Starts With A Bang

Science discovers how complex life came to the Galapagos Islands (Synopsis)

Satellite photo of the Galapagos islands overlayed with the Spanish names of the visible main islands. The islands themselves are, at most, only a few million years old. Image credit: Jacques Descloitres, MODIS Rapid Response Project at NASA/GSFC.

“I was always amused when overtaking one of these great monsters [a tortoise], as it was quietly pacing along, to see how suddenly, the instant I passed, it would draw in its head and legs, and uttering a deep hiss fall to the ground with a heavy sound, as if struck dead. I frequently got on their backs, and then giving a few raps on the hinder parts of their shells, they would rise up and walk away; – but I found it very difficult to keep my balance.” -Charles Darwin

The Galapagos Islands house some of the world’s most unusual and uniquely adapted plants and animals in the world. This includes giant trees that evolved from the humble dandelion, tortoises the size of boulders, and birds and iguanas that feed beneath the sea. It shouldn’t be a big surprise that plants and animals made it to this remote region of Earth, given wind, ocean currents and flying/swimming animals.

The large plants and animals of the Galapagos Islands, including the large tortoises for which the island is named, require volcanic rock to be transformed into fertile soil. Image credit: David Adam Kess of Wikimedia Commons.

But it is surprising that they were able to thrive on these volcanic islands, given that igneous rock has none of the properties you need for rich, fertile soil. Yet the physics of the islands themselves allow them to create their own rain, which leads to the incredible habitats they now exhibit today. All it takes, after that, is the arrival of plants and animals capable of filling those niches.

The rising air over the tall island mountains on the Galapagos result in rain, which result in the creation of soil and the eventual greening of the island, particularly at the highest elevations. Image credit: Sean Russell / flickr.

Come get the story of how science brought habitability to the Galapagos Islands!