Watch The World’s Only Swimming Lizard In Action

Published April 11, 2016
Updated December 13, 2022

Watch the one-of-a-kind marine iguana swim through the sea and learn how fascinating these bizarre, endangered creatures truly are.

The Galapagos Islands, infamous for the creatures Charles Darwin witnessed as he was shaping his theory of evolution, lives up to its reputation as home to some of nature’s most mysterious inhabitants. As proof of that, look no further than this recent video of a marine iguana foraging near Cabo Marshall.

The marine iguana, Amblyrhynchus cristatus, is unique to the Galapagos Islands and the only sea-going reptile on the planet.

Amblyrhynchus cristatus is an herbivore and swims in cold water in search of the algae beds that provide the majority of its diet. These iguanas are able to dive as deep as 30 feet, and can remain submerged for up to half an hour.

Their flattened tail is ideal for propelling them through the water, while their hands and feet hang limply at their sides. Their short noses make it easy to feed on algae.

As marine iguanas eat, they also swallow seawater which they must sneeze out once they resurface. While underwater, the reptile’s main predators are the sharks who can hear their heartbeats from up to 13 feet away. However, these iguanas are able to voluntarily stop their hearts for up 45 minutes to deter the sharks.

Research has shown that the marine iguana diverged from its land-dwelling counterpart about 8 million years ago, and originally floated to the Galapagos from South America on rafts of vegetation.

These days, the marine iguana can be found almost everywhere on the Galapagos Islands. Barbara Holzman, a professor of geography and environment at San Francisco State University, points out that extinction is unlikely for the marine iguana, unless El Niño events, which raise sea levels and increase the ocean’s temperatures, deplete the iguana’s food source.

But, in adapting to climate change by increasing mating following an El Niño phase, this is one resilient reptile.

After learning about marine iguanas, check out some astounding Charles Darwin facts. Then, learn about Project Isabela, which is seeking to conserve the Galapagos Islands through unconventional means.

Elisabeth Sherman
Elisabeth Sherman is a writer living in Jersey City, New Jersey. She holds a Master's in writing from Columbia University, and her work has appeared in Food & Wine, The Guardian, Yahoo, BBC, HuffPost, VICE, MSN, and Vulture.