The formalism used to describe evolutionary change in a multilevel setting can be used equally to re-describe the situation as one where all the selection occurs at the individual level. Thus, whether multilevel or individual-level selection occurs seems to be a matter of convention rather than fact. Yet, group selection is regarded by some as an important concept with factual rather than conventional elements. I flesh out an alternative position that regards groups as a target of selection in a way (...) that is not merely definitional fiat and provide a theoretical basis for this position. (shrink)

In this article we examine the “phenotype” concept in light of recent technological advances in Genome-Wide Association Studies . By observing the technology and its presuppositions, we put forward the thesis that at least in this case genotype and phenotype are effectively coidentifled one by means of the other. We suggest that the coidentiflcation of genotype-phenotype couples in expression-based GWAS also indicates a conceptual dependence, which we call “co-deñnition.” We note that viewing these terms as codeflned runs against possible expectations, (...) viz., that genotypes and phenotypes could ultimately be expressed independently from one another. In addition, the co-definition of genotypes and phenotypes in this context emphasizes the correlative character of both genotypes and phenotypes in GWAS. (shrink)