As large animals disappear, the loss of their poop hurts the planet

It only takes a glance at a history book and a look out the window to know that our planet has lost many of its biggest creatures: The world that was once home to mammoths and towering dinosaurs can now barely maintain stable populations of rhinos and whales. But according to a new study, we've got more to mourn than just the animals themselves. We've lost their feces, too — and that's a bigger problem than you might think.