Cortical inheritance


Cortical inheritance

Cortical Inheritance or structural inheritance was discovered by Tracy Sonneborn, and other researchers, during his study on protozoa in the late 1930s. Sonneborn demonstrated during his research on Paramecium that the structure of the cortex was not dependent on genes, or the liquid cytoplasm, but in the cortical structure of the surface of the ciliates. Preexisting cell surface structures provided a template that was passed on for many generations.[1]

John R. Preer, Jr., following up on Sonneborn's work, says, "The arrangement of surface structures is inherited, but how is not known, Macronuclei pass on many of their characteristics to new macronuclei, by an unknown and mysterious mechanism."[2]

Other researchers have come to the conclusion that "the phenomena of cortical inheritance (and related nongenic, epigenetic processes) remind us that the fundamental reproductive unit of life is not a nucleic acid molecule, but the remarkably versatile, intact, living cell."[3]

An article in Newsweek mentions research that shows that "Some water fleas sport a spiny helmet that deters predators; others, with identical DNA sequences, have bare heads. What differs between the two is not their genes but their mothers' experiences. If mom had a run-in with predators, her offspring have helmets, an effect one wag called "bite the mother, fight the daughter." If mom lived her life unthreatened, her offspring have no helmets. Same DNA, different traits. Somehow, the experience of the mother, not only her DNA sequences, has been transmitted to her offspring."[4]

See also

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External links


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