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Name _____________________________ Period ______________ Date ___________________

Unit 6: Biodiversity & Conservation (Ch.7)

Biodiversity

• Describes the __________________ across all levels of _______________ organization

• Includes three types:

1) Genetic diversity: Differences in ___________________________________________

• Within a species, organisms have genetic differences

• In general, species with more genetic diversity have better chances of survival

2) Species diversity: Variety of _____________ in a given ________

• Easiest to visualize & ________________________________

3) Ecosystem diversity: Variety of ____________, ___________________, or communities in an area

• Ex. A seashore with rocky and sandy beaches, forested cliffs and ocean water has more biodiversity than the same area of farmland

_______________________ _____________________________ _____________________

Species Diversity – Classification

• Taxonomists classify species based on physical ________________ , ___________ makeup and ability to mate and produce ______________ offspring.

• Organisms are placed into a hierarchy of taxonomic groups:

• Domain• Kingdom• Phylum• Class• Order• Family• Genus • Species

• The more taxonomic levels two organisms have in common, the ___________________________ they are

• Taxonomic groups reflect _______________ relationships among species.

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• Below the species level, organisms may fall into________________—populations with genetically based characteristics that differ area to area.

Biodiversity Distribution

• Species are ____________ distributed among taxonomic groups.

• Even though _________ are small in size, there are ________ known species of insect than any other group.

• Scientists have identified and described ________________ species but estimate there are between ________________ species on Earth.

• Why?

• ________________________________________________

• ________________________________________________

• ________________________________________________

• Species are not evenly distributed ___________

• Latitudinal Gradient - there is an increase in species richness towards the ___________.

Benefits of Biodiversity

• _______________________ - valuable processes provided by intact ecosystems.

• Biodiversity enables services such as:

1) ___________________________________________

2) ___________________________________________

3) ___________________________________________

• High ________________ increases ____________ of communities and ecosystems, enabling them to perform services.

• Stable ecosystems are resistant and resilient.

• Resistant: Resist environmental change without ____________ function

• Resilient: Affected by change, but ______________________ and regain function

Agriculture

1) Wild strains are _____________ with related crops to transfer beneficial traits.

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• Ex. Corn that is disease resistant is cross-bred with normal corn to make a disease resistant hybrid (___________ diversity)

2) New plants are constantly being ______________ that have the potential for widespread use.

• Ex. Babassu palm used for vegetable oil (_____________ diversity)

Medicine

• Organisms contain compounds that are useful for ____________________.

• Of the 150 most prescribed drugs in the United States, _______ originated in __________.

• Ex. Yew tree, an original source of Taxol, a cancer-fighting drug

Ecotourism

__________________________________ tourism is a source of income for many nations.

Extinction

• Extinction – occurs when the _____________________of a species on the ____________ dies

• Extirpation – disappearance of a species from a particular __________ but ___________________________ globally

• Background extinctions: Naturally occurring extinctions, occurring _______ species at a time

• Mass extinctions: Events when extinction rates _____________ the normal background rate

• There have been ______ mass extinctions in Earth’s history

• Each time more than ______ of all species have gone extinct

Biodiversity at Risk

• The current extinction rate is ____________ times greater than the natural background rate.

• In 2009, 1321 species in the U.S. were classified as endangered or threatened.

• Endangered: At serious risk of _______________

• Threatened: Likely to become __________________ soon through all or part of its range

• Living Planet Index: Summarizes ______________________ trends for certain terrestrial, freshwater, and marine species

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• The Living Planet Index fell by almost 30% between 1975 and 2005.

Causes of Biodiversity Loss

4 Primary Causes of Population Decline and Species Extinction:

1) __________________

2) __________________

3) __________________

4) __________________

Habitat Loss and Change

• ___________ cause of biodiversity loss

• Organisms, ______________________________, decline in population when the habitat changes.

• Ex. Clearing forests for logging or construction

• Habitat ___________________: Patches of _____________ habitat surrounded by ________________ habitat

• In general, _________ habitat fragments can support _________________ biodiversity than smaller fragments.

• Habitat change or destruction is the primary cause of population decline in more than ________ of threatened birds and mammals.

• A few species can benefit from human induced habitat changes.

• These species tend to be ______________ and can become _______.

Ex. ___________, __________________ & _____________.

Invasive Species

• Invasive species can ____________________________ native species.

• Increase rapidly, spread and displace native species.

Pollution

• Harmful chemicals and materials that make their way into habitats can __________ people and wildlife.

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• Ex. Heavy metals, fertilizers, pesticides and _____________.

Overharvesting

• Occasionally, species can be driven toward extinction when humans _________, ____________ or ___________ a species faster than it can replenish its population.

• Poaching (____________________________) is one reason that the Siberian tiger is at risk for extinction.

• The parts from one tiger can be sold in the black market for approximately ____________.

Climate Change

• ____________ becoming a factor in biodiversity loss

• Unlike the other factors, climate change will have a _______________________ effect on biodiversity.

Protecting Biodiversity

The Endangered Species Act

• __________ that protects biodiversity, passed in 1973

• Has 3 major parts:

1) Forbids _________________ and ____________ from harming listed species and habitats

2) Forbids _____________________ made from listed species

3) Requires U.S. Fish and Wildlife Service to maintain an ________________of endangered and threatened species, and to develop a __________________ for each listed species

Benefits

• Birds which were affected by ________ are no longer endangered

• Some species are still endangered but have stopped _______________ (40% of are now stable)

Costs

• While trying to save the northern spotted owl, many __________________________because timber harvesting was prohibited in their area.

• Landowners worry that use of _________________ might be restricted to protect an endangered species.

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International Cooperation

• Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES, 1975): Bans ___________________ trade in _________________of endangered species.

• Convention on Biological Diversity (1992): International treaty to conserve biodiversity and ensure its responsible _______________________

Single-Species Approaches to Conservation

1) Captive breeding programs: Raising and breeding organisms in controlled conditions, such as ______________________________

2) Species Survival Plan (SSP): Program to save individual species, includes: ________________________________________________

• Ex. Golden Lion Tamarins

• In the early 1970’s habitat fragmentation had decreased the number to ~______.

• Now there are nearly _____ in captivity & more than _____ have been released back into the wild.

3) Cloning: Inserting _______ from an endangered species into a cultured egg cell with its nucleus removed then implanting eggs into mothers of closely ____________________

• Most scientists __________________that this will prevent biodiversity loss since it does nothing to fix the issues such as ______________.

Ecosystem and Habitat Approaches

1) “Hotspot Approach” - focuses attention on areas where the __________________________________ can be protected with the ___________________.

• A Biodiversity Hotspot is an area that both supports an especially ________________of endemic species and in rapidly ______________________.

• Endemic – found ________________ in the world.

• Hotspots have:

• At least ________ plant species found nowhere else in the world

• Already lost ______ of their habitat as a result of __________ activity

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• The 34 biodiversity hotspots are home to 50% of Earth’s plant species and 42% of terrestrial vertebrate species.

2) Economic Approaches - Many conservation efforts today attempt to balance __________________________________ with the __________________________________________:

• Debt-for-nature swap: Conservation organizations raise money to pay off a ______________________in return for improved __________________________.

• Conservation concession: Conservation organizations _________________________________________, instead of _______________________.

3) Wildlife Corridors-Connect _____________________ enabling once-isolated populations to interbreed

• Interbreeding increases ____________________.

• There is a current proposal to complete a 5000 mile long corridor in southeast Asia to rejoin pieces of tiger habitat.

• Conservation biologists hope that a planned 250-km (150 mile) long corridor in Australia will enable the endangered southern _________________ to recover from population declines

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