How long do species usually last before they go extinct?
It turns out the answer we find now could be very different than it usually is. Because of habitat destruction, climate change, and a range of other factors, plants and animals are disappearing from the planet faster than all but maybe five other points in history. Some experts say we’re in the sixth mass extinction event. But even in calmer periods of Earth’s history, the answer has varied depending on the type of species you’re looking at. For mammals, the average species exists for 1 million to 2 million years, according to an article in the journal People & the planet.
There are several reasons why estimates of the current extinction rate vary. “The extinction rate is based on how many species are on Earth and how rapidly they’re going extinct,” [Center for Biological Diversity’s Senior Scientist Tierra] Curry said. “And no one actually knows the answer to either one of those questions.”
One thing the experts do agree on is that the modern extinction rate is far too high. “Species are adapting as fast as they can,” [conversation ecologist Stuart] Pimm said. “But eventually the luck runs out and they don’t adapt fast enough. And they go.”