Reader Brian P. Block looks at why the work of Charles Darwin is so important.

Only those who avoid both the printed and broadcast media could be unaware that this month has marked the 200th anniversary of the birth of Charles Darwin. Why all the fuss, one might ask; so he discovered evolution, it’s only a theory.

Everybody’s views about what constitutes greatness differ, yet one would be hard pushed not to count him alongside William Shakespeare and Isaac Newton as the three greatest Englishmen, and in the nineteenth century he stands with the three other exceptional men who changed the way we see the world: Karl Marx, Sigmund Freud and Albert Einstein.

In some ways he was different from them: he did not come from middle Europe, he was not Jewish and he was never an exile.

Furthermore, whereas the ideas of Marx and Freud have been largely discredited, and those of Einstein are comprehensible only to physicists and mathematicians, Darwin’s easy to grasp contribution has been expanded and refined as the years have passed.

In terms of his achievement of enabling us to understand the world and man’s role in it, he is arguably the greatest Englishman ever.

Darwin was born in Shropshire and at that time understanding how the world and life on it began resolved into a belief in the creation story of Genesis. Darwin was to demonstrate otherwise.

Darwin’s family were middle-of-the-road Church of England, although his mother, who died when Charles was eight, was rather more fervent.

He went up to Edinburgh to study medicine, then to Cambridge to study for the priesthood.

Then came his lucky break. Captain Robert Fitzroy was ordered by the Admiralty to take HMS Beagle, a small brig, to South America and beyond to survey the coastline to make it safer for shipping. He was only 26, came from an aristocratic family – his father was General Lord Fitzroy -  and asked that a suitable companion accompany him, someone with whom he could take his meals and converse, since the rest of the crew were very young and uneducated.

Darwin was the third choice, after his tutor, who was not interested, and a professor of botany who preferred to become vicar of Bottisham, but who recommended him; he could pursue his interest in natural history and Fitzroy would have a companion, an intelligent 23 year-old and a keen collector.

The voyage lasted five years, they went all around the world and Darwin spent many weeks ashore in various places, particularly in South America and the Galapagos Islands, where the Beagle stopped for surveying or to take on provisions.

Wherever he found himself he collected rocks, fossils, animals and plants, thousands of them and had them crated up and sent back to England whenever he came across an England-bound ship. He was meticulous.

Every item was annotated with description, drawings and detailed location. On his travels he noted variations among the same species and sometimes found it difficult to determine whether a variety was really a different species, or whether a new species‚ was merely a variety of a known species.

When he arrived home he found almost thirty large crates waiting for him containing thousands and thousands of specimens.

When Darwin unpacked his thousands of specimens he realized he had many years of work ahead identifying and annotating them and placing the plants and animals in their families. He had no eureka moment‚ but after some years of studying his specimens he realized that living things that were currently alive had not always existed but had evolved from earlier animals or plants.

He had observed earthquakes and volcanic eruptions in South America, realised that the earth could move drastically, displacing rocks and even mountains, which explained the oysters found on the mountaintop.

Based on that evidence he had what is probably the most important single idea that one man has ever had. The deep-rooted belief that the world and all its contents had been created some thousands of years earlier cannot be over emphasised and right up to the very middle of the nineteenth century this was the explanation of how the world began. 

Darwin assembled his specimens and spent twenty years writing up his notes which he published from time to time in scientific journals, and published his ship’s journal as a book, The Voyage of the Beagle.

By meticulous observations of small variations within and between species he realised that species had not been spontaneously created but that one species had evolved from another, like the branches of a tree, and that this process had taken not thousands but tens of millions of years.

But by what mechanism?  He examined his evidence and came to the conclusion that all living things, plants and animals both, were engaged in a constant struggle for existence, either to obtain sufficient food or to escape predators.

Those best fitted to adapt to changing conditions survived.  He noticed that members of the same species were not identical, there were small variations, and that when a variation in offspring occurred that was favourable to that organism, those with the variation gradually prevailed whilst those without disappeared or remained as a separate species, a process that he called

natural selection‚ which takes tens of thousands of generations.

Fish evolved into amphibians, amphibians to reptiles, reptiles to birds. Some of the original species continued to live alongside the new species, while others died out.

We still have amphibians alongside reptiles, but dinosaurs, pterodactyls and woolly mammoths have disappeared.

He was urged to publish his findings and his theory, but he wanted to consolidate his findings and was a little nervous of the outcome of publication which would be contrary to religious doctrine. Finally, in 1859, he published his findings in a book On the Origin of Species‚ and the rest, as they say, is natural History.