Darwin's theory: those that adapt survive

Tuesday, 28 March 2017
The Galapagos are connected to Darwin because he began to develop his theory of Natural Selection after visiting the islands. On the ship, during our vacation there, we were treated to lectures on wildlife and other topics relevant to the Galapagos. Martin, one of the trained naturalists talked about evolution one afternoon.

Sally Lightfoot Crab hunts on the rocks.

He explained Darwinian Theory. The basic concept is that animals produce more offspring than can survive due to natural circumstances or happenings in nature. The stronger, most adaptable live. "Strongest" means that the animal survives, perhaps gets lucky, and he is the “strongest.” This was not what I thought the "Natural Selection" theory was based on. I thought that literally the "strongest" animal is the one to live. Not necessarily so.

Nazca Boobie chick waits to be fed.

Surprise - but Darwin was not a scientist. (Notes based on information from a Silversea publication:) He was born in Shrewsbury, Shropshire, showing an early fascination with the natural world. As a medical student at Edinburgh, he found that he just couldn't handle the trauma of surgery traumatic and decided to get his Bachelor's degree at Cambridge with the goal of serving the Church of England.

In 1831, Darwin joined the voyage of The Beagle as an unpaid companion and Geologist. This experience and more than 20 years of study led to his theory of evolution. He went to the Galapagos, visited 4 islands, and stayed on shore for 19 days.

Sea Lions lounge on the beach after going out to sea to feed.

Ultimately, Darwin's theory acknowledged: “The one most adaptable to change survives.” To expand with an example, it is interesting to note that the Galapagos Tortoises changed the shape of their shells over time to adapt to the landscape of the different islands. Read more about that here. 

Evolution is not directional. When do creatures change and adapt? They evolve when they struggle and suffer then, adaptation occurs. Changes in populations = evolution. Darwin's theory wasn't so much about man evolving from apes but instead he focused on slight CHANGES to the animal. Another example is how, over time, finches beaks changed to accommodate the food supply in the Galapagos islands. Their beaks have evolved so they can eat off the ground, in the trees, from cactus, seeds, etc.

Night gull sits on its nest during the day, preparing to hunt at night.

If an animal doesn’t adapt it is because it doesn’t have a need to change. Species are limited in the Galapagos because food is scarce. The islands are isolated, fragile ecosystems.

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