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Environmental Studies
IDC3O3
Ms. Nguyen and Ms. Topp
*Biodiversity or ‘biological diversity’, refers to the
variety of life on Earth
*It includes all living things, including plants,
animals, micro-organisms, and their unique
characteristics
*‘We’ divide the concept of biodiversity up and
look at it at 3 different levels – can you guess what
they are?
*Three levels of biodiversity:
*1) Ecosystems
*2) Species
*3) Genes (genetic diversity)
*= the variety of habitats, living communities, ad
ecological processes on Earth
*Biodiversity at this level is important because
ecosystems provide natural services for us:
*Ecosystem services such as pollution breakdown
and absorption
*Biological resources, such as food
*Social benefits, such as recreation and tourism
*Ultimately, ecosystem diversity ensures the
health of the entire planet!
*= the variety of species in a given area
*Species diversity is important because species
ensure that ecosystems survive
*Why? Each species depends on the services
provided by other species to ensure survival
*Creates a balanced ecosystem – which ensures
ecosystem services function properly too!
*Everything is interconnected
*= the variety of genetic characteristics in a species
*Genetic diversity ensures that parents pass on the
traits that their offspring need to survive
*E.g. of traits = disease resistance and physical
features
*Overall, genetic diversity in a population
increases the ability to avoid inbreeding and
withstand stress
*There are estimated to be between 5 million and
20 million species on Earth
*We’ve only identified 1.8 million species
*56% of species = insects
*14% = plants
*3% = vertebrates
*It is estimated that Canada has ~ 140,000 different
species
*Unfortunately, we are losing species at an
unprecedented rate – estimated to be up to 1000x
greater than the natural rate of extinction!
*Experts believe we are witnessing
the next major
mass extinction event – the last being the
disappearance of the dinosaurs.
*Major threats to biodiversity loss are:
*Habitat loss and degradation
*Climate change
*Excessive nutrient load and other forms of pollution
*Over-exploitation and unsustainable use
*Invasive alien species
*Video from the International Union for
Conservation of Nature (IUCN)
*http://www.globalissues.org/article/171/loss-ofbiodiversity-and-extinctions
*TED Talks – EO Wilson – On saving the life on earth.
*http://video.ted.com/talks/podcast/EOWilson_2007.mp
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