MAY 22, 2021 7:00 AM PDT

This Lizard Blows Bubbles to Breathe Underwater

WRITTEN BY: Anne Medina

Several species of anolis lizards blow bubbles from their noses to breathe underwater, according to research published in the scientific journal Current Biology this month. While aquatic insects have been documented ‘rebreathing’ air, this ability in the anole a surprising first for reptiles.

Researchers learned that when anole lizards dive underwater—whether to forage for food or escape tropical predators—their rough, water-repellant skin retains a very thin layer of air against the surface of the anole’s body. This silvery wetsuit is called a plastron.

As the submerged anole breathes out through its nose, the plastron expands to form a bubble on the lizard’s head. With the anole’s next inhale, its last breath becomes its next breath—a biological version of the rebreathers than human divers use to conserve and recycle their oxygen supply underwater.  

The researchers suggest that the anole’s air bubbles function as a ‘physical gill,’ allowing exhaled carbon dioxide to exit and fresh oxygen to enter from the surrounding water. The rebreathing technique may also allow a diving anole to access the oxygen stored in the plastron itself, study authors say.

Semi-aquatic anoles—which have been observed in the wild diving for up to 16 minutes without resurfacing—were much more likely to exhibit rebreathing behavior in the Current Biology study, which examined 20 of the over 400 anole species. Phylogetic analysis revealed that the six water specialists that performed best in the trials come from distant branches of the anolis genus, allowing researchers to conclude the rebreathing behavior evolved in several distinct lines.

And while some of the anole species studied didn’t exhibit rebreathing, the silvery plastron formed around every individual tested for the study—in contrast to lizards from other genera examined as controls. Since even anole species that aren’t found near water in the wild form plastrons, it’s unlikely it evolved as a diving adaptation or to facilitate rebreathing, the authors said. Instead, the anoles’ hydrophobic skin was ‘exaptive’—one of evolution’s happy accidents that proved useful in a different context than it was originally selected for. 

 

 

About the Author
  • Anne is a science writer based in the Southeastern United States, one of the unsung biodiversity hotspots of the world. She channels her passion for animals and ecology into her work as a science communicator, making the latest discoveries accessible and engaging for the public.
You May Also Like
OCT 05, 2021
Immunology
Monkey Gene Snares Viruses, Inspires Future Antivirals
OCT 05, 2021
Monkey Gene Snares Viruses, Inspires Future Antivirals
Many of the deadly viruses that affect humans—including Ebola and HIV—have animal origins. These infectious ...
OCT 13, 2021
Plants & Animals
A New Approach to Detecting Fraudulent Food
OCT 13, 2021
A New Approach to Detecting Fraudulent Food
Food fraud is the act of deceiving someone about the food they are receiving, such as its quality or where it came from, ...
OCT 27, 2021
Earth & The Environment
To Combat Deforestation, Research Reveals that Policy Timing is Key
OCT 27, 2021
To Combat Deforestation, Research Reveals that Policy Timing is Key
A duo of Stanford researchers have recently released a study in Global Sustainability that reveals the timing of policy ...
OCT 31, 2021
Genetics & Genomics
Unraveling the History of the Tarim Basin Mummies
OCT 31, 2021
Unraveling the History of the Tarim Basin Mummies
The Silk Road has long been known as a trade route that connected different cultures, and one area now known as the Xinj ...
NOV 09, 2021
Plants & Animals
It Seems a Single Molecule Can Govern Ant Behavior
NOV 09, 2021
It Seems a Single Molecule Can Govern Ant Behavior
Some people change careers, and it seems that the Harpegnathos saltator ant can do the same; worker ants can switch to q ...
NOV 19, 2021
Space & Astronomy
Space Taco: Nasa grows Hatch Green Chiles in space
NOV 19, 2021
Space Taco: Nasa grows Hatch Green Chiles in space
Now, incredibly, the famous pepper has been grown aboard the International Space Station!!!
Loading Comments...