Sunday, 8 February 2009

Blog for Darwin: What Darwin didn’t know but suspected.

As the Bicentenary of Darwin’s birth approaches, I have revisited 'On the Origins of Species'. Like many people, I first picked it up at the start of my undergrad and found it to be truly inspirational. However, reading it several years later, with the benefit of my research career and now much more extensive knowledge of evolutionary processes, it amazed me the level of insight Darwin had without the molecular approaches and techniques that wouldn’t start becoming available for some 100 years. Darwin, with the same observational approaches that seemingly were available to mankind since we started to observe our environment, came up with the revolutionary idea of evolution, not only explaining how all organisms arrived at their current state but also allowing us to be intellectually empowered atheists, explaining in some degree where all organisms came from.

Here are a few examples

“… I presume, say that, after a certain unknown number of generations, some bird had given birth to a woodpecker, and some plant to mistletoe, and that these had been produced perfect as now we see them; but this assumption seems to me to be no explanation, for it leaves the case of conditions of organic beings to each other and to their physical conditions of life, untouched and unexplained.”

Here Darwin dismiss’ creationism and even to some extent and saltationism; offering up gradual changes as the method for for generating new species, rather than a complete change within a single generation.

“I am capable, that the view which most naturalist entertain, and which I formally entertained-namely, that each species has been independently created-is erroneous. I am fully convinced that species are not immutable; but that those belonging to what are called the same genera are lineal descendants of some other and generally extinct species, in the same manner as the acknowledged varieties of any one species are descendants of that species.”

This is probably on of the most important statements; here for the first time we are seeing the theory of natural selection laid bare.

Darwin also comments on the importance of sexual selection and how it confers somewhat inhibitory appendages, but the level of hindrance correlates with the fitness of the organism, the role of two organisms in the mating of hermaphroditic species. And talks about the importance of inheritance without the concept of the gene and Mendelian inheritance.

“it has been disputed at what period of life the causes of variability, whatever they may be, generally act; whether during the early or late period of development of the embryo, or at least the instant of conception. ….But I am strongly inclined to suspect that the most frequent cause of variability may be attributed to the male and female reproductive elements having been affected prior to the act of conception.”

Anyone can point out mistakes within the Darwin’s writings, after all it's like trying to put a jigsaw together without knowing what it looks like or even having all the pieces. For example, Darwin could not comment or conceive the intricate processes that were to be discovered in the following 150 years; such as the importance of neutral selection, endosymbiosis, hybridization to the creation of new species. But Darwin does give a general nod to all the clear methods of speciation that we understand today allopatric, peripatric, parapatric and sympatric. Without his important works we would not have the many schools of evolutionary thought that exist today: Punctuationalists, Saltationists, and Neo-Darwinists and in the early days Lemarkists to name but a few. As with the Modern synthesis, the coming together of evolutionary theories today will revolutionize our understanding, and admittedly allow for a number of 'Darwin was wrong' articles to be published, but on the whole, will leave us better placed to answer the question; where did life come from? We have much to be thankful for, the initial works of Darwin, Wallace and their predecessors have given us a starting point to explore the origin of life with a scientific method, something that may not have happened for sometime had their abstracts not been read at Linnean Society of London on that first day of July 1858. And so we must also remember as well that 'The origin of the species' was written not as fact or as an immutable idea but as simply an idea to be built upon by the succesive generations; as it has been. And it makes me glad that within many of our research careers we will all add to it in someway or another, getting closer to the truth that is evolution.

1 comment:

James Hale said...

Sorry this is a re-post i wanted to tweek it a little.