Iguanas are not typically considered marine creatures — except for the marine iguana. This species of iguana has evolved to be a master of the underwater world, relying greatly on what the ocean has to offer. Their bodies possess unique features that make them exceptional aquatic reptiles. This video from BBC Earth looks at how marine iguanas feed underwater. Read below to learn more about the diet and evolution of marine iguanas.
The Galapagos Islands are home to many creatures that have adapted to the lava and heat, including marine iguanas.
©Anastasia Koro/Shutterstock.com
All About the Marine Iguana
The marine iguana, known scientifically as Amblyrhynchus cristatus, is a species of lizard found exclusively in the Galápagos Islands. Another surprising fact: they are the only lizard species in the world that regularly forages for food in the ocean. With a typical lifespan of 10 to 12 years, marine iguanas are around four feet in length, and they weigh anywhere from two to four pounds. Their bodies have undergone multiple adaptations to make them skilled at aquatic life. These include dark skin that helps absorb heat after diving and heavy bones to stay underwater for longer. They also have claws specialized for holding onto slippery surfaces and salt glands that expel salt from the ocean through their noses.
Marine iguanas are strict herbivores, feeding exclusively on marine algae and seaweed. To meet their nutritional requirements, the iguanas feed on red and green algae and seaweed found on underwater volcanic rocks around the islands. They can hold their breath for 30 to 40 minutes while feeding underwater, and in rare cases, even longer. Staying underwater for 30 minutes may seem difficult, but marine iguanas can lower their heart rate from around 40 beats per minute to as low as 10 beats per minute while diving. This allows them to conserve oxygen and maintain a warmer body temperature. After diving, they sunbathe to warm themselves back up. Using their flattened tail like a paddle, they are excellent swimmers.
Marine Iguanas are herbivores that feed mostly on algae.
©Andy Deitsch/Shutterstock.com
More About Their Adaptations
As mentioned above, there are many different traits of marine iguanas that make them excellent marine reptiles. To counteract the chilly effects of the water, the lizards’ dark skin colorations let them absorb heat quickly. Because iguanas are cold-blooded, this is crucial for their survival. Their bones are also incredibly dense, acting almost like anchors. Unlike humans, who naturally float in water, marine iguanas’ dense bones allow them to sink further while diving to access more algae. One final feature is their blunt snout and special teeth. Marine iguanas have tricuspid teeth, or teeth with three points. This enables them to scrape algae cleanly off rocks, a task they would otherwise be unable to perform. These amazing creatures are a marvel of evolution.
The post The Marine Creature That Must Find Food in 30 Minutes or Less appeared first on A-Z Animals.
