Summary

Endless Forms Most Beautiful

the New Science of Evo Devo and the Making of the Animal Kingdom
A great introduction and review of the work linking the developmental impact of reusing the master regulatory proteins to control a changing galaxy of specific proteins to alter the final organisms form to fit its habitat. He details the emergence of the body axes under the Hox proteins and how they work to isolate the expression of genes to promote modularity. Isolation makes regional use of bone, collagen, epithelium etc independent of other modules that also use the same genes. This allows constant tinkering without pleiotropic disruption. The final result is: 1 Hox mapping regulation proteins. Body axis planers. 2 Master body specializing regulators. Eye, limb bud, heart. Look up Pax6, Dll, Tinman for examples of DNA binding regulatory proteins. 3 Regulators at the cell level to keep the life process going. Cellular housekeeping genes 1 - reuse what is already there – modify preexisting systems. 2 – multifunctionality & redundancy. If the systems do overlapping jobs there is space to separate and specialize. Division of labor => niche adaptation 3 – modularity to allow modification of isolated regions independent of other modules that also use the same genes. Modular architecture - Isolate the control to the geographic position. Master genes for mapping and local master organizers- expressed homeobox proteins The physical geography Complex DNA regulatory patterns to provide regulatory combinations of switch settings. Allows reuse in time and specify cell type expression.