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1

There was a paper that attempted to assess this published in 2010 There’s plenty of time for evolution - Herbert S. Wilf and Warren J. Ewens There is also a layman's explanation of this here Basically when we account for the fact that genes evolve in parallel under a number of simultaneous trials, it appears that there is indeed enough time for species to ...


1

I think there is some misunderstanding there, natural selection does act on an individual and can be determined by its genes (assuming there is genetic variance underlying the variance in trait). Those with more favourable genes will have more favourable phenotypes and thus be more likely to survive/reproduce. However, (genetic) evolution does not occur ...


2

I think you have misunderstood the passage. Here is a larger section (found at google books): Natural selection can also occur at the level of species, for certain characteristics enhance the rate of origin of new species or diminish the likelihood of species extinction. For instance, the number of species in lineages of herbivorous insects has generally ...


0

LD describes the associations among alleles at different loci. For anything more than two bi-allelic loci, you need more than just one number to fully describe the associations. For instance, if we have three bi-allelic loci 1-3, we need the three pairwise LD coefficients, plus one extra three-way coefficient. In general, if we have $K$ loci, and the ...


1

Being a typical molecular biologist, I am a little uncomfortable with classical genetics terms. I might redefine some symbols (perhaps to mean the same) [It is like talking to oneself while thinking]. There are four DNA-blocks : A1, B1, A2 and B2. Ak and Bk are adjacent blocks. [Perhaps this is same as what you defined the symbols as]. A and B are ...


5

Drift is a random element of evolution from one generation to the next, it is equally likely to spread a deleterious mutation as a beneficial one. The reason the answer is D is because selection should remove a deleterious allele, while drift makes no distinction, and is therefore the only scenario where drift is expected to be a reasonable answer. However, ...


2

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. ...


1

The honest answer to this and many other similar evolutionary questions is that we don't know the answer. We can sample information from many different points along an organism's developmental timeline using the fossil record, genetics, etc. and reconstruct various states of said organism's development. The overwhelming evidence is that evolution is the ...


3

Organisms on Earth did not evolve in a homogenous environment. A critical part of speciation (when you go from a single species into two or more) is a reproductive barrier. This can be a literal, physical barrier - mountain range appears between two populations, valley in the middle of habitat floods and isolates the two halves of the population, a small ...



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