Scientists have just announced the discovery of a ‘new’ iguana species found in the Galapagos Islands – the pink iguana. It seems unreal that a large pink lizard would go undetected in one of the most heavily-studied areas on earth until now – unless you understand the inherent difficulties in ‘discovering’ a new species. The pink iguana was not unknown before now – to the left is a 2006 photo of it, in a Galapagos Islands brochure.

So if there were photos of it in 2006, why was it not ‘discovered’ until now? The difficulty lies in determining if an animal is in fact a new species, or if it is just a variation on an existing species. In the days prior to DNA testing, it was even more difficult, but even today, before DNA tests can be done, someone needs to wonder if the creature could be a different species than previously thought.

In order to really understand how a giant pink lizard didn’t cause anyone to wonder, we have to know some things about the Galapagos Islands. The islands are all volcanic, the creation of an oceanic ‘hot spot’, basically an underwater volcano, that periodically erupts, forming islands. This means that unlike many other island chains, the Galapagos Islands have never been connected to any other land mass. The plants and animals that colonized the islands, therefore, have developed in isolation since they first arrived. Take, for example, the iguana. It’s not clear how iguanas got to the islands in the first place, but it’s likely that they arrived clinging to floating wood or vegetation, originally swept into the sea from the coast of South America. But when the iguanas washed ashore in the Galapagos, they found that the barren volcanic islands offered little in the way of fresh vegetation, their main diet. Some of the iguanas made their way to areas on the islands that offered enough greenery to survive, and adapted further to sustain themselves during the long dry spells in the islands. These iguanas became the land iguanas of the Galapagos. Their much more famous cousins, the marine iguanas, adapted themselves in a different way – they learned to eat the algae that grows on the rocks on the shorelines of the islands.

Further, each iguana eventually developed slightly differently on each island, as the conditions on each island vary. The most noticeable of the changes are in color. Each island in the Galapagos has its own unique color of iguana. Some of them are mostly black, to blend in with the mostly black lava. Some of them have more green on them, for islands that have more vegetation. Many are slightly reddish, on islands that have redder soil. During mating season, all the iguanas develop much brighter colors, and some develop patches of colors that they do not have during other times of year. We can see where this is going, right? On some islands in the Galapagos, there are iguanas that have brilliant pink and green patches during mating season. A pink iguana, in other words, is not so unusual.

Take a look at the photos below. The first one is of the 'new' pink iguana. The next two are of one of the already known species of land iguana. You can see the problem! (The last photo is cheating a little bit - that iguana is more of a peach color than pink - it was just the quality of the light that made it look so pink.)



Given the large variations in color of the Galapagos iguanas, it was easy to assume that the pink iguana was simply another color variant, rather than another species, and this is what led the pink iguana to be ‘undiscovered’ for so many years.

There are entire books written about speciation and the processes, pre-DNA, used to determine if something is a new species or not. But for now, what we need to realize is that the discovery of a new species, while cause for celebration, does not necessarily mean that there is a new form of life on earth, that has never been seen before. In most cases of land animals, it is more likely to be simply a case of finding that an already-known animal is in fact a different species, rather than a sub-species or variant.

However, that doesn’t mean that there is nothing truly new under the sun. In some cases, such as the recent flurry of discoveries of new species in the oceans around Indonesia, the new species are indeed totally new. The ocean is a vast and largely unexplored country, and as technology is allowing us to study it more and more, it is providing us with a wealth of fascinating new species. Stay tuned to this spot for a more in-depth look at our newly-discovered ocean-dwelling friends.