Conservation Biology and Biodiversity
47.1 The Biodiversity Crisis
Human activity is the driving force behind the current biodiversity crisis, which is causing great species loss in a short time period.
Types of Biodiversity
Genetic diversity, ecosystem diversity, and human-derived diversity are measures of biodiversity that currently define life on earth.
Biodiversity Change through Geological Time
Biodiversity has been affected by five mass extinction periods, which greatly influenced speciation and extinction rates.
The Pleistocene Extinction
Biodiversity loss, especially the disappearance of megafauna, during the Pleistocene Extinction has been linked to the arrival of humans.
Human activities probably caused the Holocene mass extinctions; many methods have been employed to estimate these extinction rates.
47.2 The Importance of Biodiversity to Human Life
Maintaining biodiversity ultimately helps maintain of human health; many medicines are derived from plants and, recently, animal toxins.
Maintaining genetic biodiversity of wild species of our crops that are related to domesticated species ensures our continued food supply.
Wild Food Sources and Psychological and Moral Value
Overfishing leads to fishery extinctions, loss of a food source, and affects many other species in ways that may be impossible to predict.
47.3 Threats to Biodiversity
Through increased adoption of sustainable practices, we can save biodiversity, while reducing habitat loss and irresponsible land use.
Overharvesting threatens biodiversity because it degrades ecosystems by eliminating species of plants, animals, and other organisms.
Exotic species introduced into foreign ecosystems can threaten native species through competition for resources, predation, and disease.
The global warming trend is recognized as a major biodiversity threat, especially when combined with other threats such as habitat loss.
47.4 Preserving Biodiversity
Technology has matured to the point where we can begin cataloging the planet's species in accessible ways; DNA barcoding is one such method.
Changing Human Behavior
Human responses to climate change and species loss include national and international legal measures, as well as the creation of preserves.
Conservation in Preserves
The purpose of ecological restoration projects, such as wildlife and ecosystem preserves, is to return ecosystems to pre-disturbance states.