'World's smallest scuba diver' lizard uses bubble to breathe underwater

Life as a lizard can be tricky - trying to avoid getting eaten by birds and other creatures.

Now, new research has found that a small species of lizard - called a water anole - can claim the title of world's smallest scuba diver.

These lizards are not very speedy, so when camouflaging against a rock doesn't work, diving for cover and breathing a bubble over their heads is their best option for escape!

The studies from Binghamton University, in New York, show that the lizard can stay underwater for up to 20 minutes, as it takes in oxygen from the bubble.

These lizards are very little!

What are water anole lizards?

Water anoles are found in Central America, parts of South America and on some Caribbean islands.

They live around rocks and vegetation on small streams and waterfalls.

Their bodies are smaller than the length of a pencil - not including their tails.

Lindsey Swerk from Binghamton University, described them as the "chicken nuggets of the forest".

This is because different predators eat them, including birds, snakes, and larger lizards.

How do water anoles use their bubbles to breathe underwater?

To find this out, the researchers applied a substance called an emollient to their skin to prevent the bubbles from forming.

This was done to investigate whether they had a functional role in breathing.

Lindsey recorded the number of bubbles that the lizards could produce and how long they could stay underwater, and compared them to lizards in a control group that were allowed to breathe normally.

She found that the lizards in the control group could stay underwater 32% longer than those who couldn't properly form the bubbles.

This showed that the bubble helps lizards stay underwater for longer, providing them a place to hide from predators.

How does diving affect the water anoles?

Reptiles are ectotherms, which means they rely on their outside environment to maintain their body temperature.

Diving can drop their body temperature by 6°C and affect how their bodies work.

Like little scuba divers, anoles maintain a “dry suit” of air underwater, which may help them retain some heat.

On average, the researchers discovered that male anoles stayed underwater for 20 seconds less than females. The researchers say it could be the difference between "life and death", as a hungry bird may fly off to find food elsewhere in that time.

They believe this could be as males need to regain their energy quicker so they can look for mates or defend territory.

The team thinks humans can learn a lot from these little lizards and that their bubbles could open the doors to "bio-inspired materials" in the future.