How did you do that? What is the secret of lizards to breathe underwater? A team of evolutionary biologists at the University of Toronto found out. They use a bubble that sticks to their snouts.
Anoles are a diverse group of lizards found in tropical America. They often dive underwater to avoid predators. You can stay underwater for up to 18 minutes.
“We found that semi-aquatic anoles breathe air into a bubble that sticks to their skin,” says Chris Boccia. He is a graduate of the Department of Ecology and Evolutionary Biology of the Faculty of Arts and Sciences (EEB). Boccia is the lead author of this article. The description of the finding can be found in Current Biology.
“The lizards then breathe the air again,” says Boccia. “A maneuver that we called ‘breathe again’ after diving technology.”
The researchers measured the oxygen (O2) content of the air in the bubbles. They found that it decreased over time, which confirmed that re-inhaled air was involved in breathing.
Reinspiration probably arose out of the need to survive. Prolonged immersion increases the likelihood that the lizard will evade predators.
The authors examined six types of semi-aquatic anoles. They found that they all possessed the trait of rebreathing, although most of the species were distantly related. Rebreathing has been extensively studied in aquatic arthropods such as water beetles. Not to be expected in lizards. Especially because of the physiological differences between arthropods and vertebrates.
“It wasn’t a possible natural mechanism for underwater breathing in vertebrates,” says Luke Mahler. He is an assistant professor at the EEB and a thesis supervisor at Boccia. However, our work shows that this is possible. The lizards’ secret to breathing underwater has been revealed. Anoles have repeatedly used this strategy on species that use aquatic habitats. ‘