Ad
related to: what does generation mean in biology math examples for class
Search results
Results From The WOW.Com Content Network
Say that the natural number t is the index the generation (t=0 for the first generation, t=1 for the second generation, etc.). The letter t is used because the index of a generation is time. Say N t denotes, at generation t, the number of individuals of the population that will reproduce, i.e. the population size at generation t.
One may then define the generation time as the time it takes for the population to increase by a factor of . For example, in microbiology , a population of cells undergoing exponential growth by mitosis replaces each cell by two daughter cells, so that R 0 = 2 {\displaystyle \textstyle R_{0}=2} and T {\displaystyle T} is the population doubling ...
Coalescent theory is a model of how alleles sampled from a population may have originated from a common ancestor.In the simplest case, coalescent theory assumes no recombination, no natural selection, and no gene flow or population structure, meaning that each variant is equally likely to have been passed from one generation to the next.
When generation overlapping is incorporated in this model, the substitution rate does change with population size fluctuations. The substitution rate increases when the population size transits from small to large, with a high survival probability and when the population size transits from large to small, with a low survival probability.
A little mathematics of the multiplication-table type is enough to show that in the next generation the numbers will be as (p + q) 2:2(p + q)(q + r):(q + r) 2, or as p 1:2q 1:r 1, say. The interesting question is: in what circumstances will this distribution be the same as that in the generation before?
This generation is known for being digital natives, even more so than Gen Z, having been born into a world that is fully integrated with technology, social media and global connection.
Example for a trait under positive selection. The Price equation shows that a change in the average amount of a trait in a population from one generation to the next is determined by the covariance between the amounts of the trait for subpopulation and the fitnesses of the subpopulations, together with the expected change in the amount of the trait value due to fitness, namely ():
Income. The range of incomes needed to be middle class follows a pattern that is to be expected. It begins low for younger generations, increasing until Gen X, at which point it begins to decline.