Biodiversity Unit 3 Environmental Science 1

What is diversity? Diverse: differing from one another; composed of distinct or unlike elements or qualities Diversity: the condition of being diverse Biodiversity: Biological diversity in an environment indicated by number of different species of plants and animals

Why is there diversity? Charles Darwin came up with the concept of “Law of Natural Selection” – meaning only the fittest survive If only the fittest survive – why so much diversity? Over time organisms develop a niche in the environment – they serve a purpose and in turn the environment needs that organism to function

Why is there diversity? If only the strong survive, why are there so many organisms? Three reasons: 1. Because of niches 2. Geological separation 3. Environmental factors

Why is there diversity? Niches: Niches are jobs or roles an organism has in a particular ecosystem If two organisms are competing for the same niche the weaker organism will “lose” – this is simply called competition An exotic or invasive species has no competition or predators and can overtake and/or destroy an ecosystem

Why is there diversity? Geologic separation For example, the same species may be separated by migration, plate tectonics, etc and adapt to a new environment and as a result a new species forms Environmental reasons The warmer and wetter the climate the more diversity it can hold because there is less fluctuation in conditions

The Importance of Diversity Biodiversity is important to human survival For example, was seen in the potato famine of the 1840’s – only a few species of potatoes were planted and when a fungus killed off the potatoes 2 million people died of hunger and disease

Importance of Diversity Reasons for preserving biodiversity All life has a right to exist Variety adds enjoyment to life Diversity brings stability to our biosphere Diversity has economic and medical value Modern agriculture is tied to biodiversity

What effects biodiversity? Competition is when two organisms are competing for similar resources – they both fill the same niche When two organisms are in the same niche resources become scarce one or both organisms become effected

What effects biodiversity? Adaptation effects biodiversity by increasing it – an organism that is adapted to a variety of environment is less limited in where it can live – that is one of the reasons why there are so many humans on the planet

How to Preserve Diversity Set aside large areas of land to preserve the wilderness in the form of parks, monuments and wildlife refuges Collect, preserve and maintain a variety of seeds from different areas Use genetic engineering to change genetic information at the molecular level

Endangered Species Extinct: the last remaining member of the species has died, or is presumed beyond reasonable doubt to have died Examples: Thylacine, Dodo, Passenger Pigeon Extinct in the wild: captive individuals survive, but there is no free-living, natural population Examples: South China Tiger, Alagoas Curassow

Endangered Species Critically endangered: faces an extremely high risk of extinction in the immediate future Examples: Arakan Forest Turtle, Javan Rhino, Brazilian Merganser Endangered: faces a very high risk of extinction in the near future Examples: Blue Whale, Snow Leopard, African Wild Dog, Tiger, Albatross, Crowned Solitary Eagle

Endangered Species Vulnerable: faces a high risk of extinction in the medium-term Examples: Cheetah, Gaur, Lion, Wolverine Conservation Dependent: The following animal is not severely threatened, but the animal must depend on Examples: Spotted Hyena, Leopard Shark, Black Caiman

Endangered Species Near Threatened: may be considered threatened in the near future Examples: Blue-billed Duck, Solitary Eagle, Small-clawed Otter, Maned Wolf Least Concern: no immediate threat to the survival of the species Examples: Brown Rat, Nootka Cypress, Wood Pigeon