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13

Let's see! I took the most recent WHO data from here and did a quick an dirty analysis in R. Here is the histogram as well as a normal distribution with the same mean and standard deviation as the actual data: Does not look very normally distributed. In fact, the shapiro test confirms this impression: Shapiro-Wilk normality test data: df$...


9

You can access the Imperial College global population dynamics database. They will have time series data at specific locations. http://www3.imperial.ac.uk/cpb/databases/gpdd There is a sister database as well that might be useful. http://lits.bio.ic.ac.uk:8080/litsproject/ These contain several hundred time series, and you can see a paper that used them ...


9

Are you looking for 'Home range' (see also the definition in Encyclopaedia Britannica)? Generally, 'home range' is defined as the entire area an individual animal uses, while the 'territory' is the subset of the home range that is actually defended from conspecifics (in animals that show territoriality). 'Home range' is often delimited by the types of ...


8

You can use power analysis to work out answers depending on the specifics of your data. The things you need to consider are: The power of the test. This is the probability that the test will fail to reject the null hypothesis even if in truth it is false (Type II error). If the population is not in equilibrium, what is the probability that the test will ...


8

I think it does make sense - with a population density for finland that is so low, the disease with such a low beta cannot communicate to enough people to propagate. The number of people who have this disease will be fewer each week. I think this makes sense because at 16 / km^2, you can expect that practically nobody will ever see each other. This is ...


7

1 billion hives (at 10,000-50,000 bees/hive this is 10-50 trillion bees) Managed: 100 million hives Based on country-level data from FAO, supplemented for a few countries with Apiservices, in 2011 there were about 80 million managed hives. Because FAO lacks any data for some countries, and other countries under-report (for instance US figures don't ...


6

Here is my full derivation to the book example you gave, hopefully it'll help you clear up what went wrong: You need to remember that after there is selection acting on the population, you no longer have a total of 1 after selection. Think of selection as "killing" individuals, which means the total is now 1 minus what has been "selected out". s*y is what ...


6

To me, there are two issues that are mixed up here (if I understand you correctly). First, do you want to estimate the mean and variance for a statistical population (i.e. to characterize a larger population by independent samples), or do you want to calculate the actual density for a particular area, where you have counted all occurences in that entire area ...


5

Well, I think I found the very simple mistake I madeā€¦ Looking again in my equations, I realize that (for some reason) $cor = 2 \cdot \frac{\sigma_A^2}{\sigma}$ And looking at this website, I see that the slope of the parent-offspring regression is $\frac{h_N^2}{2} = slope$ Here was my mistake!


5

Your calculations are the following. Assuming non-overlapping generations, the number of ancestors you have in the last $t$ generation is given by: $$\sum_{i=1}^t 2^t$$ This sounds correct. But there are some very strong assumptions: Generations are non-overlapping. A more realistic model would need to consider $t$ as a continuous variable a give a ...


5

I guess you meant the population size stability. It is considered that the biosystems will increase their capacity of adaptation when evolving in very fluctuating environments. I believe the population stability is embedded in the adaptability of individuals. There is a measurement about it, evolvability, when the environment changes, the faster the ...


5

To avoid confusion I just want to add to fileunderwater's answer the equivalent words we use to describe the "area size a population/species lives in". The spatial range a single individual occupies is generally called home range or territory (as fileunderwater said before me). The spatial range a single species (or population) occupies is called ...


4

It is certainly possible as yes, rapid population growth will reduce LD. From Slatkin, 1994: In a rapidly growing population, however, there will be little chance of finding significant nonrandom associations even between completely linked loci if the growth has been sufficiently rapid. Or Nature Reviews, 2002 Przeworski... showed that population ...


4

There are a number of things to clarify here; Fecundity is the number of offspring that is produced by an individual, and this can be separated into potential fecundity (maximum reproductive capacity) and realized fecundity (number of offspring actually produced). Realized fecundity is very similar to fertility, which is defined as the number of viable ...


4

Mendel published his results 1866 but they were rediscovered only in 1900. The Hardy-Weinberg model is an application of Mendel's rules to a population that is not under selection forces. So the one builds on the other, and Hardy-Weinberg is a simplification model-wise, and Mendel's rules are not detailed enough either. It's the same relation as with a ...


4

After talking to my teacher, he said that biological control is the introduction of species to control another species, however species may be introduced for other reasons (the "Introduced Species" method), such as to "assist an ecosystem cope, flourish or re-establish itself." The example he gave was the introduction of South African veldt grass to ...


4

An easy way to visualize the mistake in your thought experiment is to consider a bottleneck event, when the ancestral population was very small, maybe just a few individuals. This would mean that the entire current population is descending from just a few individuals. Your thought experiment is assuming that the "pyramid" of your ancentors is expanding all ...


4

According to Hartl & Clark on population genetics: "Population genetics deals with Mendel's laws and other genetic principles as they apply to entire populations of organisms.... also includes the study of the various forces that result in evolutionary changes in species through time." According to Conner & Hartl also on population ...


4

Recap of the question: Looking at a single locus trait ($A$) controlled by two alleles, $A_1$ and $A_2$, the phenotypic mean is only affected by inbreeding depression, $f$ (Wright's inbreeding coefficient), if there is some degree of dominance, $d$. Why? Answer: If we take inbreeding as a higher than expected frequency of homozygotes, such that if the ...


4

Could not fit in a comment.... To make sure we all understand your question... Is your question how many (eukaryote) species are currently living? or How many (eukaryote) cells are currently living?? Just a hint to answer the question Micheal Lynch, in his book (On the Origin of Genome Architecture) at page 3, Box 1.1 tries to answer the question How ...


4

Note: This is not an area where I know the litterature well Where are many counteracting processes to consider for this question. For instance, the rate of evolution will be affected by the rate of mutation, the distribution of positive and deleterious mutations, strength of selection, whether the fitness effects are small or large, if fitness effects ...


4

First of all, the $\mu$ is not expected time for a mutation to occur and get fixed; it is the rate at which mutations are fixed in the population. The basic result states that if neutral mutations arise at a locus at rate $\mu$ within individuals, mutations at this locus will be fixed in the population at rate $\mu$ as well. The expected time for a given ...


4

The reason that an unequal sex ratio affects the effective population size is because offspring are produced by one male and one female parent, and an unequal sex ratio increases the rate at which genetic drift will occur. "...the smaller number of males still contributes half of the genes in the next generation..." In words, assuming the male ...


4

Considering your assumption: I'm just looking at the exponential part, where the simple exponential equation works. If we assume there's sufficient nutrients for bacteria to grow unchecked for a number of hours (more-or-less true in a real culture) In your original model you are using discrete states and fixed time steps. So, if 30 min is one ...


3

I don't believe you can produce a general function for this. It will depend on the exact gene and organism you are considering. From a molecular point of view, the vast majority of recessive mutations result from a change producing either a non-functional protein product or a truncated product that is cleaned up by the cell. We can reasonably assume that ...


3

To a good first approximation $\overline{\Delta f} = 0$. Where $\overline{\Delta f}$ is the mean change in fitness down to any point or indel mutation. The reasons for this are as follows: In the genome of higher organisms, most of the genome is non-functional ("junk") so most mutations will not have any effect regardless of the change made. A substantial ...


3

I'll kick this off with an attempt at a definition: a selection regime is the set of selective pressures on a population As in, "alteration of selection regime resulting from harvest" (Mooney & McGraw 2007) or "Human-induced nutrient input can change the selection regime and lead to the loss of biodiversity. For example, eutrophication caused ...


3

Biological control does not have to be with an introduced species. It can also be accomplished by either artificially inflating the number of existing predators. E.g. Spruce bud worm has a natural predator in the form of a tiny wasp. But budworm can spread through a stand faster than the wasp can. By moving popluatins of the wasp to the forefront of the ...


3

There are so many things that are implied in this paper, not explicitly said. The mutation rate here detected seems to be the emergence of chain-terminating (CT) mutations, which truncate protein coding genes, usually just one gene in a bacterium or phage, which would be possible to observe from inspecting a plate to see which colonies die or survive. ...


3

A Poisson process follows these postulates: $\lim\limits_{h\to0+}\frac{P(N_h=1)}h=\lambda$ i.e. the probability of occurrence one event in a very small interval of time is equal to the macroscopic rate or intensity ($\lambda\,$). $P(N_h\geqslant2)=o(h)$ i.e. the probability of occurrence of more than one events in an infinitesimal interval is essentially ...



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