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TERRY DOES SCIENCE!
CHARLES DARWIN - EVOLUTION
2009 is the 200th anniversary of the birth of Charles Darwin, one of the finest naturalists that have ever lived.
Darwin was born in 1809 to very wealthy parents. His father, Robert was a doctor with a large country practice and his mother Susannah was a member of the well to do Wedgwood dynasty.
Charles and his brother developed an early interest in Science and convinced their rich father to build them a state of the art chemistry laboratory. They knew that their father was a soft touch and referred to him as the cow to be milked.
Shortly afterwards, Charles took an interest in hunting and spent many hours out shooting birds. His father at one stage lost his temper with him declaring that he cared for nothing but shooting, dogs and rat catching and that he would be a disgrace to himself and all his family.
It was then decided that Charles should pursue a serious career and his father enrolled him at Edinburgh Medical School.
During his first year in Edinburgh young Darwin had a great time drinking and partying. Money was no object to the Darwins, and Charles was having the time of his life. However, he showed little interest in his studies just scrapped through his exams.
Shortly afterwards he watched a particularly gruesome operation on a young child without anaesthetic. He was physically sick and ran out of the operating theatre, never to return.
His father then decided that he should study for the Church and he was enrolled at Cambridge University. While he was there, he became interested in natural history, especially beetles. He became close friends with John Henslow, the Botany professor. Henslow became an inspirational figure in Darwin's life and he at last settled down, studied hard and graduated from Cambridge, but he had little interest in joining the clergy. By now he was a dedicated naturalist.
Shortly after finishing at Cambridge, he was offered the chance of travelling abroad as a naturalist on the upcoming expedition aboard the Beagle under Capt. Robert Fitzroy.
He accepted and both men hit it off immediately.
Darwin spent 5 years on the Beagle with Fitzroy, much of which he was seasick. In fact, after he returned in 1836, he never left England again.
When Darwin left England he was a confirmed Creationist, but by the time he returned, he had changed his mind. He had brought with him a copy of the recently published Principles of Geology. From this he learned that the physical world was constantly changing and the age of the Earth was measured in hundreds of millions of years.
Creationists believed that the Earth was much younger. The Irish Archbishop James Usher, stated that the Earth was created on the 23rd October 4004 BC. They believed that once Adam had named all the plants and animals, these original forms bred true and never changed. For a long time, this led scientists to disregard the significance of fossils, which were often dismissed as an interesting coincidence, or that God had playfully decorated his rocks with ornamental replicas of living things.
Before he left England, Henslow had agreed to accept and mind all those specimens that Darwin would send home, and Darwin, sent home shiploads.
Towards the end of the voyage, the Beagle landed on the Galapagos Islands off the west coast of Ecuador. The Galapagos, the name comes from Spanish meaning - islands of the tortoises, are a group of relatively young volcanic islands, about 600 miles from the mainland.
Darwin spent just 5 weeks there, but what he saw there changed his views completely. When he landed, he was met by the Governor of the islands, an Englishman called Lawson. Darwin was amazed that Lawson could tell him from which island any individual tortoise came. By carefully looking at the shape of the shell of the tortoise, Lawson showed him how they differed from island to island. Some had round shells. Others had shells with curved arches at the front. On each island the vegetation differed and the different shape of shell allowed the different tortoises to take advantage of this.
Later, Darwin saw the same subtle changes in the finches on the islands. At the time, he didn't realise they were all finches. In fact he called one a blackbird and one a wren. But he did see that their different shaped beaks allowed them to feed on different food items. Those that fed on seeds had thick strong beaks, while those that fed on small insects had delicate pointed beaks.
Darwin also knew that the islands were physically changing, and he wondered could the animals be changing too.
Before he could come to any conclusions, it was time to travel back to England. It had been a long 5 years away from home.
Darwin had formulated many of his ideas about evolution shortly after he returned in 1836. With the help of experts, like John Gould, he set about studying and cataloguing the huge collections he had sent home. In fact it was Gould who identified the birds as finches, 13 different species in all, which were later renamed Darwin's finches in his honour.
Over many years, Darwin developed his theory of Evolution, or transmutation of species, as it was then called. He published his now famous book on the Origin of Species by Means of Natural Selection in 1859 - more than 20 years after his voyage on the Beagle.
It was a huge success with the first edition selling out on the first day of publication. It was greeted with enthusiasm by the scientific community and it explained his theory in a manner that was easy for everybody to read. When his friend and colleague Thomas Huxley first read it he exclaimed: How stupid of me not to have thought of it before?
On the Origin of Species changed the world forever and the Galapagos were the origin of Darwin's views - The Origin of the Origin of Species.
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