Borneo is the third largest island in the world and comprises the nations of Malaysia, Brunei, and parts of Indonesia. It's one of the most incredibly diverse places on the planet, home to 15,000 plant species, 3,000 different trees, 221 different land mammal species, and 420 unique birds. And that number is constantly growing, as 361 new species have been discovered just in the last fifteen years. Here's a look at just a few of the amazing animals that live in the vast Borneo rainforest.

For instance, consider the Bornean flat-headed frog, which you can see up top. Scientists have known about this frog for awhile, but it was only in 2008 that they discovered that this is the first known lungless frog. This species, unique among all frogs, breathes through the skin, which allows other organs to slide into where the lungs would otherwise be. This makes the frog look flatter, which in turn creates more surface area for oxygen to be absorbed. The flatness also makes the frog more aerodynamic, which helps it navigate the speedy currents of it stream habitats.

Image by David Bickford.