Abstract: Embryonic development, which inspired the first theories of biological form, was eventually excluded from the conceptual framework of the Modern Synthesis as irrelevant. A major question during the last decades has centred on understanding whether new advances in developmental biology are compatible with the standard view r whether they compel a new theory. Here, I argue that the answer to this question depends on which concept of morphogenesis is held. Morphogenesis can be conceived as (1) a chemically driven or (2) a mechanically driven process. According to the first option, genetic regulatory networks drive morphogenesis. According to the second, morphogenesis results from an invariant tendency of embryonic tissues to restore changes in mechanical stress. While chemically driven morphogenesis allows an extension of the standard view, mechanically driven morphogenesis would deeply transform it. Which of these hypotheses has wider explanatory power is unknown. At present, the problem of biological form remains unsolved.
– Linde-Medina, M. On the problem of biological form. Theory Biosci. 139, 299–308 (2020). (paywall) https://doi.org/10.1007/s12064-020-00317-3
Shouldn’t it have been a wakeup call that embryonic form was excluded from the Modern Synthesis (= neo-Darwinism) as “irrelevant”? Raised too many questions?
“invariant tendency to restore changes in mechanical stress”.
Isn’t that pretty much Hooke’s Law? You’d think a theory that purports to explain the forms of life would at least try to explain the VARIED forms of life, instead of explaining the form of a rubber ball.
Wasn’t there a cartoonish video on this subject, showing all living things as spheres?
And yet people are still being taught that phenotype (ie form) = genome plus environmental factors. They should teach that we don’t know what determines form so someone can go and try to figure it out.