Natural Selection: Evolving evolvability

TL;DR: In this paper, the origins of many aspects of biological diversity, from gene-structural embellishments to novelties at the phenotypic level, have roots in nonadaptive processes, with the population-genetic environment imposing strong directionality on the paths that are open to evolutionary exploitation.

TL;DR: The ability to adapt to marginal habitats, in which survival and reproduction are initially poor, plays a crucial role in the evolution of ecological niches and species ranges as mentioned in this paper, but adaptation to marginal habitat may be limited by genetic, developmental, and functional constraints, but also by consequences of demographic characteristics of marginal populations, which makes them demographically and genetically dependent on core habitats and prone to gene flow counteracting local selection.

TL;DR: The concept of evolvability, and the increasing theoretical and empirical literature that refers to it, may constitute one of several pillars on which an extended evolutionary synthesis will take shape during the next few years, although much work remains to be done on how evolVability comes about.

TL;DR: This paper reviews what has been learned about canalization since Waddington and explains why different forms of selection can favor canalization, and in terms of genetic redundancy, modularity, and emergent properties of gene networks and biochemical pathways, it is concluded that there are still serious problems with unambiguously demonstrating canalization.

TL;DR: It is suggested that recent views on the nature of the developmental process make it easier to understand how the genotypes of evolving organisms can respond to the environment in a more co-ordinated fashion.

TL;DR: It is reported that when Drosophila Hsp90 is mutant or pharmacologically impaired, phenotypic variation affecting nearly any adult structure is produced, with specific variants depending on the genetic background and occurring both in laboratory strains and in wild populations.

TL;DR: The effect of sex and recombination in breaking down negative correlations between favorable variants at different genetic loci, which increases the efficiency of natural selection, is likely to be a major factor favoring their evolution and maintenance.

TL;DR: Whether high mutation rates might play an important role in adaptive evolution is considered, as models of large, asexual, clonal populations adapting to a new environment show that strong mutator genes can accelerate adaptation, even if the mutator gene remains at a very low frequency.