Marine iguanas are the only lizards on Earth that spend time in the ocean and live only on the Galapagos Islands. Populations across the archipelago have been isolated from each other for so long that each island has its own subspecies. Marine iguanas are also known for their very efficient salt glands, where they “sneeze” out salt. Because they feed underwater, they ingest a large amount of saltwater. In order to prevent dehydration, they must expel salt without expelling water, so they have specialized glands that remove salt from the blood. They also have the incredible ability to shrink (in length and in overall size). In times of reduced food availability – particularly during El Niño climate events – they may shrink by as much as 20%. The now smaller individuals require less food. Once their preferred algae return to high levels, they quickly regain the lost size.
Credits sourcehttp://oceana.org/marine-life/sea-turtles-reptiles/marine-iguana
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