From The Character Concept in Evolutionary Biology, G.P. Wagner, editor. Reprinted with permission. © 2000 by Academic Press, San Diego.
Homologies of process and modular elements of embryonic construction†
Article first published online: 30 MAR 2001
Copyright © 2001 Wiley-Liss, Inc.
Journal of Experimental Zoology
Volume 291, Issue 1, pages 1–12, 15/30 April 2001
How to Cite
Gilbert, S. F. and Bolker, J. A. (2001), Homologies of process and modular elements of embryonic construction. J. Exp. Zool., 291: 1–12. doi: 10.1002/jez.1
- Issue published online: 26 DEC 2002
- Article first published online: 30 MAR 2001
- Manuscript Accepted: 6 NOV 2000
- Manuscript Received: 18 MAY 2000
There are several signal transduction pathways that integrate embryonic development. We find that both within species and between species, these pathways constitute homologous modules. The processes, themselves, can be considered homologous, just as structures can be considered homologous. Just like vertebrate limbs, these pathways are composed of homologous parts (in this case, the proteins of the pathway) that are organized in homologous ways. These pathways are conserved through evolutionary time, and they undergo descent with modification. Such homologies of processes become critical to the discussion of evolution and development when we consider (1) that evolution depends on heritable changes in development, (2) that development is modular such that different modules can change without affecting other modules, (3) that modules can be co-opted into new functions, and (4) that modules depend on intercellular communication. J. Exp. Zool. (Mol. Dev. Evol.) 291:1–12, 2001. © 2001 Wiley-Liss, Inc.