Approximately 26 percent of the world's land area – including one-third of tropical and temperate forests, and a quarter of natural grasslands – have been converted for the use of agriculture and livestock. And scientists estimate that currently, annual conversion of wild lands for agriculture continues to reduce 1.5 percent of the total rain forest on earth.
These staggering figures demonstrate how significant an impact human food consumption and farming practices are having on wildlife habitat. But while some types of farming and grazing practices are less harmful than others, certain types of agricultural clearing methods such as "slash and burn" or "shifting cultivation" are being used in inappropriate climates resulting in highly unsustainable farming efforts and significant losses to biodiversity.
These methods of land clearing burn down forests to create new fields for agriculture. However, in tropical climates, the nutrients from the burns can only sustain healthy crop yields for a limited time before the farmers are forced to burn more forest and start over on a new piece of fertile land.
Although slash and burn agriculture has been found inefficient and destructive for large populations in tropical areas, the process is still frequently practiced.
On the island country of Madagascar, Africa, the continued use of slash and burn clear-cutting is speeding up erosion processes and eating away jungle forests that provide the only known homes for many species of lemurs.
LEARN MORE: Discover responsible land use
Between 1950 and 1985, one half of Madagascar's forests were depleted, and only about 10-20 percent of the county's original forest cover exists today. With 150,000 to 200,000 hectares still cleared on the island annually for farming, the amazing prosimians of Madagascar are in great danger of disappearing.
Reflecting an increase in demand similar to the market for food crops, livestock products and production have tripled since 1970. As a result, clearing forests for animal husbandry is occurring worldwide.
One prominent example is seen in Central America. This area of the world, where ranching has been practiced since colonial times, is host to 23 species and subspecies of primates.
With American markets in search for cheap beef, many Central American ranchers have capitalized on this opportunity by expanding their operations and moving into the humid forests of the Atlantic watershed. The livestock land area of Central America is estimated to have grown from 3.9 million hectares in 1955 to 13.4 million hectares in 1995.
Much of this expansion was at the expense of the area’s tropical forests, the primary habitat for indigenous primates.
READ MORE: Habitat loss is also caused by logging, development, and fires.