Evolution, Intervention and Darwin

Having spent  an amazing 8 days in the Galápagos Islands, it was inevitable that questions started to arise regarding evolution.  The highlight of the holiday for me though was all the amazing snorkelling we did, with sea lions, with turtles, with iguanas, penguins, sting rays and most thrilling of all through lava tunnels with white tipped sharks.  But it was really only when we went to see the giant tortoises both at a breeding centre and in a protected nature reserve that I really started to properly address the islands' importance in the theory of evolution.

Marine iguanas, fur sea lions, frigate birds and blue footed boobies are all over the place.  And they are mostly disarmingly unafraid of man.  On one visit to the beach we left all our stuff on a bench only to find that as soon as our back was turned, a sea lion had nestled herself comfortably into all our towels and clothes!  The blue footed boobies did not fly off even if you walked right up to them, and the iguanas just lay there basking in the sun - not necessarily the most beautiful of sights in their various stages of skin shedding, but very content and oblivious to passers by.  On the beach, patrol personnel traced circles around the iguanas indicating barriers that were not to be crossed, but I never saw one get angry even when you accidentally brushed close by.  The one exception to fearlessness was the "beach master", the dominant sea lion on each beach that fiercely protected all its females, often up to 60 or more, by swimming up and down its area constantly barking.  I came into a bit of a close encounter with one of those but luckily lived to see another day!

It was harder to find the 10 remaining species of Darwin finches that popularly started the whole evolution vs creationism debate and to my eyes they were not so impressive.  But then I'm not really into birds.  The one bird that did stand out was a flycatcher with incredibly vivid orange colouring. The finches we did see looked like, well, finches!  What was made evident by our excellent guide is that there are so many species in the Galapagos that have been isolated in the islands for so long that nothing similar exists elsewhere.  The flora and fauna included.  Nowhere is this more evident than in the tortoise population.  The three main types that we saw on the last island, Santa Cruz, were clearly distinct.  They had been kept separate from each other over the years as the result of volcanic activity. The saddleback is probably the strangest with its shell's extra room allowance enabling the neck to stretch up and reach the succulent parts of the cactus on which it feeds.  This one was about 80 years old.

Darwin's original 13 subspecies of finches are believed to have originally come from one common ancestral type from South America.  With the tortoises it is not so clear how many different species actually landed on the islands; it is commonly believed that pirates threw excess tortoises, a food supply, into the sea and they floated there.  With no natural predators nor other large mammals competing for their food supply they really thrived.  That is until man brought cows and goats and rats and donkeys and blackberries and elephant grass and a whole host of other invasive species.  But the tortoises are thriving again today with the help of Unesco and the Charles Darwin research centre.  

For a moment it did all beg the question whether man should be interfering at all with evolution.  It is so evident that the authorities in the Galapagos are working hard to get everything back to how it all was before man interfered.  For instance, all dogs have to be neutered in the hope that over the years they can be eradicated.  Checks were made every time you moved from one island to another to make sure no animal or vegetables are being transported.  Consistent with evolutionary thinking, there is no culling, and abandoned baby seals or blue footed boobies are left to die. But a damaged or ill tortoise does have to be saved - this is a legal requirement.  Here nature is not allowed to simply "be" whilst numbers are being built back up.  It is easy to argue for this type of interventionism when you see all the magnificent huge tortoises wondering around lush land on a visit to the nature reserve, and you begin to imagine how it must have looked to the 16th century explorers who first landed here.  It is hoped that in about 15 years time the breeding programme can be halted.

I'm not sure whether the Galapagos is really meant to be the show piece for the theory of evolution beyond the specialisation of a species, but it is an incredible place and the people are wonderful.  They know they are lucky to live in such a protected place - immigration is no longer allowed except through marriage.  I had a wonderful time - go there if you can!