Linkage maps and phenotypic data for Bainbridge et al. 2020

Limited genetic parallels underlie convergent evolution
of quantitative pattern variation in mimetic butterflies Mimetic
systems allow us to address the question of whether the same genes control
similar phenotypes in different species. Although widespread parallels
have been found for major effect loci, much less is known about genes that
control quantitative trait variation. In this study, we identify and
compare the loci that control subtle changes in the size and shape of
forewing pattern elements in two Heliconius butterfly co-mimics. We use
quantitative trait locus (QTL) analysis with a multivariate phenotyping
approach to map the variation in red pattern elements across the whole
forewing surface of Heliconius erato and Heliconius melpomene. These
results are compared to a QTL analysis of univariate trait changes, and
show that our resolution for identifying small effect loci is somewhat
improved with the multivariate approach, but also that different loci are
detected with these different approaches. QTL likely corresponding to the
known patterning gene optix were found in both species but otherwise, a
remarkably low level of genetic parallelism was found. This lack of
similarity indicates that the genetic basis of convergent traits may not
be as predictable as assumed from studies that focus solely on Mendelian
traits.