Saturday, June 20, 2009

Review of Charles Darwin’s On the Origin of Species

Charles Darwin has rarely been bigger. In the midst of the 200th anniversary of his birth and the 150th anniversary of the Origin, there is little doubt as to the continued relevance of his ideas regarding evolution and natural selection. Yet a lot has changed since the original publication of the Origin; the advances made in the mid-20th century towards a modern synthesis connected Mendelian principles of inheritance to Darwin’s work thus bolstering the field of evolutionary biology. In light of such developments, the question remains: do Darwin’s ideas, in their original form, have any worth today? Can one still derive some sort of value from reading the Origin outside of pure historical value? I would argue yes. Darwin’s On the Origin of Species is a beautifully written and curiosity-packed piece of work; despite the aging of some of the ideas, just reading about how Darwin develops his careful argument for the validity of evolution is worth the price of admission.

The argument of the Origin, which is that species are not immutable and are subject to the laws of natural selection, can be thought of as divided into two parts. The first part of the argument, chapters 1 through 5, are the chapters in which Darwin sets up the guiding principles of his theory of evolution. He draws upon Malthusian principles to describe the struggle for existence that characterizes all life and how it necessitates the role of natural selection in favoring those individuals best adapted for the struggle. He also introduces the concept of inheritance of traits, as well as the laws of variation, both of which then play into Darwin’s own description of natural selection.

It is within this first part that Darwin establishes the basic pattern of his argument, which tries to mitigate the leap of faith readers at the time might have felt regarding evolution by arguing from the common towards the less common; Darwin uses common examples in everyday life to illustrate the viability of the largely unknown concepts that he introduces. For example, Darwin begins the Origin by discussing domestic breeding, man’s manipulation of variation by intentionally crossing different individuals within and between species. Darwin’s implicit assumption is that this is an example that has been acknowledged and seen as valid by most readers; from here he feels more comfortable then makes the transition from artificial selection to natural selection. It works; while the Origin in general requires a little bit of imagination to really understand the links Darwin makes, his unique brand of argument from example exemplifies how immediate and relevant the Origin feels when reading it, even today.

The second half of the Origin, in contrast, is an expansion of Darwin’s chapter of addressing difficulties; following chapter 6, the rest of the chapters mostly take one issue of contention that threatens the validity of Darwin’s argument – instinct, hybridization, the geological record, etc. – and systematically goes through and either disproves the relevance of the issue to Darwin’s theory or simply undermines the integrity of the issue. It is in this part of the Origin that Darwin becomes a bit uneven in terms of successfully addressing grievances; while certain issues like instinct are handled well and argued with fantastic examples (the instinct chapter in particular has really cool insights on the construction of honey comb by hive-bees), other issues, like the imperfection of the geological record, are more tenuous and see Darwin making riskier assertions. Darwin is no Lyell when it comes to discussing geology, yet he still manages to criticize the integrity of the field thoroughly in the quest to defend his theory of evolution. Overall, however, the second half of the book has many fascinating insights into how Darwin worked around the limitations of arguing with only the evidence of natural history to go off of, reinforcing the validity of the principles of evolution introduced in the first half of the book.

Despite the imperfections in Darwin’s argument, On the Origin of Species is a remarkable and well-structured account of how the evidence for evolution is all around us. While other scientists and theorists may have had the benefit of advances in evolutionary biology in explaining and justifying evolution to the masses, few of them have the mainstream accessibility and reverence for nature that Darwin brings to his nuanced writing and argumentative skills. So do pick up the Origin sometime and read it – not as some extended scientific dissertation, but as the account of a man genuinely awestruck by nature and understanding of the ways in which it works. Darwin’s ideas as purported in the Origin may not be completely right anymore, but they will always have value in their capturing of what it means to live in a world governed by evolution, and the liberation that comes with it.

--Andrew Plan

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