3.6 human impact Flashcards
1
Q
what do scientists believe the background extinction rate is?
A
1 per 1,000,000
rate of 10-6 yr-1
2
Q
how many periods of mass extinction have there been been?
what one are we in now and what is it due to?
A
there have been 5 periods
we’re in the 6th due to human activity rather than catastrophic changes
3
Q
what are some reasons species are threatened?
A
- natural selection
- non-contiguous populations
- loss of habitat
- overhunting by humans
- competition and introduced species
- pollution (oil disasters and PCBs)
4
Q
define conservation
A
the protection, preservation, management and restoration of natural habitats and their ecological communities, to enhance biodiversity while allowing for suitable human activity
