Environment Animals Wildlife Bats Why do bats spread so many diseases? Survival of the fittest doesn't always mean smartest, fastest, or strongest. Breakthroughs, discoveries, and DIY tips sent every weekday. There are way more bats than you might think. Second only to rodents, bats make up around a fifth of all mammals, with over 1,500 species of winged nightflyers .

If you're ever feeling down, do yourself a favor and watch some footage from the 2015 Darpa Robotics Challenge. This competition of bipedal beasts put robots up against a number of challenges, from turning valves to driving a car. But they struggled to open doors, much less stand for a decent amount of time. Our face-planting future robotic overlords could stand some improvements. Oh, how the world laughed. And oh, how the world gasped when Boston Dynamics dropped a video of its newest bot, Handle, this week.