Photograph 51 is the nickname given to an X-ray diffraction image of crystallized DNA taken by Raymond Gosling in May 1952, working as a PhD student under the supervision of Rosalind Franklin, at King's College London in Sir John Randall's group. It was critical evidence in identifying the structure of DNA.
Answer:
b. the bottleneck effect.
Explanation:
The bottleneck effect occurs when a population's size is reduced for at least one generation. This will result in a very reduced genetic variation, which can lead to further adaptation problems.
The Founder effect has its similarities (in terms of the resulting reduced genetic pool) with the bottleneck effect, BUT it occurs when a new colony is started by a few members of the original population.
The Hardy-Weinberg equilibrium is a principle in population genetics that states that the genetic variation in a population will remain constant from one generation to the next IF certain conditions are present (no migration, aleatory mating, among others), so this is not the answer.
Genetic drift (refers to the change in the frequency of an existing gene variant in a population due to random sampling of organisms, so it is not the answer.
Answer: Certain indicators lend clues to this expansion. Wherever we have evidence of family size, families appear to be larger. It does not appear that more babies are being born, but rather that more of them are surviving and people were living longer.
There was no plague or significant famine throughout this period. Generally speaking, this was a period of warm, dry climate through much of Europe, when enormous amounts of new land were brought under cultivation. People did not bring new land under cultivation for no reason. There were mouths to feed and diets improved.
Explanation:
