Evolution

Hi,

So today, I am going to talk about evolution. We have mentioned this before in our Galapagos Ecosystem series but we’ve never gone over exactly what it is.

So before Charles Darwin thought of his theory of evolution, the majority of people in Europe thought that all species were unrelated and that humans were not related to animals. This was mostly based on Christianity. Darwin studied hundreds of different species and on the Galápagos Islands, he first started to form his theory of evolution.

Darwin's theory of evolution by natural selection, as it was later called, is best explained by the example of the giraffe.

Let's assume that giraffes have short necks (as they did many centuries ago). Now a mother has two children. By chance, one has a slightly longer neck. This is a coincidence. As the giraffes feed on the lower leaves of the trees, these slower disappear. There aren't enough leaves for the giraffes. Thus the giraffe with the shorter neck soon starves to death and only the giraffes with longer necks survive. They then have children who also have slightly longer necks. This continues which means that over many generations, the giraffes develop longer necks.

Examples of evolution can be found everywhere. Probably the best known is the extremely fast evolution of the Galapagos Islands. A diverse number of species developed in just a few thousand years. Apart from that, the evolution of diverse animals in the whole world is very fast. If you imagined the whole history of the earth as a day, life only evolved enough to come onto land from 9pm to 10pm. So all land plants and animals only evolved in the last 2 to 3 hours, while humans only turned up at around 11:58 pm!

Thank you for reading!

Your Green World Blog Team💚

Image:

Charles Darwin: This image, owned by Corin Royal Drummond (on flickr.com), is licensed under CC BY-SA 2.0.

Sources:
https://www.britannica.com/science/evolution-scientific-theory
https://en.wikipedia.org/wiki/Evolution
https://www.nationalgeographic.org/topics/resource-library-evolution/

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