Questions tagged [natural-selection]

A mechanism of evolution that leads to non-random spread of genes due to the effect that genes have on reproductive success.

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Evolution of the haplo-diplontic life cycle

From wikipedia > Biological Life Cycle: haplontic life cycle - the haploid stage is multicellular and the diploid stage is a single cell, meiosis is "zygotic". diplontic life cycle - the diploid ...
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What problem does the Dobzhansky-Muller Model resolve?

This page describes the Dobzhansky-Muller model and I can follow the illustration of the split leading to incompatible hybrids. But at the start of the page the author states "[Dobzhansky and Muller] ...
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Balancing selection vs introgression?

Balancing selection can maintain polymorphisms in natural populations for extended periods of evolutionary time. However, in this paper, Dannemann et al. 2016 identify three archaic haplotypes in the ...
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Can Females Songbirds Have Male Plumage?

Male birds are colorful for courtship displays, females are dull for camouflage. But, is written in a website somewhere that sometimes, when females birds are sterile, they grow male plumage due to ...
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What is the probability of fixation for a mutant under fluctuating selection?

Here is an answer which explains how one can model the frequency of an allele that is under fluctuating selection (the selection that varies through time). Not, thinking about fluctuating selection, ...
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Exact terminology of natural selection

You don't need to explain to me what the theory of evolution is, or how it works. This question is purely about what exact meaning the word "natural selection" is ascribed to. There seem to be ...
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Why haven't modern grass based crops overrun wild grasses?

Modern grass based crops are significantly superior to wild grasses, they grow faster, are stronger stemmed, have larger leaves and higher seed yields in terms of individual seed size, giving ...
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Increase rate of change in coding regions?

If a sequence is under selection will it acquire more changes over time because of faster fixation than if changes were neutral? Is this true or am I missing something?
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Is the suicide of a moribund individual to be considered group selection?

When a moribund individual commits suicide (e.g., Refardt, Bergmiller & Kummerli, 2013; http://rspb.royalsocietypublishing.org/content/royprsb/280/1759/20123035.full.pdf), is this to be considered ...
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How does better sperm result in more viable offspring?

Quoting wikipedia: Greater choice and variety of mates increases a female's chance to produce more viable offspring. This led me to the question: "How sperm parameters are connected with entity ...
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Why do many people seem to prefer unhealthy compared to healthy foods?

I don't have any concrete statistics on this but many of us seem to love the taste of food that is unhealthy for us. Over the centuries, wouldn't it have been a non negligible advantage to those who ...
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Why are there species instead of a continuum of various animals?

As I understand it, various animal traits have to evolve gradually, but what happens to the species that are "neither here nor there"? To put it differently, if a species evolved from another, it did ...
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What is the definition of “Natural Selection”?

Natural selection is the differential survival and reproduction of individuals due to differences in phenotype. Natural selection, a process that results in the adaptation of an organism to its ...
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What is meant by `individuals do not evolve, populations do`?

My university professor stated that "individuals do not evolve, populations do". But aren't populations made up of individuals? That's like saying when a compound changes in stability, none of the ...
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How does Darwinian Evolution work?

Let me explain... A friend and I read some articles, part of a Biology book, and watched a video on evolution. We then tried to explain what Evolution is to each other. My friend said that Natural ...
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Are Males the main evolutionary tool for production of genetic variation necessary for evolution?

What I'm saying here is just a personal reflection, that might turn to be gravely erroneous, actually I'm asking that because I didn't see it presented elsewhere. Evolution is propelled by two ...
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Is there a biological mechanism for evolution encoded into our DNA?

Throughout high school, I remember learning about Darwin's theory of evolution as if it were near-fact. But something always seemed wrong about the ideas presented. Survival of the fittest Random ...
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How is “selection” best defined?

There is natural selection but there is also sexual selection which some regard as a category of natural selection. There is also artificial selection (by humans). The question is, what is a most ...
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Is this model of understanding of what's natural selection and what's not, correct? [closed]

Here in this account I just want to make sure, that I've grasped the concept of natural selection as is usually spoken by evolutionary biologists, truly the wording here are non standard and in some ...
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Why do some bad traits evolve, and good ones don't?

If a trait would be advantageous to an organism then why hasn't it evolved yet? Conversely, if a trait is not advantageous or mildly disadvantageous, why does it exist? In other words why does ...
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Is Mutation Theory still “valid” for complex organisms?

I'm afraid like most people I suffer from having learned "A History of Evolution" in school, rather than cutting to the chase and learning the actual "up to date" version of the subject. (Imagine if ...
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Are inadvertent environmental catastrophes also examples of natural selection?

I just want to understand the concept of natural selection and its relation to evolution. Evolution by natural selection occurs when we have hereditary trait(s) that causes an effect on reproduction ...
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How does natural selection explain how organisms that are poisonous evolved?

Natural selection makes perfect sense when describing the evolution of say camouflage. For example 2 bugs of the same species live on a tree. One is mutated to look slightly more like a tree, so the ...
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Animal with “advantageous” trait in a environment where the trait is never utilized (high cold tolerance in mild climate) - natural selection occur?

If you were to put an animal with a certain type of seemingly advantageous "trait" into an environment where the trait was not necessarily needed, ex: Putting an animal with a high tolerance for cold ...
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What are the advantages of sexual reproduction over asexual reproduction? [closed]

What are the advantages of sexual reproduction over asexual reproduction? How does variation influence ecological and evolutionary success?
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Does natural selection select for randomness in development?

In a podcast with Sean Carroll and Liv Boeree they discuss a result from game theory that the optimal strategy in the face of incomplete information can require random decision making. For example, ...
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Finding intensity of selection against dominant homozygotes

I was looking at some Olympiad questions and came across the following: If the frequency of a completely recessive allele is $0.2$ and it remains unchanged from generation to generation due to ...
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Ways creatures evolove [closed]

I can't find the right answers to my questions online . are there other ways creatures evolove apart form nsatural selection? Thank you
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You need DNA to make RNA, and RNA to make DNA, so they had to come into existence at the same time?

A statement I recently read: 'Evolution is debunked and gives no basis for morality. Natural Selection throws away info, it does not add. You need DNA to make RNA, and RNA to make DNA, so they had to ...
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Does consistency in minor allele frequency of a SNP across populations imply selection?

If a particular SNP has very similar MAF value across multiple largely non-overlapping populations, with the assumption of no gene flow between the populations over many generations, would that then ...
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Finding for evolution, comparing past flower numbers with present

In a hypothetical species of butterfly, wing spots are controlled by a single locus where BB individuals have blue spots, YY individuals have yellow spots, and BY individuals have green spots. Ten ...
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Why has grey hair evolved?

A vast majority of humans get at least some grey hair as they age. As far as I know this applies to both genders and all races. Presumably this means that at least some grey haired humans have ...
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Did Darwin ever reach the conclusion that selection will remove variation?

According to simple models of selection the genetic variance in a population should be reduced by selection. (Fisher's fundamental theorem states that the rate at which a population can evolve is ...
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Book on the history of Darwin's discoveries and development of his theory

This question is a book request. I am wondering if there are any books with these elements: Tells the history of Darwin's discoveries. Captures Darwin's changing views of the origins of species, ...
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Cell-level selection and inheritance of acquired mutations

I was reading about different levels of selection in Ridley's Evolution textbook (chapter on units of evolution) and saw that some organisms e.g. carrots are not Weismannist i.e. don't have separate ...
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Is it possible to calculate the evolutionary response to nonlinear selection gradient as a change in variance of phenotypes?

I often see the breeders equation written like this: $R = h^2s = \frac{V_a}{V_z}s = V_a\beta$ or $\Delta \bar z = G\beta$ But is it possible to get something like this: $\Delta \sigma_z = G\...
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Why do heterozygous individuals have increased resistance to malaria?

I am aware that there is such a thing called heterozygous advantage, which is due to the presence of a certain single allele, and that an example of this could be with "sickle-cell anemia". I am ...
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Have scientists ever produce a new species in laboratory by means of natural selection?

I was wondering, if scientists ever produce a more complex species from a less complex species by means of natural selection? I imagine something like, bacteria which can't photosynthesis and oxygen (...
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Do beneficial viruses exist? If so, what examples are there?

Typically, people call viruses some kind of organic compounds that cannot reproduce autonomously and which lower the fitness of their hosts. Even the word "virus" means "venom" in Latin. But from the ...
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What to call a trait that has current utility but unclear evolutionary origin?

I'm looking for a commonly used term to describe a trait that has clear current utility but an evolutionary origin that is uncertain and that we do not necessarily wish to emphasize in our description ...
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Killing more attractive mates — intersexual selection strategy? [closed]

Is this the affinity or core part of intersexual selection (males fighting for access to females)? If females are bound to flock to objectively more attractive man 'A' in the majority of cases, would ...
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Where are the evolutionary “inbetweeners”? [closed]

The problem I've always had with evolution is the actual lack of variation between animals. More specifically, the lack of observable gradual change between species. Take for example the hammerhead ...
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Background selection and hitchhiking effect

As I read the maintenance or removal of an allele from a population is dependent upon the alleles in its linkage group; so, when an advantageous mutation occurs in the population, variation in nearby ...
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Does natural selection apply to entire populations as it does to individual organisms?

The context: the other day I was reading an article about a peculiar species of ant that when threatened by a predator would “explode” in order to help protect the rest of the colony, although it ...
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Impact of Natural Selection on Population Size

I have conducted a lab with my IB Biology 11 class, regarding changes in allele frequencies within generations overseeing the natural selection of an advantageous phenotype. We were looking to ...
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Can the theory of natural selection distinguish between two correlated phenotypic traits?

Consider the following two situations: A species X has trait $T_1$ that is gradually selected for by some characteristic $E_1$ in some ecological niche but it turns out that the genes for $T_1$ also "...
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Many black people I've met have bigger lips than white people, why? [duplicate]

I noticed that many black-ish people I've met have bigger lips than the white-ish people I've met. However, not all black-ish people have big lips. Is there any explanations in terms of natural ...
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Selective pressure for reduced rates of growth and maturity in primates

Humans are somewhat notable for the slow rate at which they grow and reach physical maturity. Some related primates also take over a decade to reach sexual maturity. However, many mammals – ...
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How could a species be engineered to go extinct?

Non-biology background here. I read this very interesting article: https://www.wired.com/story/crispr-eradicate-invasive-species/ However I am having a hard time wrapping my head around something: ...
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Why does the slope of parent-offspring regression equals the heritability in the narrow sense?

Background ---- Notations and assumptions ---- let $W_{ij}$ be the fitness associated to the genotype $AiAj$. $x$ is the frequency of the allele $A1$ in the population. The frequency of the allele $...