Did you know? Sinkholes are created when water flows through certain kinds of rock, dissolving the rock and carrying it away. This creates an underground cavern. When the ceiling gives way, it creates a sinkhole. source

Want to know more? Learn about how scientists study caves to understand their secrets at Science News for Students.

Researchers Katherine and Tim Krynak weren’t looking for shape-shifters. In fact, their discovery was a complete accident. They spotted a tiny, spike-covered frog they hadn’t seen before and took it to the lab to photograph. But when they placed the critter on a smooth surface, the spikes disappeared. When they returned it to a mossy enclosure (thinking they had picked up the wrong frog), the spikes came back. “We simply couldn’t believe our eyes, our frog changed skin texture!” says Katherine Krynak.

The change in skin texture allows the frog to blend in better with its environment. Many animals use some form of camouflage to hide from predators, and some, such as squid and chameleons, even change colors. But this is the first time scientists have found a frog that could change its skin texture to enhance that camouflage. The species is new to science, but the scientists say it has a close relative that shares the shape-shifting ability. However, no one had noticed the changes in skin texture before the discovery of the new frog.

Did you know? Some octopods (a term that means “eight legs”) change not only color, but also their body posture to make themselves look like venomous animals, including lionfish and sea snakes. source

Want to know more? Check out the Exploratorium’s page on camouflage in frogs.