Extinction vortex

Extinction vortices are types of extinction causing the population dynamics to "spiral" in a feedback loop, i.e., for small populations to become increasingly vulnerable as they reduce in size. M. E. Gilpin and M. E. Soulé distinguished between four classes of extinction vortices. The first two (R and D) deal with environmental factors that have an effect on the ecosystem or community level, such as disturbance, pollution, habitat loss etc. The second two (F and A) deal with genetic factors such as inbreeding depression and outbreeding depression, genetic drift etc. This concept helps conservation biologists, geneticists and ecologists to understand extinction events.