We tend to think of clouds as nice and fluffy, but scientists say that the average cumulus cloud weighs over 1 million pounds.

Parrotfish create a mucus cocoon, nicknamed their "sleeping bag," for protection from parasites.

In the Waitomo Caves of New Zealand, you can explore a spectacular roof filled with luminescent glow-worms that are native to the area.

This bird is called a whooping crane and the color of its eye changes from blue to aqua to gold as it ages.

Instead of blood, starfish have filtered seawater pumping through their bodies.

In 1969, scientist Ágúst Bjarnason was monitoring the progress of plants on Surtsey, a volcanic island, when he discovered a tomato plant in the lava. The mysterious plant had grown from human feces, which is interesting because only a handful of people were allowed on the island (officials wanted to preserve the site, now a UNESCO World Heritage Site, as a living laboratory).

The earth isn't perfectly round, it's oblate. This is due to an imbalance at the equator, where gravity pushes extra masses of land and water into a bulging sphere.

Hummingbirds are the birds with the special ability to fly backwards.

Tens of millions of crabs live on the Australian territory of Christmas Island. They migrate from the forest to the ocean for breeding season, forming an incredible sight.

What do goats, octopuses, sheep, and toads have in common? Rectangular shaped pupils.

The Japanese government officially recognized the enchanting sounds of wind blowing through the stalks at the Sagano Bamboo Forest in Arashiyama as ones that must be preserved.

Although blue whales have hearts that are about the size of a small car, their eyes measure about 6 inches across.

Scientists and locals have been trying to figure it out for several years, but no one knows where the water from Devil’s Kettle Falls, Minnesota, ends up. Many people believe that the pothole empties out somewhere near Lake Superior.

Emperor penguins often go tobogganing on their bellies to get around as their environment can be difficult to walk on.

At over 5 miles long, the Son Doong Cave in Vietnam is the largest cave in the world, but it wasn't discovered until 1991. It's large enough to house a 40-story skyscraper.

Although most seals slither and slide across ice, ribbon seals run.

The Marine Iguana, exclusive to the Galapagos Islands, can its breath for up to 15 minutes.

Vatnajökull, or the Vatna Glacier in Iceland, is one of the largest glaciers In the world. To surpass the amount of meltwater it dumps into the sea each year, it would take Iceland’s biggest river nearly 200 years!

You can hop on the “The Swing at the Edge of the World" at La Casa del Arbol, a small treehouse in Ecuador.

Lake Retba or Lac Rose (Pink Lake) in Senegal boasts an unusual pink color due to Dunaliella salina algae.