As my readers know I am a nature lover and have a particular affinity toward animals, but you may not be aware that I have been fairly ambivalent about reptiles. That is, until I met the iguanas and lizards of the Galapagos. Though small in stature, these creatures are endlessly entertaining, whether rotating in unison as in the above photo to get the best of the sun’s rays or fiercely defending what they believe is their territory, even if that territory is the hotel pool (more on this in a later post).
I believe Galapagos’ most well-known reptile is the marine iguana. What makes this reptile unique in all the world is that it is the only iguana that swims. When Charles Darwin first came upon the marine iguana he was quite taken aback and wrote in his journal that they were “imps of darkness” and “disgusting, clumsy lizards.” His initial reactions were no doubt revised as the habits of these iguana became one of the cornerstones of his theory of evolution: that these animals, through adaptions to their environment became a strong, thriving species. How?
These marine iguanas over time developed the ability to not only swim but dive as deep as 80 feet to the ocean floor to retrieve succulent algae and seaweed.. Their legs and claws are much stronger than those of other large lizards, helping them to cling to wave-bashed rocks. Their flattened tails help them dive and their noses are also much shorter than land-lizards, helping them get their mouths closer to the rocks to scrape off algae with their short, razor-sharp teeth.
I love their faces most of all – seemingly from a time long, long ago. They appear to be quite stoic, never-changing their expression, although their lives are anything but easy. Some do appear to be a bit smug but I know I am just projecting. Still, they are fascinating:
To be fair, the land iguanas of the Galapagos Island also have great faces:
Back to the marine iguanas. Avoiding the crashing waves and bird predators (more on this later) and diving deep to secure sustenance would be difficult for any animal, but the iguanas have a physical factor that magnifies the issue: they are cold-blooded. That means that they have no internal regulation of body heat and must rely on the sun to warm themselves. While it may seem that they are laid back, in reality they must absorb heat from the sun to stay active – the colder they get the more sluggish their bodies become. What makes the marine iguana’s life even more precarious is the fact that the waters surrounding the Galapagos are usually quite cold. The Galapagos marine iguanas do not breathe when they are underwater and can hold their breath for 30 minutes. However, the cold ocean water will quickly lower their body temperature, so they must stay aware of their bodies’ temperature and leave the water before their cooled bodies become too sluggish to swim or fight off the waves as they emerge onto the rocks. That’s why a good part of everyday is spent finding the perfect spot to “cop some rays:”
Those white splotches on its head are actually salt deposits extracted from the ocean water that the iguana expelled through its nostrils.
Despite their temperature regulating difficulties the marine iguanas glide through water as if they didn’t have a care in the world – even when they bump into a very large pelican:
The brackish water of this pond hasn’t been photoshopped – that vivid orange-yellow is all natural.
There are other dangers that these iguanas, as well as their cousin lizards. face. More on that in Part 2 next week!