Neo-Sex Chromosome Evolution in Treehoppers Despite Long-Term X Chromosome Conservation.

Sex chromosomes follow distinct evolutionary trajectories compared to the rest of the genome. In many cases, sex chromosomes (X and Y or Z and W) significantly differentiate from one another resulting in heteromorphic sex chromosome systems. Such heteromorphic systems are thought to act as an evolutionary trap that prevents subsequent turnover of the sex chromosome system.

Acute and Long-Term Consequences of Co-opted doublesex on the Development of Mimetic Butterfly Color Patterns.

Novel phenotypes are increasingly recognized to have evolved by co-option of conserved genes into new developmental contexts, yet the process by which co-opted genes modify existing developmental programs remains obscure. Here, we provide insight into this process by characterizing the role of co-opted doublesex in butterfly wing color pattern development. dsx is the master regulator of insect sex differentiation but has been co-opted to control the switch between discrete nonmimetic and mimetic patterns in Papilio alphenor and its relatives through the evolution of novel mimetic alleles.

Detecting signatures of selection on gene expression.

A substantial amount of phenotypic diversity results from changes in gene expression levels and patterns. Understanding how the transcriptome evolves is therefore a key priority in identifying mechanisms of adaptive change. However, in contrast to powerful models of sequence evolution, we lack a consensus model of gene expression evolution.