Scientists believe that 99% of the estimated 50 billion species that have ever lived on Earth have disappeared through extinction. This is a natural process typically, but it can also be cataclysmic and it’s becoming clear we are amid a massive one.
Being ravenous eaters of decaying flesh, vultures have long been shunned by humans. But because of their disgusting habits, vultures provide a much-needed service to the rest of the organisms on Earth, making them the unsung heroes of their ecosystems.
Redheads are supposedly fiery, passionate people, but is there any truth to these stereotypes? Find out what studies have to say about redheads -- and if they'll really go extinct soon -- in this HowStuffWorks podcast.
Is Earth due for a mass extinction? Population ecologists think so. Check out this HowStuffWorks podcast to learn more mass extinctions.