Human impact on the environment

"When we began and living more closely alongside them, we shared diseases with our new companions. And keeping animals with less than in the wild in crowded, stressful conditions also made them more susceptible to disease. Today, intensive has created highly pathogenic forms of that have infected herds of cattle and their farmers in the US. Then there’s . By and disturbing other habitats, we’ve caused animals stress and forced them to live more closely together. That may have contributed to the spread of from s to apes, monkeys and small forest antelopes known as s. contributes too, by forcing animals and plants to move to cooler regions, and mixing them up with other species. An encounter with a disease that your body hasn’t evolved immunity to is always dangerous."

"Considerable interest in , , and s arose amongst European colonialists who witnessed some of the consequences of Western-style economic development in tropical lands (Grove, 1997). However, the extent of human influence on the environment was not explored in detail and on the basis of sound data until George Perkins Marsh ... published (1864), in which he dealt with human influence on the woods, the waters, and the sands."

"and other activities were responsible for pushing populations of animals to extinction long before the , which began about ten thousand years ago. Today, however, our collective assault on animals, plants, and s has reached such a horrendous level that any alarm we might sound will be too faint to match the tragedy that is unfolding. ... In the past century or so, both the and of Homo sapiens have increased spectacularly, and this is this is the root cause of the rapid acceleration in human-caused species extinctions, precipitating what is now called the ."