Genetic Variation in Sexual Size Dimorphism Is Associated with Variation in Sex-Specific Plasticity in .

AbstractThe difference in body size between females and males, or sexual size dimorphism (SSD), is ubiquitous, yet we have a poor understanding of the developmental genetic mechanisms that generate it and how these mechanisms may vary within and among species. Such an understanding of the genetic architecture of SSD is important if we are to evaluate alternative models of SSD evolution, but the genetic architecture is difficult to describe because SSD is a characteristic of populations, not individuals. Here, we overcome this challenge by using isogenic lineages of to measure SSD for 196 genotypes.

Genetic variation of morphological scaling in Drosophila melanogaster.

Morphological scaling relationships between the sizes of individual traits and the body captures the characteristic shape of a species, and their evolution is the primary mechanism of morphological diversification. However, we have almost no knowledge of the genetic variation of scaling, which is critical if we are to understand how scaling evolves. Here we explore the genetics of population scaling relationships (scaling relationships fit to multiple genetically-distinct individuals in a population) by describing the distribution of individual scaling relationships (genotype-specific scaling relationships that are unseen or cryptic).