160th anniversary of the presentation of "On the tendency of Species to form Varieties"
Today marks the 160th anniversary of the presentation of papers by Charles Darwin and Alfred Russel Wallace outlining the theory of evolution by natural selection at a meeting at the Linnean Society in 1858.
Unfortunately, neither of the two were present. Darwin was unwell and still grieving following the death of his son and Wallace was away in the Moluccas in Indonesia.
On 18 June 1858 Darwin had received a letter from Wallace containing an essay entitled “On the tendency of species to depart indefinitely from the Original type” which formulated the same hypothesis that Darwin had worked on for the last twenty years but had never published. Darwin sent this to Scottish Geologist Sir Charles Lyell as requested by Wallace and also informed his close friend and botanist/explorer Joseph Dalton Hooker of what had happened.
Lyell and Hooker were familiar with Darwin’s views by this point and Hooker had read his original manuscript. It was thanks to these two that Darwin was persuaded not to publish Wallace’s essay without publishing his own long-withheld manuscript. Darwin left the matter in the hand of Lyell and Hooker who presented the papers just in time for an extra meeting held at the Society.
The two wrote a joint letter to the Secretary, J. J Bennet, which arrived only the day before the meeting. It contained:
- Extracts from the first part of a MS. work on Species by Darwin that also included extracts from the second chapter headed “On the Variation of Organic Being in a State of Nature; on the Natural Means of Selection; on the Comparison of Domestic Races and true Species” of which both Hooker and Lyell intended to read at the Society.
- Abstract from a letter from Darwin to Prof. Asa Gray, Boston, U .S. dated September 5th 1857 highlighting his unaltered views.
- “On the Tendency of Varieties to depart indefinitely from the Original Type” by Alfred Russel Wallace.
As it was customary to not receive the agenda in advance, these papers that were read by the Secretary J. J Bennet were a complete surprise to everyone attending. In a letter written from Hooker to Charles Darwin’s son, Francis Darwin, 28 years after the meeting, he describes how the room was awestruck and completely silent. There was a lack of discussion about the papers which he put down to the subject being too novel and ominous.
Thomas Bell, the president of the Society at the time, had no inkling that this was the start of a paradigm shift. In his Presidential address in May 1859 reviewing the previous year he said
The year which has passed… has not, indeed, been marked by any of those striking discoveries which at once revolutionise, so to speak, the department of science on which they bear.
It was only when Darwin published his Origins of Species by means of natural selection, a year later that the significance of this momentous occasion became evident.
Eleanor Marshall, Intern