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Waddington called the effect he had seen "genetic assimilation". His explanation was that it was caused by a process he called "canalization".He compared embryonic development to a ball rolling down a slope in what he called an epigenetic landscape, where each point on the landscape is a possible state of the organism (involving many variables).
According to this theory, life span development has multiple trajectories (positive, negative, stable) and causes (biological, psychological, social, and cultural). Individual variation is a hallmark of this theory – not all individuals develop and age at the same rate and in the same manner. [15] Bronfenbrenner's ecological theory
If true, this would challenges the common belief [3] [4] in existence of a fixed maximal human life span. Biodemographic studies have found that even genetically identical laboratory animals kept in constant environment have very different lengths of life, suggesting a crucial role of chance and early-life developmental noise in longevity ...
The Baldwin effect compared to Lamarck's theory of evolution, Darwinian evolution, and Waddington's genetic assimilation. All the theories offer explanations of how organisms respond to a changed environment with adaptive inherited change. In evolutionary biology, the Baldwin effect describes an effect of learned behaviour on evolution.
Assimilation is the process of absorption of vitamins, minerals, and other chemicals from food as part of the nutrition of an organism. In humans, this is always done with a chemical breakdown ( enzymes and acids ) and physical breakdown (oral mastication and stomach churning).
The theory was developed in the 1950s [4] and is used to answer questions about topics such as organism size, age of maturation, number of offspring, life span, and many others. [5] In order to study these topics, life history strategies must be identified, and then models are constructed to study their effects.
The theory is based on the idea that ageing occurs over time due to the damage of the DNA. As an example, studies of mammalian brain and muscle have shown that DNA repair capability is relatively high during early development when cells are dividing mitotically, but declines substantially as cells enter the post-mitotic state. [28] [29] [30]
The theory of recapitulation, also called the biogenetic law or embryological parallelism—often expressed using Ernst Haeckel's phrase "ontogeny recapitulates phylogeny"—is a historical hypothesis that the development of the embryo of an animal, from fertilization to gestation or hatching (), goes through stages resembling or representing successive adult stages in the evolution of the ...