Answer
Habitat Loss, Introduced Species, Overharvesting, Global Change
Work Step by Step
1) Habitat Loss: The single greatest threat to biodiversity. Habitat fragmentation leads to species loss because the smaller populations in habitat fragments have a higher probability of local extinction.
2) Introduced Species: Some introduced species disrupt their new community, often by preying on native organisms or outcompeting native organisms for resources.
3) Overharvesting: Species with restricted habitats are particularly vulnerable to overharvesting. Also susceptible to overharvesting are large organisms with low reproductive rates. By overharvesting we are decreasing the population faster than it increases naturally.
4) Global change includes alterations in climate, atmospheric chemistry, and broad ecological systems that reduce the ca- pacity of Earth to sustain life.