Four Major Threats to Biodiversity

 Many different human activities threatens biodiversity on a local, regional, and global scale. Of this long list, most species loss can be traced to four major threats: habitat destruction, introduced species, overexploitation, and disruption of interaction networks such as food webs.
Habitat Destruction
Human alteration of habitat is the single greatest threat to biodiversity throughout the biosphere. Massive destruction of habitats has been brought about by agriculture, urban development, forestry, mining, and pollution. Habitat destruction may occur over immense regions. Sadly, 98% of the tropical dry forests of Central America nad Mexico have been cleared or cut down. Habitat loss is also a major threat to marine biodiversity. 93% of coral reefs have been damaged by human activities.
Introduced Species
Introduced species are species that humans move from native locations to new geographic regions. Free from predators, parasites, and pathogens, such transplanted species may spread through a new region at exponential rates.
Overexploitation
Overexploitation refers generally to the human harvesting of wild plants or animals at rates exceeding the ability of populations of those species to rebound. Species with restricted habitats are very vulnerable to overexploitation.
Disruption of Interaction Networks
The extinction of a keystone species can lead to the extinction of many other kinds of species.