The latest research by Lindsey Swierk, a scientist at Binghamton University, has found that a small, semi-aquatic species of lizard, now claims the title of ‘world’s smallest scuba diver.’

Water anoles are a small species of lizard found in Central America, Costa Rica, and Panama. Often found hiding in clusters of rocks near waterfalls, these lizards are always at the top of the menu for birds, larger lizards, and snakes. Lindsey Swierk described them as the “chicken nuggets of the forest” as they are always in high demand from their predators.

Water anoles have many predators to hide from, but they are not very agile, so they use one of the oldest tricks in the book to survive: camouflage. When camouflaging amidst rocks and bark doesn’t quite do the trick, these tiny green and brown lizards dive underwater for cover and breath through a bubble over their heads – it’s their best chance of survival.

After discovering this characteristic of water anoles, many researchers and scientists at Binghamton University wondered if the bubble over the water anole’s nostril functionally extended the amount of time these lizards could hide underwater, or if it was an involuntary action that lizards do.

To investigate whether the bubble played a functional role in breathing or if it is merely a derivation of something else, Swierk and her team applied an emollient to the skin of a group of 13 lizards. The emollient was expected to stop bubbles from forming on the skin. Swierk’s team recorded the time the lizards could stay completely submerged in the water and compared them to the lizards in a control group. She found that the water anoles in the control group could stay underwater 32% longer than the lizards who couldn’t form the bubbles properly.

“This is really significant because this is the first experiment that truly shows adaptive significance of bubbles. Rebreathing bubbles allow lizards to stay underwater longer. Before we suspected it – we saw a pattern – but we didn’t actually test if it served a functional role,” said Swierk.

This experiment showed that rebreathing bubbles can help lizards stay underwater for longer, aiding in hiding from predators.

In the future, Swierk wants to figure out whether anoles could use the bubble as a physical gill. A physical gill in insects uses bubbles to breathe underwater. Insects have less need for oxygen, and the amount of oxygen that diffuses from the water into the air of the bubble is enough for sustaining themselves. Water anoles are likely too big to be completely supported by the oxygen that can diffuse into a bubble although there is a possibility that these lizards could use the bubble as a physical gill.