Environmental Science

Chapter 10Biodiversity

Notes #1

BiodiversityWhat happened to the

dinosaurs?A meteor created dust that blocked

the sun?A climate change?A dino with limited predators

destroyed the eggs?Other suggestions?

Biodiversity

Biodiversity at Risk Biodiversity

Number and variety of species on Earth Most of Earth’s species are concentrated in

certain biomes 1.6 million known species

Why are many unknown? Mostly Insects, Why?

Including unknown – probably 10 to 50 million

Biodiversity Extinction – disappearance of a species Mass Extinction

Many species at one time/over a short period become extinct

In the past, all probably caused by climate change

Currently happening faster than ever How are humans causing extinction?

Habitat Destruction Hunting (poaching) Exotic Species

Future of Biodiversity Biodiversity Hot Spots

Areas with many species, in danger of becoming extinct or endangered

Tropical, close to equator, coastal To Save – Large National Parks? Habitat conservation

Plans to protect one or more species in a large area of land

Biodiversity Between 1900 and 2100 it is expected that about

25% of species will have become extinct.

Why does it matter? We lose potential medicines, loss of genetic

diversity, food sources, can ruin whole ecosystem, ethical and aesthetic reasons, etc…

Loss of Keystone species Species that are important to the proper

functioning of an ecosystem Example: sea otter

They kept the sea urchin population in check