Getting “Lamarckian” right

Lamarck’s theory of evolutionary adaptation invokes the inheritance of adaptive responses that emerge by effort.  Over a century ago, this mechanism was rejected by geneticists familiar with results on mutation and inheritance, e.g., Cuenot (1909) rejects Lamarckian modification on the grounds that hereditary variants emerge suddenly, rather than being brought on gradually by use and disuse.

This topic would deserve no further comment, except that the false idea of a rebirth of a Lamarckian mode of evolutionary change has been stirred up repeatedly by contemporary scientists guided by the false dichotomy of Lamarck vs. Darwin.  


The buffet and the sushi conveyor

The return of mutationism to mainstream evolutionary biology is evident in the way mainstream articles now describe the role of mutation in evolution, in our reliance on mathematical models that evoke a mutationist view, and in evo-devo research programs that focus on identifying causative major-effect mutations.

This shift has happened in a kind of sub-conscious way, without commentary or reflection.  I’ll comment below on the reasons for that.

My main purpose here is to contrast way that the neo-Darwinian and mutationist views refer implicitly to two different regimes of population genetics evoked in two styles of self-service restaurant: the buffet and the sushi conveyor.


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