What are the concepts of random drift, gene flow, and nonrandom mating?

Answer 1

These are evolutionary forces. The special thing about these forces is that they are ALL random, unlike natural selection and sexual selection.

Genetic drift is just the random changes in allele frequencies in a population. Gene flow is the transfer of genes from one popul. to another. Nonrandom mating is directed mating (will affect the allele frequencies of next generation). Nothing too hard to remember...just think about the names.

Answer 2

Random drift - This is the loss or establishment of alleles in a population due to random chance. Essentially, if you have traits which have absolutely no beneficial nor detrimental effects, over time they can disappear or become common simply by random chance. Mid-digital hair on humans is one example. Most humans neither benefit nor suffer from those few little hairs on the middle segment of the finger. Yet, in many human populations, this hair has disappeared, whereas in others, everyone has it. Let's say there are only 10 people in a population, 5 have mid-digtial hair. In the next generation, they have the chance of passing it on, but the frequency in the population may change due to a 50/50 chance of passing on the gene, as well as due to which people in the population happen to reproduce the most. So, the next generation could have only 40% or could have 60% of people with this hair. Eventually, it could get down to one person with or without the hair in the population, and if they fail to pass their trait on...

In classrooms, the way that random drift is generally demonstrated is with jars of beans. You start with 50 white beans and 50 red beans (or you can use M&M's or such) in a single jar. You pick 50 of them out of the jar at random and adjust the proportion in the jars to match this next generation. You keep doing this until one color stops being drawn. Eventually, some students will have only red beans and some will have only white beans. It wasn't because red or white had evolutionary advantages, it was just chance.

Gene flow - This is a pretty generic concept. Basically, this is the introduction of genetic material. Islands are a good example. There are islands which are close enough to each other that birds frequently fly back and forth. There is a lot of gene flow between the birds, because Island A's genes frequently wind up Island B. Rodents may swim across to another island from time to time, so they would have some gene flow too. However, the escaped housecats that live on the islands probably do not have gene flow between their populations because they don't go in the water often. Additionally, there is probably little to no gene flow between that island and one on the other side of the world.

Nonrandom mating - Guppies are a perfect example of this. If you have two ponds of guppies with..green patterns and you introduce one male with a blue pattern into one pond and one male with a green pattern into the other, random mating would say that you would wind up with about the same number of offspring for each male after a given period. However, male guppies with blue patterns are more successful at breeding, because females are more likely to mate with blue males than any other type of male. Mates are not selected at random, they are chosen. This is nonrandom mating.

The guppy example is actually quite an extraordinary one because a particular predator of guppies is able to easily spot blue guppies, so it is an evolutionary disadvantage to be blue, but hey, the females like it, so blue guppies keep being born. In waters free of this predatory fish, you see almost exclusively blue guppies.

Answer 3

what's "gene flow"? what's "non-random mating"? Do the persons who make up new york's Jewish inhabitants decide for his or her friends in a manner it rather is consistent with the assumptions linked with the two or the two a variety of words?

Answer 4

random drift - physical movement

gene flow - biological movement

nonrandom mating - monogamy movement

All three are NATURAL and specific to nature on earth.

Answer 5

That's the formula for making a Liberal