From “Perspectives evolutionary novelty and evo-devo: integrating explanatory approaches” special issue guest-edited by Ingo Brigandt.
Levels of Biological Organization and the Origin of Novelty
Version of Record online: 8 AUG 2011
Copyright © 2011 Wiley Periodicals, Inc.
Journal of Experimental Zoology Part B: Molecular and Developmental Evolution
Special Issue: Perspectives on Evolutionary Novelty and Evo-Devo
Volume 318, Issue 6, pages 428–437, September 2012
How to Cite
2012. Levels of biological organization and the origin of novelty. J. Exp. Zool. (Mol. Dev. Evol.) 318B:428–437.,
- Issue online: 30 AUG 2012
- Version of Record online: 8 AUG 2011
- Manuscript Accepted: 11 JUN 2011
- Manuscript Revised: 8 JUN 2011
- Manuscript Received: 12 JAN 2011
- NSERC of Canada. Grant Number: A5056
- SSHRC of Canada. Grant Number: 410-2008-0400
The concept of novelty in evolutionary biology pertains to multiple tiers of biological organization from behavioral and morphological changes to changes at the molecular level. Identifying novel features requires assessments of similarity (homology and homoplasy) of relationships (phylogenetic history) and of shared developmental and genetic pathways or networks. After a brief discussion of how novelty is used in recent literature, we discuss whether the evolutionary approach to homology and homoplasy initially formulated by Lankester in the 19th century informs our understanding of novelty today. We then discuss six examples of morphological features described in the recent literature as novelties, and assess the basis upon which they are regarded as novel. The six are: origin of the turtle shell, transition from fish fins to tetrapod limbs, origination of the neural crest and neural crest cells, cement glands in frogs and casquettes in fish, whale bone-eating tubeworms, and the digestion of plant proteins by nematodes. The article concludes with a discussion of means of acquiring novel genetic information that can account for novelty recognized at higher levels. These are co-options of existing genetic circuitry, gene duplication followed by neofunctionalization, gene rearrangements through mobile genetic elements, and lateral gene transfer. We conclude that on the molecular level only the latter category provides novel genetic information, in that there is no homologous precursor. However, novel phenotypes can be generated through both neofunctionalization and gene rearrangements. Therefore, assigning phenotypic or genotypic “novelty” is contingent on the level of biological organization addressed. J. Exp. Zool. (Mol. Dev. Evol.) 318B:428–437, 2012. © 2011 Wiley Periodicals, Inc.