Saturday, October 01, 2016

Extending evolutionary theory? - Kevin Laland

I will be attending the Royal Society Meeting on New trends in evolutionary biology: biological, philosophical and social science perspectives. I'll post each of the abstracts and ask for your help in deciding what question to pose to the speakers. Here's the abstract for Kevin Laland's talk on The middle ground between artificial and natural selection: niche construction as developmental bias.

Organisms modify and choose components of their local environments. This ‘niche construction’ is subject to extensive research across several academic fields. It is well appreciated that niche construction can alter ecological processes, modify natural selection, and contribute to inheritance through ecological legacies. However, niche construction is not usually regarded as an evolutionary process, probably because traditional evolutionary accounts restrict evolutionary processes to phenomena that directly change gene frequencies (e.g. selection, mutation, drift).

Alternative perspectives can be of value if they generate novel predictions, open up new lines of enquiry, or generate new insights. The niche-construction perspective within evolutionary biology provides an alternative account of the causal relations underlying adaptation, a stance that has already led to a number of valuable insights. Here I suggest that there is heuristic value in regarding niche construction as an evolutionary process, on the grounds that it initiates and modifies the selection acting back on the constructor (and other species) in an orderly and directional manner. As a consequence, niche construction co-directs adaptive evolution by imposing a statistical bias on selection (an externally expressed form of developmental bias).

I illustrate how niche construction can generate developmental bias by comparing it with artificial selection, where I suggest it occupies the middle ground between artificial and natural selection. This perspective has heuristic value for the evolutionary biologist, leading to testable predictions related to: (i) trait evolution, including the evolution of sequences of traits and parallel evolution; (ii) responses to natural selection in the wild; and (iii) biodiversity.
I don't get this emphasis on niche construction. Biologists have been talking about how organisms modify the environment for one hundred years or more. I can see how an understanding of particular examples, such as the increase in oxygen levels due to the evolution of water splitting reactions, can provide insight into the history of life but how does that fit into evolutionary theory?

I don't have any questions for Kevin Laland. I'm anxious to see how the people at this meeting view niche construction.


4 comments :

  1. General relativity showed that space is not a passive container for interactions among material objects. A focus on niche construction illustrates how the environment is not a passive container for evolutionary processes. Can one develop a "general relativity" version of evolutionary theory that includes the environment as an active participant?

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    1. I'm no biologist, but it seems to me the idea of "the environment as an active participant" in shaping life is a description of the process called natural selection. That idea has been around for quite a while, already.

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  2. Yeah, basically, the traditional view of a niche, as put forth by Hutchinson (multidimensional space) was a space that a species was fit into by the processes of selection, drift, and abiotic factors. Laland and colleagues argue that animals are not passively pushed into a niche, but actively create their niche, often through things like learning/innovation (which is Laland's background)

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  3. I read Kevin's 2003 book on niche construction earlier this year. I think it makes reasonable sense, though I have some disagreements when it comes to terminology and emphasis. Kevin doesn't dispute people have been looking at modifications of environments by organisms for over a hundred years (think about Darwin's earthworms). Instead he argues that there's been no proper theoretical framework for such work. Many evolutionary models have no causal arrow going from organism to environment.

    As to the relationship to evolutionary theory - one major point of contact is environmental inheritance. Organisms inherit their environments from their ancestors as well as their genes. Rabbits inherit their warrens, gum bacteria inherit plaques and cavities - and so on. Environmental inheritance may not have the same high fidelity transmission that DNA enjoys, but there's inheritance with variation and selection of these environmental variables. They evolve - and co-evolve with the organisms involved.

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