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Endangered species

An endangered species is at risk of extinction. For example, the snow leopard and gorilla are endangered and may become extinct.

A species can become endangered for several reasons, including:

• the number of available habitats falls below a critical level
• the population of the species falls below a critical level

Biodiversity

Biodiversity means having as wide a range of different species in an ecosystem as possible. It is important to conserve the variety of living organisms on Earth. Not only do we have moral and cultural reasons for conserving endangered species, but conservation:

• maintains the future possibility that plant species might be identified for medicines
• keeps damage to food chains and food webs to a minimum
• protects our future food supply

Seedbanks

If a plant species is endangered and therefore close to extinction, it is important to take measures to conserve the species. Seed banks are a conservation measure for plants - they are buildings in which seeds are stored so that new plants may be grown in the future, even if naturally the plants are extinct. This will help to maintain biodiversity.

Seed banks are an example of a gene bank. Gene banks are increasingly being used to preserve genetic material for use in the future. A cryobank is another type of gene bank. Embryos, sperm or eggs are stored at very low temperatures in liquid nitrogen (which is at –196 °C). They can be thawed out later for use in breeding programmes.