Changes in the heritable attributes of populations of organisms over time. Major mechanisms include drift, natural selection, mutation, and gene flow (migration).

learn more… | top users | synonyms

1
vote
1answer
33 views

Distribution of fitness in wild populations

If I get out in the wild observe wild populations and measure the distribution of fitness $f(w)$ in a given population. What will I find out? Will I observe a Gaussian distribution, a Poisson ...
1
vote
0answers
30 views

Definition of Sexual Selection?

How do you define Sexual Selection (SS)? (One might want to subdivide SS into intra- and inter- SS to answer) Is SS clearly different from Natural Selection (NS)? Is SS nested within NS or are NS ...
0
votes
0answers
25 views

What is a sex-biased gene?

How do you define a male-biased gene and a female-biased gene as they are found in the abstract of this article.
15
votes
3answers
3k views

Were there any flying dinosaurs?

I've seen some articles which came in contradiction with each other. The first article was talking about flying dinosaurs, dinosaurs with feathers and so on. A couple of other articles are talking ...
1
vote
1answer
33 views

What is the evolutionary reason behind human preference for salty foods?

It's been established that food palatability is related to it's caloric density. This hypothesis is used to explain why humans are partial to sugar and fat. But it is also said that humans are partial ...
1
vote
1answer
39 views

What is the difference between these terms: clade, monophyletic group and taxon?

Wikipedia definitions for these terms are pretty similar: http://en.wikipedia.org/wiki/Clade http://en.wikipedia.org/wiki/Monophyletic_group http://en.wikipedia.org/wiki/Taxon They sound like the ...
2
votes
1answer
76 views

What is the evolutionary cause for various finger lengths?

Why are the lengths the way they are with middle finger the longest?
6
votes
1answer
68 views

Evolution of Chromosome Numbers

Some species have different numbers of chromosomes, as we all know. Throughout evolution, how was a species able to survive with an extra chromosome? How was this organism able to breed successfully ...
1
vote
0answers
53 views

Can animals distinguish other animals?

Are animals able to tell the difference between other animals. I dont mean like a cat seeing a dog and thinking "Oh no its a dog". I mean how does prey distinguish predator or threat? Say for instance ...
3
votes
3answers
5k views

Evolutionarily speaking, why do humans have 46 chromosomes

In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Monkeys, chimpanzees, and Apes have 24 pairs (twenty-four pairs), for a total of 48. What caused humans to have 46? ...
1
vote
1answer
39 views

Various Genetic Loads and their Definitions

In population genetics, we talk about several types of genetic loads (also called just loads). I am asking for a exhaustive list and a short definition. Here are for example some genetic loads that ...
7
votes
3answers
648 views

What is the difference between a circular and a cat's-eye pupil?

I've been to local zoo the other day and one lizard caught my attention: its pupils are circular, which, I thought, is not usual for reptiles. Turns out it is, but now I can't find any explanation on ...
0
votes
1answer
33 views

Two-fold cost of sex and r/K selection theory

This article cites a bunch of articles (I haven't been through them) that the effect of the two-fold cost of sex is "reduced" in stable environment or in K-selected environment. It says: [..] the ...
0
votes
0answers
35 views

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 $A_{i1}$ and $A_{i2}$ is only ...
1
vote
3answers
109 views

Why do our eyes close when we sleep?

Why do our eyes close when we sleep? Is it to relax our eye muscles? How can it be explained from an evolutionary point of view?
3
votes
2answers
54 views

Is there an evolutionary explanation for the black spots around a pandas eyes?

I couldn't seem to find one elsewhere, at least not with a scientific source. It would seem as it's quite a striking feature there would be an advantage it would infer.
2
votes
1answer
80 views

“selective pressure” or “selection pressure”?

Editing a manuscript of mine, a co-author changes "selection pressure" to "selective pressure". Are those two terms interchangeable? Or are there subtle differences that I'm not aware of? The ...
1
vote
0answers
29 views

Study case of the inheritance system of Oenothera

I've been told some interesting facts about oenothera. Apparently in this species some lineages have been through some translocations and in results to these translocations and in consequence, some ...
0
votes
0answers
26 views

How important is the womb's environment?

Background Talking about one particular phenotypic trait, the total phenotypic variance $V_p$ is decomposed into genetic and environmental variance for this trait, represented by the symbols $V_G$ ...
15
votes
3answers
28k views

What is the difference between orthologs, paralogs and homologs?

These three terms are often misused in the literature. Many researchers seem to treat them as synonyms. So, what is the definition of each of these terms and how do they differ from one another?
1
vote
0answers
20 views

Series of exercices on population structure (population genetics)

I am seeking for a series of exercices (with solutions if possible) concerning population structure. I am particularly interested in exercices that involve indices such as $F_{ST}$, $F_{IT}$, ...
4
votes
1answer
152 views

Evolution and the levels of selection

Reading Okasha's "Evolution and the levels of selection" he talks about "the levels of selection problem." There is a bit of a problem with this opening chapter because, while he talks about why the ...
17
votes
4answers
2k views

Why are there exactly four nucleobases in DNA?

Does someone know why DNA is composed of four nucleobases? In particular, is there an explanation for the number? Why four and not two, or eight?
3
votes
3answers
117 views

Has it been enough time for evolution through simple natural selection?

Let first state that I understand natural selection. I am not asking if evolution happened. I see evolution as a fact, but I do not assume the current theory of natural selection as fact. I wonder if ...
1
vote
0answers
49 views

Is there an evolutionary explanation for depression?

Evolutionarily speaking, depression (both clinical depression and temporary sadness) is a curious phenomenon. Since being depressed is likely to increase the chance of a person with it to commit ...
11
votes
3answers
692 views

What evolutionary explanations are there for death?

I know death and cancer doesn't hurt humans' reproductive success. It's not helping either. Why do we die? Why dying humans (all of us) are common? What's the point of dying?
0
votes
1answer
52 views

How does Oedipus complex fit in the evolutionary theory? [closed]

This is somthing that really makes me curious. How is posible that trough a evolution process the best posible candidate is the one that falls in love whith his progenitor?
1
vote
1answer
70 views

Coalescent theory - independence of coalescent times

Let $T_i$ be the time to coalesce from $n(t)=i+1$ to $n(t)=i$, where $n(t)$ is the number of sites that have not coalesced yet. In the below example the maximum $n(0)=6$. As I understand it, many ...
5
votes
2answers
219 views

Correlation between genome size and mutation rate?

Martin Nowak in his book "Evolutionary Dynamics" talks about a given correlation between genome size and mutation rate. What correlation does exactly exist between these two concepts? Is it a ...
-4
votes
2answers
101 views

If not intelligent design, what is an alternative scientific theory to evolution? [closed]

In the popular culture, Intelligent Design is often portrayed as trying to be an alternate theory to evolution. However, as the following question points out, it is not scientific, and so cannot be ...
18
votes
7answers
4k views

Why does evolution not make our life longer?

Why does evolution not make life longer for humans or any other species?
-1
votes
4answers
168 views

Does evolution take place universally?

Why does evolution (namely the evolution of primates into humans) take place both uniformly and universally on the earth? Why aren't there any creatures who have not taken the same evolutionary steps ...
2
votes
1answer
52 views

Coefficient of relationship and path of coefficient

A path of coefficient of relationship is defined as $$\rho_{AO} = \left( \frac{1}{2}\right)^n \sqrt { \frac{1+f_A}{1+f_O}}$$ This SE post discusses this definition From this, the coefficient of ...
0
votes
0answers
22 views

Inbreeding Coefficient and Coefficient of Relationship

Wikipedia gives the following formula to calculate a "path of coefficient of relationship" between an ancestor $A$ and an offspring $O$: $$\rho_{AO} = 2^{-n} \left( \frac{1+f_A}{1+f_O} \right)^{1/2} ...
3
votes
0answers
55 views

Selection on linked loci in a diploid population

Let’s consider two linked loci $A$ and $B$ that are both bi-allelic. In consequence, we have four different possible haplotypes $A_1B_1$, $A_1B_2$, $A_2B_1$, $A_2B_2$, which frequencies are $X_1$, ...
8
votes
2answers
137 views

Why is venom more common in fish and snakes than other vertebrates?

Reading this question, I wondered why is it that we associate vertebrate venoms so often with snakes and fish, and more rarely with lizards, amphibians, mammals, and birds (apparently never, in ...
0
votes
1answer
34 views

evolution and mutation of microrganisms against medicines?

I presume microorganisms would have very short life span and they would multiply more creating millions of their kind. Is it really a threat to consider when we use anibiotics and other stuff more ...
5
votes
2answers
61 views

Viruses: Adaptation to a new host through repeated host jumps

A friend told me, during a 3 minute discussion, that viruses that are endemic in host $A$ and make repeated jumps to host $B$ but can't be transmitted between individuals of species $B$, may slowly ...
0
votes
0answers
28 views

Book Recommendation: Complex Traits and Complex Genetic Architecture

I am looking for a book (or any good source of information) that offers an in-depth discussion and models about the evolution and analysis of complex traits and complex genetic architecture. Do you ...
0
votes
1answer
41 views

Defining: Evolutionary (quantitative) Genetics and Population Genetics

How do we define the fields that are Evolutionary (quantitative) genetics and population genetics. What set these two fields apart? Can you try to provide definitions? To my intuitive understanding, ...
6
votes
2answers
199 views

How Sex Evolved ? and when?

As I know evolution comes bit by bit mutation by mutation How sex evolved which requires a major change in at least two individuals one to become male and one to become female ? When that happened ...
0
votes
0answers
28 views

How would a different solar day affect evolution?

Has anyone theorized how evolution would be affected by a different length of solar day, what were the conclusions? The thought came from thinking about life on other planets/moons, but I'm initially ...
3
votes
2answers
234 views

How are two species with similar phenotypes identified as different?

How are two species with similar phenotypes identified as different? Have two different individuals that were thought to be different species ever been determined to be from the same species ( or ...
1
vote
2answers
105 views

Which was the last significant event in human evolution? What's next?

At 10.000 BC (12 ka), we became the last of the Homo species on Earth. In evolutionary terms this is a very little time range to something happen, but I'm wondering anyway, in this meantime which are ...
0
votes
0answers
33 views

Effects of Genetic Drift on Linkage Disequilibrium

From what I understood of @Canadianer's answer here... Genetic drift randomly causes negative or positive linkage disequilibria, by changing allele frequencies through random sampling. Natural ...
2
votes
3answers
84 views

Many spermatozoa, but just one ovum

Why do men produce so much spermatozoa, that will get discarded, but women, just ovulum, but it's a good one. Couldn't men produce good spermatozoa as a limited edition? Where is the evolutionary ...
2
votes
1answer
118 views

Why do genetic drift generates negative linkage disequilibrium?

The very first sentence of the abstract of this article are: "In finite populations subject to selection, genetic drift generates negative linkage disequilibrium, on average, even if selection ...
1
vote
1answer
124 views

Heterozygosity and overdominance

Consider $m$ loci with heterozygote advantage (overdominance) such that the fitness of the two homozygotes is $1-\frac{s}{2}$ and the fitness of the heterozygotes is $1+\frac{s}{2}$, where $s>0$. ...
3
votes
1answer
89 views

Are people genetically predisposed to being interested in specific fields/ideas? How does specialization occur?

I'm not sure if I formulated my question well, but I'm curious about a couple statements made by Steven Pinker and and James Heckman. In this interview: ...
1
vote
1answer
39 views

definition of tempo and mode in evolution

I am reading Punctuated Equilibria: The Tempo and Mode of Evolution Reconsidered, which mentions the "tempo" and "mode" of evolution. I'm not familiar with the related literature and when I google the ...