The much-maligned marine iguanas of the Galapagos Islands are so famously despised, even Charles Darwin described them as “hideous-looking” and “most disgusting, clumsy lizards.” But what these unusual creatures lack in looks they make up for with their amazing and unique ecological adaptations. Marine iguanas are the only living species of marine reptile, feeding almost exclusively on algae that grows along the rocky shores of the island.
Researchers theorize that land iguanas and marine iguanas evolved from a common ancestor in Central or South America, with the marine iguanas ending up on the islands by accident and having to adapt to a new environment. And adapt they did: their short, blunt snouts and small, razor teeth help them scrape the algae off rocks, and laterally flattened tails let them move crocodile-like through the water. They also adapted special glands that clean their blood of extra salt, which they ingest while feeding.
Marine iguanas are under constant pressure from non-native predators like rats, feral cats, and dogs, who feed on their eggs and young. They are also affected by changing weather patterns, such as increasing storms and El Ninos, that affect their food source. Iguanas are protected throughout the archipelago, and are considered Vulnerable to extinction.