Table of Contents
International Journal of Evolutionary Biology
Volume 2012, Article ID 490894, 8 pages
http://dx.doi.org/10.1155/2012/490894
Review Article

The Evolution of Novelty in Conserved Gene Families

Department for Evolutionary Biology, Max Planck Institute for Developmental Biology, Spemannstraße 37, 72076 Tübingen, Germany

Received 16 March 2012; Accepted 23 April 2012

Academic Editor: Frédéric Brunet

Copyright © 2012 Gabriel V. Markov and Ralf J. Sommer. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

One of the major aims of contemporary evolutionary biology is the understanding of the current pattern of biological diversity. This involves, first, the description of character distribution at various nodes of the phylogenetic tree of life and, second, the functional explanation of such changes. The analysis of character distribution is a powerful tool at both the morphological and molecular levels. Recent high-throughput sequencing approaches provide new opportunities to study the genetic architecture of organisms at the genome-wide level. In eukaryotes, one overarching finding is the absence of simple correlations of gene count and biological complexity. Instead, the domain architecture of proteins is becoming a central focus for large-scale evolutionary innovations. Here, we review examples of the evolution of novelty in conserved gene families in insects and nematodes. We highlight how in the absence of whole-genome duplications molecular novelty can arise, how members of gene families have diversified at distinct mechanistic levels, and how gene expression can be maintained in the context of multiple innovations in regulatory mechanisms.