Biological diversity is the wealth of life on earth. It refers to the millions of plants, animals, and micro-organisms, their genes and the relationships they build into the living environment. The total number of species plus all the genes they have is often referred to as the "worlds germplasm". Biodiversity is more than the sum of all the germplasm.

Biodiversity is the variety of ecological functions performed by nature. It is the variety of things that species do to keep the earth alive and healthy -- recycling nutrients, moderating the water cycle and climate, building soil, pollinating plants, maintaining habitats or homes for other species, and so on. Biodiversity is essential to the health of the planet and to yours.

Biodiversity is the variety of species and bigger biological groups like families or orders -- invisible bacteria, fish, mushrooms, diatoms, whales, weevils, snakes, lichens, frogs, mosquitoes, rats, and so on. It is the variety of genes or "blueprints" contained within and between species such as wheat or molluscs or algae.

The total diversity of life is difficult to estimate. Almost 1.5 million species have been given formal names. Further, there are estimated to be between 3- 5 million species alive today. Recent studies suggest that the true total may be ten times more - perhaps up to 50 million species.