The heritable epigenetic modifications that affect gene expression, as used by Jablonka and Raz ([2009]), are called ‘epialleles’. Darwin's theory of natural selection helped to convince 990–1) to refer to the Mendelian ‘unit-factors’ in the gametes and to distinguish them from the phenotype, biologists could finally locate the genes precisely in DNA molecules. But it does not necessarily follow from this that the alternative approach represents a revolution in current gene-centric evolutionary theory. [2015]). This latter point can be illustrated by some studies showing that RNA is able to ferry information for multiple generations (Costa [2008]; Rechavi et al. Doolittle, W. Ford 2000. LUA is defined as most recent organism from which all organisms now living on Earth descend (some 3.5 to 3.8 billion years ago, in the Archean era). 3 See also (Pigliucci and Muller [2010]; Noble et al. [2006]); see also (Jablonka [2006]). Further research demonstrated that the inheritance pattern is caused by the RNA molecules manufactured by the mutant KIT gene in the male parent being delivered via the sperm to the offspring (Rassoulzadegan et al. Lederberg J. Copyright © 1993-1997 by It is, at least on first sight, an example of megaevolution by big jumps. Genes as Followers in Evolution: A Post-synthesis Synthesis? The second challenge stems from the inheritance of environmentally induced phenotypes via epigenetic modifications, which is claimed to provide evidence for non-random non-genetic variations, something that is ruled out by the MS. A comparative analysis of the Darwin-Wallace papers and the development of the concept of natural selection. For example, when experimenting on a strain of heterozygote mice with a mutant allele of the KIT gene that produces a white tail tip, researchers found that most of their offspring that inherited two wild-type alleles still had a white tail tip (Rassoulzadegan et al. addition Darwin advocated natural selection as a mechanism of evolution. Friedman, Matt 2008. No new These and similar examples strongly indicate that nuclear DNA cannot be the sole heritable material influencing the production of phenotypic variations. We must assess the extent to which current evolutionary theory, with its commitment to the DNA-based genetic inheritance, needs to be revised to take into account epigenetic inheritance. [41][42], Once symbiosis was discovered in lichen and in plant roots (rhizobia in root nodules) in the 19th century, the idea arose that the process might have occurred more widely, and might be important in evolution. Diversity, evolution, and inheritance. What once was called embryology played a modest role in the evolutionary synthesis,[57] mostly about evolution by changes in developmental timing (allometry and heterochrony). The structure of evolutionary theory. Similarly, Haig ([2012], p. 461), while defending gene selectionism, defines the environment as ‘all parts of the world that are shared by the alternatives being compared’. Stent ([1977]), a molecular biologist, criticized Dawkins for holding a notion of gene that ‘denatures the meaningful and well-established central concept of genetics into a fuzzy and heuristically useless notion’. Standard work providing general history of the idea of evolution from Antiquity to the late 20th century. This extension, as we have shown in Section 2.1, corresponds well to formal evolutionary theory and thus also to the gene-centric tenet of the MS. On the other hand, as we will argue in the following section, given our framework, evolutionary theory can accommodate mechanisms of epigenetic inheritance without a profound conceptual change. We argue that once one realizes that the evolutionary gene can also encompass epialleles, this claim does not threaten current evolutionary theory. High frequency of horizontal gene transfer in the oceans. It thus makes Mayr’s distinction between developmental (proximate) and evolutionary (ultimate) causes less clear-cut than it was once thought to be (Uller [2008]; Danchin and Pocheville [2014]; Scholl and Pigliucci [2014]). In other circumstances, they explicitly refer to genes as pieces of DNA.