Questions tagged [evolution]

Changes in the heritable attributes of populations of organisms over time. The mechanisms of evolution are mutation, migration, drift, and selection.

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What's the benefit of the average human body temperature?

Why would the body choose a resting temperature of 36.1c to 37.2c? It seems a very inefficient mechanism of survival considering the typical ambient temperatures on Earth. If there is a benefit to ...
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How does rate of evolution/innovation scale with population size?

I understand that there will be many other factors that affect rate of evolution/innovation. However, other things being equal, how will the rate of evolution vary between two populations of different ...
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History: Do evolutionary and ecological processes occur at the same timescales?

Classically, it was thought that evolutionary processes occurred at a much slower pace than demographic/ecological processes. Nobody, ever thought about incorporating both processes into the same ...
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Randomness in living systems

The point of my question is not to talk about events that are uncontrolled by living organisms. My question is about controlled randomness, or I'd like to say adaptive random process. Process that are ...
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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 ...
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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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Why asexual reproduction?

When I took a course on genetics and evolution, I learned that recombination and sexual reproduction is advantageous compared to asexual reproduction. Sexual reproduction allows more combinations of ...
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Identity By Descent vs Identity By State

Background The concepts of Identity By Descent (IBD) vs Identity By State (IBS) are central in population genetics, yet I fail to fully wrap my head around the definitions. You can find examples ...
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Macroevolution vs. microevolution

Where is the line usually drawn between macroevolution and microevolution? I thought that, although similar processes govern both, the line was at the species level, with macroevolution being changes ...
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Main mechanism of the evolution of sexual dimorphism

Sexual dimorphism is very common and (normally) requires the evolution of sex-specific genetic variation/regulation so the genetic correlation between the sexes can be <1. Is there consensus as to ...
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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 ...
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Is there a theoretical maximum on the number of sexes a given species can have?

Background: To the best of my knowledge, most sexually-reproducing species of organism have two sexes, although there are also sexually-reproducing species of organism (flatworms come to mind) which ...
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Has a beneficial mutation ever been documented?

I am trying to find a case/study where scientists documented a mutation in an animal or human that was to the benefit of the host. The closest thing I have been able to find is sickle cell anemia (...
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Is our genome decaying (see “Genetic Entropy”), and, if so, is this evidence for our genome being “young”?

In the book Genetic Entropy & the Mystery of the Genome the author says that the genome cannot be old because the genome is "decaying". Decay is a very subjective term, but in this case he means ...
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Why don’t different organisms have nucleic acid genomes containing different bases and sugar?

All organisms contain genetic material. Be it DNA or RNA, both of them have a fixed pentose group (deoxyribose and ribose). Also they contain the same types of nitrogenous bases, Adenine, Thymine(or ...
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Is there selection against long proteins and long genes?

Background thought Titin and TTN Titin is the largest protein in the human genome with 33423 amino acids. Titin is coded by the gene TTN that must be at least $3 \cdot 33423 \approx 100kb$ long. ...
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What does completing the course of antibiotics accomplish?

This article from the WHO states: If you stop treatment early, there is a risk the antibiotics won’t have killed all the bacteria that made you sick and that it will mutate and become resistant. This ...
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Do humans have any biological adaptations to eating cooked food?

Humans have been cooking food for at least tens of thousands of years. The presumed reason why cooking took root in nearly all human cultures is that cooked food is easier to digest. However, cooking ...
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Do the claims in this paper have any degree of validity?

The paper The waiting time problem in a model hominin population talks about a problem of waiting time, etc. Is the methodology of this numerical simulation, and the conclusion right or is it wrong? ...
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Key points of Wagner's theory of innovation

What are the key points of Andreas Wagner's "theory of innovation" from his book The Origins of Evolutionary Innovations? Specifically: What is new in his theory? What problems in evolutionary ...
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What's the purpose of colorful mushrooms' caps?

What's the purpose for many mushrooms to have colorful caps? Is not it is in their interest to hide as well as possible? Or there are mushrooms that propagate by being eaten, like fruits? Why not all ...
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How does GC-content evolve?

Background GC-content refers to the frequency of base pairs that are either C or G in the genome, or in other words the number of GC base pairs divided by the addition of the number of GC base pairs ...
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Altruism in viscous (asexual) populations

The viscosity of a population is the tendency of offspring to remain near their place of birth. Taylor 1992 ("Altruism in viscous populations") provides a model to study how viscosity affects the ...
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Is there an “Adam and Eve” for each new trait during (not just human) evolution? [duplicate]

Do new beneficial mutation evolve simultaneously and independently with several individuals of the same specie or only with one specimen who then transfers it to all of the specie? In other words, ...
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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} =...
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Real-world examples of Darwinian extinction

Darwinian extinction (also known as "evolutionary suicide") refers to processes of selection-driven self-extinction, i.e. the cases where natural selection causes the extinction of an evolving ...
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How can just random mutations explain mimicry? [closed]

I have been reading this article on drug resistance which explained that how random mutations in a bacterial colony can lead to development of drug resistance among some organisms in that colony. A ...
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Are there evolutionary advantages for the bee sting to kill the bee?

The question title says it all: are there advantages for the sting of a bee to kill the bee? It seems to me getting rid of this would have only advantages, and might've been selected for if a mutation ...
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Questions about the evolution theory [closed]

I'm not sure whether I can ask those questions about evolution in one post or should separate them into multiple posts, but I am just curious about the evolutiontheory. (I am new here) Sorry for my ...
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What is the relationship between radiation and evolution?

There is always a certain amount of background radiation present, for example due to ionizing radiation from the sun and other stars. Also certain materials like granite may emit relatively large ...
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How did the first sexual animal come to exist? [closed]

I am more or less familiar with the evolution theory based on mutations. Now, starting with a nonsexual being, how did the first organism that reproduces sexually come to exist.
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How did the horned lizard evolve?

It's a lizard that has the ability to burst blood vessels in it's eyes and shoot blood as self defense. How can this behavior be explained evolutionary? Wouldn't it mean that there had to be some ...
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About what percent of mutations are not adaptive?

Many popular texts that discuss evolution and natural selection often mention that many (or most) mutations are bad (not adaptive). Have there been any studies on what the rough percentages are? (E.g....
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Dominance/recessivity of new mutations

What is the distribution/probability density function (PDF) of recessivity/dominance of new mutations? I very welcome any partial answer that does not give the whole PDF but just some information ...
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What are the minimum conditions required for “open-ended evolution”?

According to a paper about artificial life systems, the following four conditions have to be fulfilled for "open-ended evolution": Condition 1: A rule should be enforced that individuals must ...
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Examples of extant animals in a submature morphologically unstable evolutionary state?

I'm fascinated by evolutionary theory and the predictive aspect of it-the notion of an animal entering a strongly divergent state of evolution whereby it is evolving into a new form yet remains ...
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Effect on fitness of mutations

What is the distribution/probability density function (PDF) of impacts on fitness of new mutations? I very welcome any partial answer that does not give the whole PDF but just some information about ...
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Hardy-Weinberg sex linked formula

The "big five" assumptions are the ones listed in the main text. However, the basic formulation of Hardy-Weinberg equilibrium also relies on a few other assumptions; Allele and genotype frequencies ...
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I think evolution has goal [closed]

Richard Dawkins says evolution doesn't have any goal. But I think evolution has one. At the end evolution creates intelligent being. If we find another earth like planet evolution sould have the same ...
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Why human skin colour disprove natural selection? [duplicate]

Amount of melanin decides the darkness and fairness of skin. The darker the skin is, larger the heat energy it will absorb from sunlight. The lighter the skin is, less will be the heat energy absorbed....
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Evolution of long necks in giraffes

In this question, the OP uses giraffe necks as a supportive example of evolution. Is the mechanism described in this post accurate? At some point, I thought I remember hearing that giraffes did not ...
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What are the evolutionary niches differentiating an apple from a pear?

So, as far as I understand (basic) evolutionary theories, diversity is generated by "niching." That is, if there is an environmental factor that hasn't been fully used by any species to "profit" off, ...
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Is there an evolutionary advantage to crying when sad?

It seems as though the act of crying when sad does nothing to relieve that sadness. Is there an advantage to crying from an evolutionary perspective, or is it the end result of a different process? ...
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Why does the butterfly have a cocoon stage in its life cycle?

Why does the butterfly have a cocoon stage in its life cycle? It could have simply grown up within the egg/cocoon, and emerged as a butterfly. Instead it is first an egg, then a worm, then a chrysalis,...
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Cat's tail movement as an indicative of tension

It appears to me that tail's twitching in the cats indicates how much tension the individual is under. During a hunt, when a cat tries to stay invisible, while approaching a target it is almost ...
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Why would deer continue to cross a river full of crocodiles even though some of them have been killed?

I recently watched a clip on Discovery Channel, where I saw deer crossing a river full of crocodiles, ignoring the fact that some of them would have been killed doing so. Is there a possible ...
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Why can't we call dog breeds different species?

I understand this question might fall into opinion based, but I'm trying to write it so that it meets the "Many good questions generate some degree of opinion based on expert experience" part and not ...
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Why does so much variation exist within species?

My last phrasing of this question did not go down well, so I will try again. The genotype of species is not always the same. If you ask yourself why not all of these possible expressions except one ...
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Why is it beneficial for trees to grow that tall?

Why is it beneficial for trees to grow that tall? This sounds like a kid's question Mom, Dad... why are trees so tall? Costs and Benefits There are some obvious ...
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If Evolution Is In Progress, Why Fight Extinction?

Natural selection is a central tenet of evolution. However, most biologists seem determined to prevent the extinction of the species that have been selected against. Why is this? Preservation of ...

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