Origin and Evolution of Exaggerated Traits
Some groups of organisms exhibit a remarkable diversity of forms. Conventional evolutionary theory attempts to explain this diversity through the accumulation of small changes over long periods of time. However, some traits are known to undergo rapid evolutionary change and exhibit extreme variation among species, often as a result of sexual selection, in which only a subset of males mate with females as a consequence of traits they possess. Such exaggerated traits provide an opportunity to determine the genetic and ecological factors that accompany rapid and extreme phenotypic evolution, and therefore to gain fundamental insights into how novel traits arise and diversify over evolutionary time.
With the advent of new sequencing technology, it has become possible to obtain the genomic sequence of almost any organism in a short amount of time. Through comparison with related model organisms, it is also possible to identify changes in the genome that could permit or influence the development of novel traits. The aim of this focus group is to use bioinformatic techniques and apply the comparative method to several groups of organisms, including species of fish, birds, and flies, in which there are annotated genomes as well as new genomic data from one or more non-model species that exhibit novel morphological diversity, such as bright coloration, extreme modifications of the head, or unusually long sperm. Questions of particular interest will focus on the role of gene duplication in the potential expression and perception of exaggerated traits, the role of sex chromosomes in influencing the expression and evolution of such traits, and the degree to which genomic conflicts created by self-replicating elements, such as transposable elements, may contribute to the evolution of morphological diversity by facilitating genomic change and novel gene function.
Gerald S. Wilkinson