Questions tagged [population-biology]
Questions pertaining to populations of organisms.
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Drake's Law. What is the genome-wide mutation rate and what are the estimates?
Drake's rule
Drake's rule states that the genome-wide mutation rate is more or less constant across all species — from E.coli to the house sparrow.
Data
From what I think being Drake's original ...
8
votes
1
answer
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Effect of sex-ratio on the effective population size
As stated on this wikipedia article, the effective population size $N_e$ when the sex ratio differs from $\frac{1}{2}$ is
$$N_e = \frac{4N_mN_f}{N_m+N_f}$$
I understand the biased sex-ratio ...
6
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1
answer
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Variance in Fst in the infinite island model
The most famous result in the study of structured populations come from Sewall Wright. He showed that in an island model, where each subpopulation is of size $N$ and the migration rate is $m$, then ...
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Why does the number of mutations per individuals follow a Poisson distribution?
I was reading this review. On page 11, left column, first paragraph, one can read:
[..] there is a Poisson distribution of the equilibrium number of mutations per individual, if fitness effects are ...
2
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1
answer
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Additive genetic variance with $n$ alleles
The genetic variance of a quantitative trait (the quantitative trait in question is fitness) can be express as the sum of two components, the dominance and additive variance:
$$\sigma_D^2 + \sigma_A^...
2
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1
answer
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Additive genetic variance with $n$ loci
The genetic variance of a quantitative trait (the quantitative trait in question is fitness) can be express as the sum of two components, the dominance and additive variance:
$$\sigma_D^2 + \sigma_A^...
11
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2
answers
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Is global life expectancy normally distributed?
I am trying to find out what the world distribution of life expectancy looks like.
8
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1
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How many eukaryotes are there on Earth?
I have been reading:
William B. Whitman, David C. Coleman, and William J. Wiebe, "Prokaryotes: The unseen majority", Proc. Natl. Acad. Sci. USA 95, pp. 6578–6583, June 1998. [Full Text] [PDF]
...
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How is (Insect) population control through male sterilization effective
This is no doubt a simple question.
I was reading about Sterile Insect Technique where sterile males out-compete non-sterile ones to mate with females and thus reduce the population.
My question ...
7
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2
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Within and Between Allelic Class Diversity
I am reading Charlesworth et al. 1997. They talk about diversity within and between allelic classes.
Nucleotide diversities ($π$) at each neutral site were estimated from the mean of $2 \sum z_t (1-...
6
votes
1
answer
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Viruses in human history
How much do we know about ancient viruses and the viral evolution throughout the human history?
To my knowledge the HIV history has been rather well documented for about hundred years back (e.g., see ...
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History: Do evolutionary and ecological processes occur at the same timescales?
Classically, it was thought that evolutionary processes occurred at a much slower pace than demographic/ecological processes. Nobody, ever thought about incorporating both processes into the same ...
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1
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How do I calculate the change in allele frequency in a haploid population under selection?
From this book
For simplicity, let us consider a haploid organism and assume that the frequencies of alleles $A_1$ and $A_2$ are given by $x$ and $y=1-x$, respectively. We also assume that the ...
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3
answers
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Initial population when I count backwards?
My question deals with the number of ancestors it took to produce me:
--> To produce me, it took 2 people (my parents) = ($2^1$) people = 2
--> One generation further included = ($2^1 + 2^2$) ...
4
votes
1
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How could one calculate the gene flow between two populations?
Imagine there are two populations X and Y, and for each population you have the genotypes of each individual in that population (e.g. Aa, AA, aa, etc.), but for multiple loci (e.g. AABb).
How could ...
4
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1
answer
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How to calculate the effective population size ($N_e$) with overlapping generations?
From this Source: If generations are overlapping, then the effective population size $N_e$ does not equal the population size $N$.
I know mathematical formulations in order to find the effective ...
4
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$F_{ST}$ and the genetic variance in metapopulations
From this video (21'15''), the speaker gives the following formulae in order to calculate the between and among populations genetic variance from the $F_{ST}$:
$$V_{Among Pop} = 2 F_{ST}V_G$$
$$V_{...
4
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1
answer
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Book recommendation on selective breeding?
I am looking for a good book that gives a nice overview of the science and technics of selective breeding. I am particularly interested in the use of population genetics to support decision in this ...
4
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1
answer
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Guide to learning about Population biology / ecology / dynamics for a non-Biologist
I'm an applied mathematician who works in the field of feedback control systems but has been becoming interested in looking at population biology (e.g. Lotka-Volterra, Mathusian growth,etc.) from a ...
3
votes
2
answers
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Heterozygosity under genetic drift
The wright-Fisher model of genetic drift is:
$$p_{ij} = \binom{2N}{j}\left(\frac{i}{2N}\right)^j \left(1- \frac{i}{2N}\right)^{2N-j} $$
,where $\binom{2N}{j}$ is a binomial coefficient.
From this ...
3
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1
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How to determine the relationship of competition or cooperation?
I am currently studying the interaction of Twitter memes (two or many), such as competition and cooperation. Is there any model or method in biology that can identify the types of the relationship, ...
3
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1
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Inbreeding depression and dominance
From this article, second paragraph of the second page
A classic theoretical result is that the mean of a character controlled by a single locus i with two alleles Ai1 and Ai2 is only affected by ...
2
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0
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Is a nightly curfew an effective intervention strategy for limiting the spread of an infectious disease? [closed]
The governing bodies of several geographic areas hit by disease outbreaks will sometimes impose a nightly curfew on their citizens, restricting or limiting the ability of their citizens from going ...
1
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1
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Hardy-Weinberg applied to three alleles and stimation of allele frequencies
I have this equation:
Corresponds to HW in equilibria with three alleles:
$(p+q+r)^2=1$
Expanding the square results:
$p^2+2pq+r^2+2pr+q^2+2qr = 1$
I need to separate homozygous and ...
1
vote
1
answer
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Hardy-Weinberg equilibrium generalized to add inbreeding (non-random mating)
Background
Quoting from Gillespie's book
The level of inbreeding is measured by the inbreeding coefficient, $F_I$, which is the probability that two alleles in an individual are identity by ...
1
vote
2
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Effect on fitness of mutations
What is the distribution/probability density function (PDF) of impacts on fitness of new mutations?
I very welcome any partial answer that does not give the whole PDF but just some information about ...
1
vote
1
answer
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Dominance/recessivity of new mutations
What is the distribution/probability density function (PDF) of recessivity/dominance of new mutations?
I very welcome any partial answer that does not give the whole PDF but just some information ...
1
vote
1
answer
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Human population growth - where can I find the data?
Out of curiosity, I'd like play around with data of human global demography.
Where can I find data that describe the "per region (per continent for example) population size" versus time since the "...
0
votes
1
answer
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Accurate surveys of urban pigeon and bird populations
I've been working on an assignment to develop mathematical models of urban pigeon populations. (As a disclaimer, this is part of a math course, not a biology course). I already understand the ...