Over at the New Scientist, Queen's University Belfast's Keith Bennett examines the burgeoning "chaos theory of evolution," which is supported by fossil records, climate data, and both modern and ancient DNA. According to Bennett, "the main response to major environmental changes is individualistic movement and changes in abundance, rather than extinction or speciation. ... The connection between environmental change and evolutionary change is weak, which is not what might have been expected from Darwin's hypothesis." He goes on to suggest that macroevolutionary change is non-linear in the same way that the "dynamics of the relationship between genotype and phenotype" are. In addition, Bennett writes, as mutations occur continually and can be passed on to progeny and because "a change of a single base of an organism's DNA might have no consequence" or it could have devastating effects, a "small change can have far-reaching and unpredictable effects — the hallmark of a non-linear system." Overall, Bennett suggests, these and other phenomena provide support for the theory that "macroevolution may, over the longer-term, be driven largely by internally generated genetic change, not adaptation to a changing environment."
Genotype-Phenotype Correlations Confer 'Chaotic' Evolution
Oct 19, 2010