Magic embryology: rules for growing a new fetus (Introduction)

by David Turell , Friday, January 24, 2020, 20:39 (1765 days ago) @ dhw

QUOTE: The homologous morphological resemblance among the phyla may, in fact, be due as much to the inevitable topological trajectory of the confined expansion of a primordial spherical membrane as it is to common ancestry.

DAVID: Homologies are similar formations in structure and for common descent he assumes the lookalikes are all set up by the same physical shaping forces all through time.

dhw: Thank you, but I understand “homologies” – it’s the “topogical trajectory” etc. that I don’t understand. But we agree about chance and common descent, so let’s leave it at that.

DAVID: Sorry about that. 'Topological trajectories' means shaping forms of organs and bodies from forces in tissues already in prior existence resulting in forcing more directional cell growth.

dhw: Thank you. Topology = the anatomy of any specific bodily area, structure or part. So if I may put this in plain English, they are saying that the similar formations are due to the fact that changes take place in existing structures though these remain basically the same. In that case, the similarities are not “due” partly to common descent; the similarities are the evidence for common descent!

The forces have to act on what exists in the very early embryo, which generally reflects the past shapes, result, the appearance of common descent as part of the process. We agree.