Developmental Biology

20 Jan 2004 08:50

The science formerly known as embryology.

Self-organization and pattern formation --- physico-chemical mechanisms; genetic markers; how the genes control the physical processes. Mathematical modelling in this field seems largely confined to the physical mechanisms of pattern formation; do we have any well-confirmed theories in this area? Do we have so much as a single pair of known Turing morphogens? (John Maynard Smith says we do not, and would almost certainly know.)

Evolutionary issues: Conservation of genes important in development, e.g. hox. Conservation of body plans, and whether this is any more than a statistical artifact (as G. C. Williams argues). To what extent is development constrained, and how much does this effect adaptive evolution? How do developmental programs themselves evolve? The developmental sequence as the thing-which-evolves and selection acts upon (Bonner, and earlier Woodger). Heterochrony. Von Baer's laws (roughly implying: the earlier the stage of development, the more members of two related species resemble each other.)

"Model systems" for developmental biology --- Drosophila, C. elegans, zebra fish, mice, frogs, sea urchins, salamanders, slime molds; what do plant or arthropod developmentalists study? Just how far can we extrapolate from these beasts to the other ~10^8 metazoan species?

See also Adaptation; Biological order; Evolution; Signal Transduction, Gene Regulation and Control of Metabolism