What Is Biodiversity?
Biodiversity
• Biological diversity
• The number of different species in a given
area
• Number of known species: about 1.7 million
• Estimated total: greater than 10 million
Levels of Biodiversity
Species diversity
The number of different species in an area
Most often what is meant by “biodiversity”
Ecosystem diversity The variety of habitats, communities, and
ecological processes within and between
ecosystems
Genetic diversity
All the different genes contained within all
members of a population
Benefits of Biodiversity
• Species Are Connected to Ecosystems
– Every species is probably dependent on or
depended upon by at least one other species
– Keystone species: a species that is critical to the
functioning of the ecosystem in which it lives
because it affects the survival and abundance of
many other species in its community
Benefits of Biodiversity
• Species and Population Survival
– Genetic diversity is critical for survival
– Increases the chance that some members will
survive environmental change
– When a population shrinks, its genetic diversity
decreases
Benefits of Biodiversity
• Medical, Industrial, and Agricultural Uses
– Food, clothing, shelter, medicine
– ¼ of the drugs prescribed in the US are derived
from plants
– Antibiotics from chemicals found in fungi
– Undiscovered and poorly studied species
represent a source of potential products
– Food crops
• Most new crops: hybrids (from combining genetic
material from more than one population)
Benefits of Biodiversity
• Ethics, Aesthetics, and Recreation
– Do species and ecosystems have a right to exist
whether or not they have any value?
– Keeping pets, camping, picking wildflowers,
watching wildlife
– Ecotourism: a form of tourism that supports the
conservation and sustainable development of
ecologically unique areas