The Biodiversity CrisisThe Biodiversity Crisis

Chapter 55Chapter 55

Types of biodiversityTypes of biodiversity

Genetic diversity:Genetic diversity:• Genetic differences within a single Genetic differences within a single

population and among geographically population and among geographically separate populationsseparate populations

Species diversity:Species diversity:• All the different species on our planetAll the different species on our planet

Ecosystem diversity:Ecosystem diversity:• The variety of interactions within and The variety of interactions within and

among Earth’s different ecosystemsamong Earth’s different ecosystems

Loss of biodiversityLoss of biodiversity

Extinction is a natural biological processExtinction is a natural biological process The rate of extinction is now 50-500 times The rate of extinction is now 50-500 times

the natural ratethe natural rate Other mass extinctions have occurred in Other mass extinctions have occurred in

Earth’s history Earth’s history This one is different in that it is:This one is different in that it is:

• due to human activitiesdue to human activities• compressed into a short time framecompressed into a short time frame• happening much faster than new species happening much faster than new species

evolution can occur evolution can occur

Ways to protect biodiversityWays to protect biodiversity

Protection of habitatsProtection of habitats• Habitat loss/degradation is the number Habitat loss/degradation is the number

one cause of threatened and one cause of threatened and endangered species in the U.S.endangered species in the U.S.

• Most of these species are ‘specialists’ – Most of these species are ‘specialists’ – species that occupy a narrow niche and species that occupy a narrow niche and have specific requirementshave specific requirements

• Habitat fragmentation makes it worseHabitat fragmentation makes it worse• Degradation of habitat through pollution Degradation of habitat through pollution

can also cause problemscan also cause problems

Ways to protect biodiversity…Ways to protect biodiversity…

Control invasive speciesControl invasive species• Biotic pollution introduces a non-native Biotic pollution introduces a non-native

species into an areaspecies into an area• It may prey on native species or It may prey on native species or

compete for food or habitatcompete for food or habitat• There may not be any natural controls in There may not be any natural controls in

that ecosystem – such as predators or that ecosystem – such as predators or disease – to limit their populationdisease – to limit their population

Ways to protect biodiversity…Ways to protect biodiversity…

Control other human activitiesControl other human activities• Pest eradication practicesPest eradication practices• OverhuntingOverhunting• PoachingPoaching• Commercial harvestingCommercial harvesting

Conservation BiologyConservation Biology

In situ conservationIn situ conservation• Preservation of ecosystemsPreservation of ecosystems• Biodiversity hotspots – areas in critical need of Biodiversity hotspots – areas in critical need of

helphelp• Restoration ecology – try to return an Restoration ecology – try to return an

ecosystem to it’s former stateecosystem to it’s former state Ex situ conservationEx situ conservation

• Preservation of the individual speciesPreservation of the individual species• Artificial inseminationArtificial insemination• Host motheringHost mothering

Legal protectionsLegal protections

U.S. Endangered Species ActU.S. Endangered Species Act• Species listed must be protectedSpecies listed must be protected• Species are listed without regard for Species are listed without regard for

economic impact of the listingeconomic impact of the listing Convention of International Trade in Convention of International Trade in

Endangered Species (CITES)Endangered Species (CITES)• Enforcement varies from country to Enforcement varies from country to

countrycountry