Vulture populations in India collapsed. 500,000 people died as a result. In the 1990s, Indian farmers started using a cheap painkiller called diclofenac on their cattle. When vultures ate the carcasses, the drug destroyed their kidneys. Without vultures, cattle carcasses rotted in fields instead of being stripped clean in 45 minutes. Feral dog populations exploded by five million. Rabies cases surged. Pathogens spread through water supplies. University of Chicago economists compared death rates in districts that used to have vultures to districts that never did. Human mortality rose more than 4% after the collapse. Over 100,000 extra deaths a year. Half a million in five years. India banned the drug in 2006. The vultures still haven't recovered. This is what a keystone species is to us. This is why we protect the animals nobody finds cute.