative abundance. It is generally a much more useful value than species richness.

The most common index of species diversity is a family of equations called Simpson's Diversity Index[1].

Here is one such example

D = (n / N)2

Where n is the total number of organisms of a particular species and N is the total number of organisms of all species.D is the value of diversity. It can range between 0 and 1, whre 1 is the richest an Ecosystem can possibly be.

Humans have a huge effect on species diversity; the main reasons are: - Destruction, Modification, and/or Fragmentation of Habitat - Introduction of Exotic Species - Overharvest - Global Climate Change

This text uses material from Wikipedia, licensed under CC BY-SA