Diets rich in beef and other red meat can be bad for a person’s health. And the practice is equally bad for Earth’s biodiversity, according to a team of scientists who have fingered human carnivory—and its impact on land use—as the single biggest threat to much of the world’s flora and fauna. Already a major cause of extinction, our meat habit will take a growing toll as people clear more land for livestock and crops to feed these animals, a study in the current issue of Science of the Total Environment predicts.
Diets rich in beef and other red meat can be bad for a person’s health. And the practice is equally bad for Earth’s biodiversity, according to a team of scientists who have fingered human carnivory—and its impact on land use—as the single biggest threat to much of the world’s flora and fauna. Already a major cause of extinction, our meat habit will take a growing toll as people clear more land for livestock and crops to feed these animals, a study in the current issue of Science of the Total Environment predicts.
“It’s a colossally important paper,” says Gidon Eshel, a geophysicist at Bard College in Annandale-On-Hudson, New York, who studies how human diets affect the environment, and who was not part of the study. Researchers have struggled to determine the full impacts of meat consumption on biodiversity, Eshel says. “Now we can say, only slightly fancifully: You eat a steak, you kill a lemur in Madagascar. You eat a chicken, you kill an Amazonian parrot.” That’s because species-rich habitats are being converted to pasture and feed crops as the human appetite for meat swells.
But others disagree that livestock production is the leading cause of habitat loss. “They’ve created [a] stickman to be knocked down,” says Clayton Marlow, a grassland ecologist at Montana State University, Bozeman, “without accomplishing anything for either the ecosystem or the poor.”
Previous studies have explored links between modern livestock production and climate change, water pollution, and the loss of some herbivores and top predators such as wolves and lions. “But how is it impacting other species?” asks Brian Machovina, an ecologist at Florida International University in Miami, and the paper’s lead author.
To find out, he and his colleagues looked at studies that identified the world’s biodiversity hotspots—those areas that contain the highest percentage of endemic plant and animal species. Most are located in tropical nations. Then, the researchers picked out countries that are most likely to expand their industrial livestock operations, and determined where and how much land will be lost to grazing and growing crops to feed livestock. Using data from the Food and Agriculture Organization and other studies about the production of cattle, pigs, and chickens in these countries from 1985 to 2013 and the amount of land the livestock required, they extrapolated the likely future expansion of agricultural lands. Finally, they created maps of overlap.
Continue reading at Science/AAAS.
Man eating steak image via Shutterstock.
