Biodiversity and Conservation Exam

Topic 3 of Enviromental Systems and Societies: 3.1 - Biodiversity and Evolution, 3.2 - Human Impacts on Evolution, and 3.3 - Conservation and Regeneration of  Biodiversity

Genetic Biodiversity

• Is the total number of genetic characteristics of a specific species within a population.

• larger population = greater genetic diversity

Species Biodiversity

• Is the number of species or organisms per unit area found in different habitats of the planet.

• How many different species are there?

  • 1.75 million known

• Many more unknown

  • 5 – 50 million or more

Habitat Biodiversity

• Range of different habitat per unit are in an ecosystem or biome

  • (niches per unit area)

• If habitat diversity is conserved than this usually leads to the conservation of species and genetic diversity.

Biodiversity Hotspots

• These areas need emergency conservation attention

• Especially rich in endemic plant and animal species (found nowhere else in the world)

• They cover on 1.4% of world land area

Distribution of Biodiversity

• Richness: The number of species per sample is a measure of richness.

  • The more species present in a sample, the “richer” the sample.

• Evenness: A measure of the relative abundance of the different species making up the richness of an area.

Evolution

The cumulative and gradual change in the genetic characteristics of successive generations of a species

Natural Selection

The process where organism that are better adapted to their surrounding are more likely to survive and produce more offspring

Darwins Conclusion

• All species tend to over-reproduce

• This leas to competition for limited resources

• Species show variation

Speciation

The formation of one or more new species from the pre existing species is called 'Speciation'.

Geographic Isolation

forms are separated by land or water barriers that they are unable to cross

Ecological Isolation

the forms fail to meet because they live in different places within the same geographic region.

Temporal Isolation

the forms are active at different seasons or times of day.

Behavioral Isolation

When two populations are capable of interbreeding but don't since they have differences in reproductive strategies that involve behavior.

Plate Tectonics

This theory explains the movement of the Earth's plates and also explains the cause of earthquakes, volcanoes, oceanic trenches, mountain range formation, and many other geologic phenomenon.

Plate Tectonics

The movement of plates through different climatic zones allows new habitats to present themselves, and allow for different adaptations.

Background Extinction

Not fit for the environment. Typically, according to the fossil record, this rate is about 1 species per million per year, or about 10-100 per year. This range highlights the difficulty in predicting without a full account of species in existence. As a result, estimates vary widely.

Mass Extinction

More than ½ of the species extinct in 2 million years based on fossil record.

Natural Extinction Causes

• Volcanic Eruptions

• Drought

• Meteors

• Glaciers and ice age

• Competition and Predation

Human Extinction Causes

H - Habitat destruction and fragmentation

I - Introduced species

P - Pollution

P - Practices of agriculture

O - Over hunting

Tragedy of the Commons

Tension between the common good and the needs of the individual and how they can be in conflict.

Factors of Extinction Vulnerability

• Population size:

• Reduction in population size:

• Numbers of mature individuals:

• Geographic range and fragmentation:

• Quality of habitat:

Direct Benefit of Biodiversity

• Food Sources

• Natural Products

• These are the Provisioning Ecosystem Services

Indirect Benefit of Biodiversity

• Soil Aeration

• Fertilization and pollination of crops

• Soil and water resources protected by vegetation

• Climate is regulated by rainforest and vegetative cover

• Waste recycled by decomposers

• Scientific and educational value

• Biological Control Agents

• Value of what we don’t know...

• Human Health (antibiotics, cancer medications...)

• Human Rights –Indigenous tribes who rely on biodiversity

• Recreational- Cultural Ecosystem Services

• Ecotourism

• Ethical/ Intrinsic Value

• Biorights- Self Perpetuation- Systems healthy enough to succeed don’t need conservation

Prevention Biology

• Starts from an ecocentric viewpoint which values nature intrinsically

• Does not see nature as a resource to be exploited

Conservation Biology

• Advocate for a sustainable approach to the utilization of nature’s resources

• Look to manage the environment in a way that benefits humans and maintains long term sustainability

Species-based conservation

Focused on conserving species, but less interested in conserving the habitat the species resides in. 

Habitat Conservation

Focused on the protecting the entire habitat first, and species as a secondary focus.

CITES

The Convention on International Trade in Endangered Species of Wild Fauna and Flora

• CITES is an international agreement to address the threat to species presented by international trade.

Flagship Species

• Species based Conservation is also approached through the use of Flagship or Umbrella Species.

• These are typically the glamour species. The Polar Bear is a great example of the flagship species for Arctic conservation.

Keystone Species

• These are species which play a critical role in the maintenance of their ecosystem.

• The loss of these species has a much larger impact on the overall system than is proportional to their numbers and or biomass.

Ex Situ Conservation

Conservation strategies that involve the preservation of species outside their natural habitats, such as in zoos or botanical gardens.

In Situ Conseravtion

Conservation practices that take place within the natural habitat of species, aiming to protect and maintain biodiversity in situ.

Reserves and Ecotones

Areas managed for conservation, maintaining biodiversity by protecting distinct habitats where different ecosystems meet.