Science Man and His Environment/Biodiversity

Definitions

 * Biodiversity : The variety of living things in a region

There are three kinds of biodiversity:
 * Genetic Diversity : The variation in genetic makeup within a population
 * Species Diversity : The number of species within an area
 * Ecosystem (or Ecological) Diversity : The number of different ecosystems in an area

Biomes

 * Biomes : The world's major communities classified according to the predominant vegetation

WWF Classification
The WWF has identified 14 biomes:


 * Tropical and subtropical moist broadleaf forests
 * Tropical and subtropical dry broadleaf forests
 * Tropical and subtropical coniferous forests
 * Temperate broadleaf and mixed forests
 * Temperate coniferous forests
 * Boreal forests/taiga
 * Tropical and subtropical savannas
 * Temperate grasslands
 * Flooded grasslands
 * Montane grasslands
 * Tundra
 * Mediterranean forests
 * Deserts
 * Mangrove

There are also 13 freshwater biomes and 5 marine biomes

WWF further divides the Earth into 867 terrestrial and 450 freshwater ecoregions.



for a larger and more readable version go here

Darwin's Finches

 * Darwin's Finches

Did you know?
Can you answer the following questions? Click on the link to find out.


 * What is the fastest land animal? Answer video
 * What is the fastest animal? Answer
 * What is the slowest animal? Answer
 * What is the largest animal ever to have lived? Answer
 * What is the smallest vertebrate? Answer
 * What is the oldest living thing and how old is it? Answer

Ecosystem Services
Ecosystem services are the benefits provided by ecosystems that contribute to making human life both possible and worth living.

Biodiversity Loss Threatens Human Well-Being (see especially Box 1 near bottom of article)



Case Study: Honey Bees

 * Bees, Bees, Bees


 * Honey Bees


 * List of crop plants pollinated by bees


 * Colony Collapse Disorder

Invasive species
A serious problem is invasive species - plants and animals not native to an area and disrupt the ecosystem.


 * Cane toad
 * Cane toads in Australia


 * Zebra mussel
 * Zebra mussel
 * Zebra mussel in water pipe


 * 100 of the World's Worst Invasive Alien Species

Endangered Species
Endangered species Those species which are at risk of extinction.

There is an international list of species called the Red List which is maintained by the International Union of Conservationists (IUCN). The list rates the species from least concerned to critically endangered.

Also maintained is the Convention on International Trade in Endangered Species of Wild Flora and Fauna (CITES). This is a legal treaty - it restricts or prevents trade in certain species. The list of species can be found here.

Biodiversity Hotspots
Some areas have greater biodiversity than others. Tropical rain forests, mangroves, and coral reefs are examples with high biodiversity.

This leads to the concept of Hotspots. One of the best lists is Conservation International's Biodiversity Hotspots. They have identified 34 area which are both highly diverse and face serious threats. They have also identified 5 other areas with high biodiversity, but with fewer threats.


 * Map of the biodiversity hotspots.

Reserve areas
Key to saving biodiversity is bioreserves

In addition to national parks, etc. there are a number of international recognized reserves:
 * World Heritage Sites - includes both culturally and naturally important sites
 * Biosphere Reserves (PDF) (under UNESCO)
 * Ramsar - Wetlands of International Importance (PDF)

Also related is the WWF's World Ecoregions: Terrestrial Marine Freshwater