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Factors affecting the variety of species in an ecosystem


Biodiversity in an ecosystem

Biodiversity is the total variation that exists among all living things on Earth. In an ecosystem, biodiversity refers to the range of species that are present in the community. It is vitally important to have such variety to support the ecosystem and continue to let it flourish.

Explain the adaptations to a species habitat and niche

A habitat is the place where an organism lives and the niche is the species' role in the ecosystem. This refers to the whole way of life and includes the use that it makes of the resources in its environment.

An adaptation is an inherited characteristic that makes an organism well suited to its environment.


This viper’s outer skin has adapted to its surroundings. The snake’s use of camouflage is of survival value. This adaptation will protect the snake from being seen by predators.

Examples of adaptation

Desert plants:

A desert is a habitat where the conditions are extremely dry and the soil lacks water.

Cacti in a desert

A desert plant is able to survive in this harsh habitat due to the following adaptations:

  • Spines – decreases the surface area of the leaf
  • Succulent tissues – these are fleshy and store water
  • Long, deep roots – to reach water supplies

Darwin’s finches:

Charles Darwin visited the Galapagos Islands in 1835 where he discovered 13 different species of finches. The finches varied in size of beak and shape. This adaptation allowed the finches to pick and find suitable food from their habitat; it is of survival value to these birds.

Differently shaped finch skulls

In a stable ecosystem where the species are adapting to their surroundings, a wide variety of species can last for a long time as small changes won’t affect the entire ecosystem.

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