2009 has been the 200th anniversary year of Charles Darwin’s birth, and the 150th anniversary of the publication of On the Origin of Species. There have been a number of excellent articles and films about Darwin’s life and work which are worth following up. In the February 2009 issue of Journal of Biology, Jonathan Howard discusses why Darwin didn’t manage to discover what Mendel did, namely the particulate nature of inheritance (Howard 2009). He did some plant-crossing experiments which came extremely close to Mendel’s key result, but did not see the significance of the proportions produced. Howard argues that Darwin was so committed to the idea of gradual, quantitative change (something he got from his background as a geologist, in particular a geologist of the school known as uniformitarianism, which saw geological change as arising from continual tiny changes rather than sudden catastrophes), that he could not relate to the idea of genes being discrete and having potentially discontinuous effects on variation. Indeed, for many decades after Darwin, the ‘Mendelians’ who emphasised distinct particles of inheritance, and the Darwinians who saw variation as continuous, were perceived as opposed to each other. It was only the New Synthesis that sorted this out.

Howard, J. C. (2009). Why didn’t Darwin discover Mendel’s laws? Journal of Biology 8: 15
Open access at: http://jbiol.com/content/8/2/15 [DOI: 10.1186/jbiol123]