O que evolucionistas estão dizendo sobre a ineficácia da seleção natural como mecanismo evolucionário

terça-feira, dezembro 11, 2012

Michael Lynch:

the uncritical acceptance of natural selection as an explanatory force for all aspects of biodiversity (without any direct evidence) is not much different than invoking an intelligent designer (without any direct evidence). True, we have actually seen natural selection in action in a number of well-documented cases of phenotypic evolution (Endler 1986; Kingsolver et al. 2001), but it is a leap to assume that selection accounts for all evolutionary change, particularly at the molecular and cellular levels. The blind worship of natural selection is not evolutionary biology. It is arguably not even science. Natural selection is just one of several evolutionary mechanisms, and the failure to realize this is probably the most significant impediment to a fruitful integration of evolutionary theory with molecular, cellular, and developmental biology.

– Michael Lynch, The Origins of Genome Architecture (Sinauer, 2007, pp. 368-9)

Marc Kirschner and John Gerhart:

There are limits on what selection can accomplish. We must remember that it merely acts as a sieve, preserving some variants and rejecting others; it does not create variation. If genetic change were random, what could ensure that enough favorable phenotypic variation had taken place for selection to have produced the exquisite adaptation and variety we see on the earth today? At various times, biologists thought that genetic change must be directed in some way to produce enough of the appropriate kinds of phenotypic variation. If selection were presented with a preselected subset of variants, that might greatly facilitate evolutionary change. Or if the organism generated just the right variants, selection might not be needed at all. Thus, the efficacy of selection would depend on the nature of phenotypic variation…Is genetic variation purely random, or is it in fact biased to facilitate evolutionary change?

– Marc Kirschner and John Gerhart, The Plausibility of Life: Resolving Darwin’s Dilemma (Yale, 2005, p. 13)

Eric Davidson:

Of the first of these approaches (e.g., Hoekstra and Coyne, 2007), I shall have nothing to say, as mechanistic developmental biology has shown that its fundamental concepts are largely irrelevant to the process by which the body plan is formed in ontogeny. In addition it gives rise to lethal errors in respect to evolutionary process. Neo-Darwinian evolution is uniformitarian in that it assumes that all process works the same way, so that evolution of enzymes or flower colors can be used as current proxies for study of evolution of the body plan. It erroneously assumes that change in protein coding sequence is the basic cause of change in developmental program; and it erroneously assumes that evolutionary change in body plan morphology occurs by a continuous process. All of these assumptions are basically counterfactual. This cannot be surprising, since the neo-Darwinian synthesis from which these ideas stem was a pre-molecular biology concoction focused on population genetics and adaptation natural history, neither of which have any direct mechanistic import for the genomic regulatory systems that drive embryonic development of the body plan.

– Eric Davidson, “Evolutionary bioscience as regulatory systems biology,” Developmental Biology 357 (2011):35-40.

Andreas Wagner:

…we know few of the principles that explain the ability of living things to innovate through a combination of natural selection and random genetic change. Random change by itself is not sufficient, because it does not necessarily bring forth beneficial phenotypes. For example, random change might not be suitable to improve most man-made, technological systems. Similarly, natural selection alone is not sufficient: As the geneticist Hugo de Vries already noted in 1905, ‘natural selection may explain the survival of the fittest, but it cannot explain the arrival of the fittest’. Any principle of innovation needs to explain how novel, beneficial phenotypes can originate. In other words, principles of innovation are principles of phenotypic variability.

– Andreas Wagner, “The molecular origins of evolutionary innovations,” Trends in Genetics 27 (2011):397-410



Por que os autores de livros didáticos de Biologia do Ensino Médio, na sua abordagem da teoria da evolução de Darwin, não mencionam esses questionamentos sobre a eficiência da seleção natural como um mecanismo evolucionário??? O nome disso é DESONESTIDADE ACADÊMICA, 171 EPISTÊMICO.