Events – Monday 12 February 2018, 5:00 pm
Each year Humanists and other freethinkers celebrate Charles Darwin’s contribution to our understanding of the variety of life forms. We do this on 12 February – Darwin’s birthday – known as International Darwin Day.
The contribution Darwin made, like other rare people, e.g. Copernicus, Newton, has totally changed the way we humans perceive our place in the universe. His contribution enables us to see that all life forms, including humans, are naturally evolved rather than specially created.
How was Darwin able to make such a world-changing contribution?
Breakthroughs in knowledge are typically made by those with enquiring minds and the opportunity to investigate what interests them. Darwin is a good example; as a boy he had a great interest in animals and plants that led him to develop excellent observational skills. As a young man he had the unique opportunity to spend five years (1831–36) travelling around the world on the HMS Beagle. As the ship’s naturalist he made extensive observations and collected innumerable specimens, especially from South America, some Pacific Islands and Australia.
On his return to England, Darwin was able to leisurely study his notes and specimens, and write a series of papers and books. His family circumstances guaranteed him a comfortable income, so he was able to marry (into the Wedgewood family), raise a family and provide for their needs, while working on his ground-breaking ideas.
What was his contribution?
Humans had long puzzled over the huge variety of life forms and how each seemed so well suited to its particular environment. As long ago as the Ancient Greeks a few thinkers had proposed that life had begun as simple forms and then developed or ‘evolved’ into more complex forms. This idea of life evolving was occasionally speculated about, but after the foundations of geology as a study were laid in the late 1700s, many observers noted the sedimentary strata, plus presence of fossils. This led to the realisation the Earth was far older than had previously been believed.
While suggesting that living things had come to their present forms through evolution was easy to propose, explaining how this might occur had proved elusive, until Darwin and Alfred Wallace, another naturalist, conceived the mechanism as ‘natural selection’. Papers by both men were presented at a meeting of the Linnean Society (London) on 1 July 1858. Neither attended this meeting. Darwin was at home in Downe, Wallace 12,000 miles away collecting in the Moluccas.
By drawing on keen observational skills and their travels around the world, both Darwin and Wallace independently conceived of a mechanism for how life forms became well adapted to their particular environments. They called this mechanism ‘natural selection’. What they meant was that ‘nature’ selected which individuals would survive and go on to reproduce their kind. The selected individuals would typically possess advantageous features that aided their survival, such as colour for camouflage, greater speed to catch prey or escape predators.
Why do we honour Darwin rather than Wallace?
This is a clear case of not so much what you know, as who you know. Through his father and grandfather Darwin had credibility in scientific and social circles. He also was well regarded by his scientific colleagues who aided the promotion of his ideas. Wallace by contrast was a journeyman naturalist who always needed to earn a living from his own endeavours, mostly collecting specimens in remote parts of the globe.
In 1842 Darwin began making notes on natural selection, referring to these as ‘my species theory’. Once the two papers were presented at the Linnean Society, both Darwin and Wallace had an equal claim on proposing ‘natural selection’. However, Darwin’s scientific friends urged him to publish the ‘book’ he had been quietly working on for several decades.
Darwin worked feverishly assembling a convincing argument for natural selection. He referred to fossils as early ancestors of current species. And by making a close study of artificial selection, such as occurred when humans selectively bred some individuals for the features they desired, e.g. greater milk production, bigger wheat ears, tastier fruit, Darwin was able to compare artificial selection with natural selection.
Most people understood artificial selection, so Darwin tried to show them it was not such a big leap to understand natural selection. By using everyday examples of artificial selection, Darwin was able to make natural selection comprehensible.
In late 1859 Darwin published the first edition of his opus magnum, On the Origin of Species by Means of Natural Selection. It was this book that convinced Darwin’s scientific colleagues of the validity of natural selection. As each new edition of this book was published, Darwin continually re-wrote sections for greater clarity.
On the Origin of Species, as it was eventually titled, is a ground-breaking book. It is still essential reading for those who want a full appreciation of what a remarkable grasp Darwin had of how species change and so evolve into new forms. Hence our celebration of International Darwin Day.
Where and When
Join us at 5:00 pm on Monday 12th February at Studley Park, Kew, in Melbourne (under the shelter by the electric barbecues) for a picnic (BYO) to celebrate the enormous positive impact Charles Darwin had on the world.