The loss of species around the world due to habitat loss, climate change, and other human activities—what many scientists consider a mass-extinction event on par with the dinosaur-killing asteroid—is a tragedy in its own right.
But new research is revealing the hidden ways that thriving populations of many plants and animals—including frogs, vultures, and wolves—underpin humanity's well-being. The decline of many of these species is already taking a toll on human health, leading to thousands of additional illnesses.