Which Factor Presents the Greatest Threat to Biodiversity

Question

Which factor presents the greatest threat to biodiversity?
A) habitat loss or degradation
B) introduction of nonnative species
C) overharvesting
D) pollution

Accepted Answer

Habitat loss or degradation is the primary reason for species extinction, which is the ultimate result of biodiversity loss.  It affects both terrestrial and aquatic habitats, leading to the loss of habitat specialists and the fragmentation of ecosystems, which ultimately leads to the loss of biodiversity. Non-native species, pollution, and overharvesting are also significant threats, but they are usually secondary to loss of habitat.