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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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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At what point do organisms officially become characterized as “domesticated”?

Is there an agreed-upon definition for "domestication" that can be drawn at a particular point in an organism's evolution? Or is this term more of a continuous spectrum? To give an example, ...
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How frequent are selective sweeps?

Introduction Selective sweep is the most famous genetic signature of selection. We know of a number of classical examples of selective sweeps, some of them in humans. See the classical example of the ...
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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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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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Why might long telomeres be selected for in laboratory mice?

In a recent episode of The Portal, Eric Weinstein sits down with his brother Bret Weinstein to discuss Bret's Reserve-Capacity Hypothesis. It's an incredible story of scientific discovery and and ...
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Is natural selection actually random?

In the Theory of Evolution, two main factors take place: One is random, which are the different mutations that organisms' DNA suffer. This process adds genetic variability to a given population. The ...
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Why is selection less effective in small populations than in larger?

I can understand that the genetic drift has a higher impact on smaller populations, but what does it mean for the selection to be less effective in small populations than higher?
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Do any known viruses contain “junk” or parasitic genomic information?

After reading about so-called "mystery proteins" in this excellent summary of the coronavirus genome (and acknowledging that the "mystery" simply reflects our lack of knowledge about a very new virus),...
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Are there real world examples of one way isolation between two populations?

I know that for two populations A and B, there are situations in which there is a two way exchange of individuals between the populations, and there are situations in which there is no exchange of ...
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Does epigenetics suggest there is at least some element of truth to Lamarckism?

I am not a biologist. But googling "epigenetics lamarck", I find many different opinions: For: Lamarck rises from his grave, Epigenetics: Lamarck’s Revenge?, Darwin’s theory ... is incomplete without ...
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Is natural selection a force?

I often hear that natural selection, or simply, selection is a "force". e.g.: the forces of directional selection on correlated life history characters, and an adaptive topography ...
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Clarification regarding a statement in “The Selfish Gene” by Richard Dawkins

In the third chapter of The Selfish Gene: Immortal coils, Dr.Dawkins makes the following statement while arguing for the case that ultimately "the gene" as he defines it is the unit of natural ...
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What is the difference between disruptive, divergent and diversifying selection?

In our lab meeting we were chatting about divergent selection. I was confused at some point because I wasn't sure what was the meaning of this work in comparison to diversifying/disruptive and other ...
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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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Are mosquitoes attracted to blue lights in particular?

I've been confronting the fact since childhood that mosquitoes are attracted to lights, especially blue lights. Now I know that all insects including mosquitoes are attracted to bright light but I ...
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What is the difference between the evolution of fins in whales and fish?

For a homework assignment I received the following question: Which statement best explains the evolution of fins in whales and fish? a. The common ancestor of whales and fish possessed genes for ...
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Why are smaller mammals more prone to cancer and tumors

especially rats and mice usually develop cancer and tumors very fast, reducing their life expectancy. From an evolutionary point of view, how come that these mammals are so prone to cancer and tumors ...
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Does technological developments terminate the evolution of human species? [duplicate]

One of the most agreed upon mechanism for evolution is natural selection.Changing environmental conditions necessities development of variations that enable the survival of that particular species....
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Does natural selection still increase biological complexity?

I recently read The Selfish Gene by Richard Dawkins, which I found very interesting. In one of the last chapters, he gives multiple possible explanations to the question "Why did natural selection ...
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Is the frequency at which a species mutate affected by natural selection? [duplicate]

As per natural selection, is it safe to assume that some species will have it genetically encoded so that they produce a certain 'perfect' rate of mutation so that they can adapt to an environment ...
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How does natural selection explain sexual display?

As I understand it, animals sometimes grow more vibrant colors, bigger feathers, elaborate dances, build shiny nests, all to impress the other sex. However, these are all superfluous to survival -- ...
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Evolution of recurrent laryngeal nerve in a giraffe [closed]

Do natural selection and survival of the fittest explain the divergent length of the recurrent laryngeal nerve...centimeters in the human, 15 feet in the giraffe?
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Is evolution always unidirectional?

Is it possible, at least in theory, for a species to evolve into another species and then evolve back into the first species?
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What are the implications/predictions of the selfish gene theory?

Are there any testable predictions or implications of the selfish gene theory? Or it is just interesting interpretation of the observations/experimental data? If this theory is not falsifiable and ...
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Examples of animals who 'forget' their offspring

Occasionally on the news I read about young children dying in hot cars on a sunny day. Usually the article reports that the parent(s) 'forgot' about their children still being in the car. Obviously ...
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Who were the first authors to talk about local adaptation?

I was curious to read about what Darwin had to say about the existance of locally adapted subpopulations. I discovered to my surprise that the expressions and terms "local adaptation", "spatial ...
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What is the relationship between r/K strategy and filial infanticides?

In other words, is the frequency of killing one's own offspring among species dependent on their location on the r/K strategy spectrum?
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Why can't geese regurgitate food?

I saw this harrowing video on how barnacle goslings have to jump off very high cliffs because the parent's can't feed them. The death rate seems high. Why did natural selection come to favor jumping ...
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Discrete vs Continuous Replicator Dynamics

The replicator eqn in the case of discrete non-overlapping generations and asexual reproduction is given by the discrete replicator eqn: $$x_i(t+1) = x_i (t)\frac{f_i(t)}{\bar f (t)}$$ where $x_i$ is ...
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Why would low complexity regions be linked with relaxed selection?

I'm reading a text (Wagner, 2007) on identifying positive selection. In the paper, the author says that low complexity regions are known to be associated with the relaxed selection. I'm trying to ...
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Is variation a result of Evolution?

We know that the DNA copying mechanism that replicates DNA during cellular division is not 100% accurate and the resultant errors are the source of variation in the members of a population. At the ...
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Sharks, alligators and Gould's “random walk” theory

I was thinking about Stephen Jay Gould's view on evolution as pure "random walk" / Drunkard's Walk, increasing or decreasing complexity in basically random fashion, just limited by death if an ...
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Are there any evolutionary reasons for the different tree shapes? If so, What are they?

So we know there are a thousand types of trees with different shapes. We have Columnar shaped trees: Pyramidal or Conical shaped trees: Weeping shaped trees: And we also have Round, Vased, Open-...
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Do Traits Have to be Adaptive in Order to Survive?

I'm reading Michael Pollan's book 'How to Change Your Mind', which is largely about psychedelic mushrooms. In discussing the biology of the mushrooms, he writes: 'Even if psilocybin in mushrooms ...
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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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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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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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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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