The Galápagos Islands have the only habitat in the world where you can find marine iguanas.  How and why did this happen?   Geneticists believe that  over 10.5 million years ago, ancestors of today’s marine iguana came  to the islands from South America on floating rafts of vegetation. In a classic display of the theory of evolution, some of the these iguanas discovered a great food supply in the underwater algae and over time developed the physique best suited to swimming.   Land iguanas and their smaller cousins, the lava lizards also were and are successful in finding sustenance of another kind –  plants, shrubs, fruits and cactus pads. They are not total vegetarians, as they also might nibble on small crabs or a grasshopper or two.

Marine iguanas have also shown a life saving ability to alter not only their eating habits, but also their actual bodies in order to survive. When natural events, such as El Niño (“an irregularly occurring and complex series of climatic changes affecting the equatorial Pacific region and beyond every few years, characterized by the appearance of unusually warm, nutrient-poor water off northern Peru and Ecuador, typically in late December.” ) wreaked havoc on the habitat, killing almost 70% of the islands’ marine iguanas in 1982-83, the remaining marine iguanas turned to the foods eaten by land iguanas, as listed above.  Most surprisingly, they actually CHANGED their bodies to better adapt to the hotter conditions, Whereas most animals get thinner when they go hungry,  marine iguanas also  get shorter!  Once the food supply returns, they regrow. Throughout  their lifetime marine iguanas can switch between growth and shrinkage.  Truly remarkable.

These creatures have not only found ways to fight the environment, they are also immensely successful at retaining their numbers despite the presence of predators, whether they be endemic – hawks, owls and snakes, but also from those brought to the islands by man – rats, dogs, cats and goats.  This is particularly noteworthy since humans have not been successful at removing the creatures they brought to the islands.

This feistiness is found not only in the marine and land iguanas, but even down to the tiny lava lizards. These lizards are tiny but have lion hearts that fiercely defend their territories. We came upon these two male lizards that were so engrossed in their fight that they didn’t stop even when we approached:

There was another lava lizard who decided that the pool area at our hotel belonged to him.  I had fun bobbing my head at him (its one of their intimidation gestures) – guess he never saw a lizard that looked like me:

I am sure this little lady lizard would have been impressed –  Interestingly,  in a switch up of usual nature coloration the females have the more vivid coloration:

Don’t know if you are aware that lava lizards are also part of pop culture – remember this scene from Kevin Costner’s baseball movie, “Bull Durham?” Annie, played by Susan Sarandon, gives newbie pitcher, Nuke Laloosh, played by Tim Robbins some advice on how to straighten out and control his powerful, but wild pitching:

Annie: “I want you to breathe through your eyelids.”

Nuke: “My eyelids???”

Annie: “Like the lava lizards of the Galapagos Islands.”


Back to the real world.  Sometimes, in the face of danger, particularly by predators, the best defense for these mini-dragons is to stand/lie immobile.  We got to witness this up close and personally in an area only accessible by boat. Named Las Tintoreras (“The Chasms”) this collection of islets created by ancient lava formations is a stark landscape that frankly looks like “The Land That TIme Forgot.” There is virtually no vegetation and the lava formations are razor-sharp so one needs to take particular care to stay on the very narrow sandy trail.  In a later post I will show you pictures of this otherworldly place.

The Tintoreras may seem inhospitable, but the islets are actually teeming with all sorts of wildlife, including our beloved marine iguanas.  In fact, there was nowhere else on the Galapagos where I was able to see such a multitude of babies and juveniles.  These babies are an egret’s delicacy, but on the day we visited, a large heron, despite its excellent eyesight, just stared at the thousands of marine iguanas literally within beak’s reach seemingly without  the urge to scoop up a meal. The heron was a scant few feet away so it was fascinating to see he didn’t attack. I’ll share pics of this beautiful and thankfully hungry heron (didn’t really want to see these mini-dragons eaten in front of me) and his other heron relatives in another post.  By mobbing together and then staying perfectly still, the marine iguana youngsters we saw lived to swim another day.

As we left Las Tintoreras, one sole marine iguana stood watch at the edge of the water.  It was a perfect way to end the day:




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