Evolution of larval morphology in flies:: get in shape with shavenbaby

The morphological features of animal species are their most obvious genetic characteristics. However, how a morphological trait becomes organized during development and how it evolves to create novel features are still unknown. The diversity of trichome patterns, which characterize the external appearance of fly larvae, has emerged as a model to understand the genetic basis of morphological diversification during evolution. In this article, we focus on recent findings showing that all independent cases of evolution of larval-trichome pattern that have been studied in dipteran result from changes in the same molecular mechanism. These results suggest that a few regulatory factors govern morphological modules during development and that the diversification of their expression represents a rich source for the evolution of morphology.