ici, je discute simplement.
les forums ne sont rien d'autre que des remarques, et en aucune façon des puits de science où prendre de bonnes leçons.
pour apprendre, il y a beaucoup mieux, naturellement.
je profite de cette caractéristique des foras pour dire que Mendel, Darwin et surtout, Lamarck, ne sont pas du tout "out" puisque régulièrement ils reviennent à la surface à la suite de découvertes issues d'expérience menées autour du globe.
Finally, there is growing evidence that cells can activate low-fidelity DNA polymerases in times of stress to induce mutations. While this does not directly confer advantage to the organism on the organismal level, it makes sense at the gene-evolution level. While the acquisition of new genetic traits is random, and selection remains Darwinian, the active process of identifying the necessity to mutate is considered to be Lamarckian.
In 1988, John Cairns at the Radcliffe Infirmary in Oxford, England, and a group of other scientists renewed the Lamarckian controversy (which at that point had been a dead debate for many years). The group took a mutated strain of E. coli that was unable to consume the sugar lactose and placed it in an environment where lactose was the only food source. They observed over time that mutations occurred within the colony at a rate that suggested the bacteria were overcoming their handicap by altering their own genes.
The inheritance of acquired characteristics
Recently, researchers have reexamined this concept in light of discoveries in epigenetics and transgenerational epigenetics. In some cases, experiences of parents or even grandparents have been found to cause differences in gene expressions.
finalement, sans rien y connaître, je réfléchis pas trop mal
on peut en déduire que le simple examen de l'ADN ne suffit pas pour expliquer l'évolution , non ?
