As taught, embryology often seems a lot less dynamic than might be expected. After all, it deals with something going through rapid change. Something recognisably human is formed from a single cell in only a matter of weeks. A lot of embryology is primarily focused on how organs attain their final form. This may be better described as ‘organogenesis’. What of the intermediate or transitional forms that organs take before attaining their final forms? What is going on at a fundamental level?
Embryology can be considered as organismal problem-solving. For example, initially the embryo is formed of a ball of cells—a morula. This reaches a limiting size when it can no longer rely on the passive diffusion of nutrients, respiratory gases and waste products in and out of this simple ball. The cell mass then forms itself into a hollow ball called a blastula. As this enlarges, something different is needed to allow development to continue. Thus, the hollow ball folds in on itself to form a gastrula.
What I have been describing (albeit rather simplistically) is a series of problem-solving steps. At each transition noted above, a problem is being solved. Embryology is not just the formation of an organism as an object; it is the production of a problem-solving entity. The constant problem any embryo needs to solve is how to survive. It does this in different ways at different times depending on what it happens to be like at that time.
