Topic genetics / heredity

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Topic genetics / heredity (part 1/2)

telegram translate:

Is heredity necessarily tied to DNA?
The experiment with the umbrella alga showed that this is not the case, as did the following excerpts:

  • Spiegel (2014):

"Greetings from ex - A mother's previous sex partners influence the appearance of later offspring - researchers have shown this in flies."

  • Researchgate (2014):'s_previous_mate

"Newly discovered non-genetic mechanisms break the link between genes and inheritance, thereby also raising the possibility that previous mating partners could influence traits in offspring sired by subsequent males that mate with the same female ('telegony'). In the fly Telostylinus angusticollis , males transmit their environmentally acquired condition via paternal effects on offspring body size.We manipulated male condition, and mated females to two males in high or low condition in a fully crossed design.Although the second male sired a large majority of offspring, offspring body size was influenced by the condition of the first male."


 Topic genetics / heredity (part 2/2)

In 1820 Lord Morton had mated a chestnut Arabian mare with a quagga zebra stallion, and this was also reflected in the descendants of the generation after that (although the mare was again mated with an ordinary stallion).

This is the phenomenon of telegony, which states "that a previous pregnancy in both humans and animals can affect the phenotype of offspring from subsequent pregnancies." 
( German)'s_mare


The Surgeon-General of New York, the physiologist Austin Flint, in his Text-Book of Human Physiology (fourth edition, 1888) described the phenomenon as follows:[10]

A peculiar and, it seems to me, an inexplicable fact is, that previous pregnancies have an influence upon offspring. This is well known to breeders of animals. If pure-blooded mares or bitches have been once covered by an inferior male, in subsequent fecondations the young are likely to partake of the character of the first male, even if they be afterwards bred with males of unimpeachable pedigree. What the mechanism of the influence of the first conception is, it is impossible to say; but the fact is incontestable. The same influence is observed in the human subject. A woman may have, by a second husband, children who resemble a former husband, and this is particularly well marked in certain instances by the colour of the hair and eyes.