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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Will all bacteria become resistant against all antibiotics in the long term?

(I asked the same at medicalsciences beta, but I expect a quite different perspective on it here) This is about bacteria that can infect humans, and their multi-resistance. The evolution of bacteria ...
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Have we found any other life form outside our planet?

I'm not asking about the possibility of formation of life on other planets instead has there been any real evidence of life(such as micro organisms or even very basic structures) that might suggest an ...
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Evolution history of virus tracing

How do biologist trace evolutionary history of virus, is there any article on this issue, e.g. how scientist got to know that coronavirus evolved from bat or camel or pig?
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Will the sex ratio of chickens become favourable to females?

As male chickens are killed after birth in mass farming. Will being male become a negative evolutionary trait, that is to say will females become more likely as male death is more likely.
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What does it mean for there to be no correlation between phylogenetic independent contrast?

I am testing the correlation between two physiological parameters in plants using the pic function in R. I am a bit stuck on the interpretation of the phylogenetic independent contrast (PIC). Without ...
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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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Why doesn't evolution converge on perfection? [duplicate]

I got to know about an organism called "Tardigrade(water bear)" which is an extremely hardy organism and can survive in most conditions. My question is that if the aim of life in general is to ...
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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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What might earlier versions of caddisfly shelter-building behavior have looked like?

The caddisfly has an amazing ability to build armor for itself by using a self-produced underwater glue to hold together pebbles: https://www.youtube.com/watch?v=Z3BHrzDHoYo. How could this behavior ...
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What is the oval shaped bone in the heads of some fishes?

I had a dish of fish and found 2 oval shaped nearly 1cm long bones in its head.What help does it do to the fish? what is its name? I have clicked the picture myself .
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How many generations are required for a specific neutral mutation to reach fixation?

In population genetics, the term “time to fixation” is defined as the time it takes for a specific mutation to appear in a population, plus the time required for this mutation to spread throughout ...
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What are the disadvantages of myelin

The myelination of axons has plenty of advantages. It increases signal speed in axons, and thereby reduces reaction times. This is, of course, very good for the survival of the animal in question. ...
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Evolution of the unique mating system of the scorpion Androctonus australis

Sperm transfer in the scorpion Androctonus australis involves a sclerotized spermatophore, which is formed in the paraxial organs of the male reproductive system. The right paraxial organ produces the ...
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How did interspecies reciprocity involving cleaner wrasses originate?

The small bluestreak cleaner wrasse (Labroides dimidiatus) will approach a much larger fish (for example a grouper such as Cephalopholis miniata), enter its mouth, and spends several minutes cleaning ...
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Is there any program or website that allows me to create phylogenetic trees without having to insert an already created dataset?

I asked a similar question on Quora before, but did not get any useful answers as the program the one answerer suggested turned out to have the exact same problems as all others I have found so far. ...
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Genetic variance for a behavioural trait among human populations

From this article from The Guardian: We instinctively assume that differences in behaviour that are in fact due to culture must be linked to – even caused by – characteristics of appearance. That ...
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What evolutionary advantages does a longer muzzle have against a shorter muzzle and vice versa

Basically I'm curious as to why when it comes to mammalian predators that some like say bears and canines tend to have longer muzzles than those like big cats. aside from their ancestors/evolutionary ...
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What's the evolutionary benefit of stress and cortisol? [closed]

Stress and cortisol lower immunity and increase hard disease. But why is it that way? If that's true then we shouldn't be stressful at all. What's the benefit of stress then? Why do we (and most ...
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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 Urea excretion a shared ancestral trait of amphibians and mammals relative to synapomorphic Uric Acid excretion in living reptiles?

Is the ancestral condition of prehistoric amphibians and early amniotes urea excretion? Would it follow then that the lineage leading to living reptiles went on to evolve uric acid excretion as a ...
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lifespan of Nautilus compared to other cephalopods

Most cephalopods live uncharacteristically short lifes compared to other creatures of their size and intelligence. The octopuses with the longest lifespan for example, the giant pacific octopus, only ...
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Can convergent evolution be used to explain similarity of genome of low and high Species e g. gorilla and human?

Example: 1) molecule Rhodopsin in halobacteria for producing energy from light. 2) molecule Rhodopsin for vision in human. These are said to be of different lineages and their high similarity are due ...
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Evolution of hunting behavior of parasitoid wasps

Wasps in the genus Pepsis lay their eggs in a specific region on a species of tarantula and their larvae eat the tarantula organs in a specific sequence to keep it alive as long as possible. How ...
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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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What is indirect vs direction selection of genes?

As the title suggests, what is the direct and indirect selection of genes. Couldn't find a straightforward answer. Is it the same as direct and indirect fitness?
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A theory about the possible connection between protists and first animalia

I learnt that organisms within Kingdom Animalia can be either microanimals or (nonmicro)animals. a microanimal is any Kingdom Animalia organism that in general cannot be seen by a human eye without ...
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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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A question about the clarity of certain terms

In the Red Queen's depiction, a population must evolve just to be able to survive its ever-evolving natural enemies. I'm trying to refer to a state in which many natural enemies have evolved adaptive ...
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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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Evolution of multicellular eggs

Which animals where the first in which ova were not simply released, but instead provided with some additional nutrition and/or protection in the form of a larger egg?
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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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Modern understanding Darwin's “correlation of variation”

In Variation under Domestication, Darwin makes several references to the concept of "correlation of variation": I will here only allude to what may be called correlated variation. Important changes ...
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life based on different elements [duplicate]

It is commonly proposed to look for life based on silicon, based on it's relative abundance and similarity to carbon. However, carbon and silicon are not completely interchangeable. The bond strength ...
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ELI5 what is true breeding?

In "Variation under Domestication", Darwin makes several references to the concept of true breeding: They believe that every race which breeds true, let the distinctive characters be ever so slight,...
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Have there been multiple aboriginal species of dogs?

In "Variation under Domestication", Darwin writes that: I may here state, that, looking to the domestic dogs of the whole world, I have, after a laborious collection of all known facts, come to the ...
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From DNA data, is it easier to conclude that chimpanzees are our close relative, than it is to do a paternity testing?

Well, today I was contemplating on how to explain evolution, approaching with the dialectic method. When it came to why chimpanzees and us being so close in the tree of evolution isn't outright absurd,...
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DNA of Different Species and The Fossil Record of Their Common Ancestor

Let me please be clear about something. I believe in evolution. The evidence and data are compelling and conclusive which makes it a very well-established theory. I'm seeking a certain evidence (if ...
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Has human intelligence evolved as a costly male signal?

In this video at 42:06, Daniel Dennett posits that our big brains are: The human artifice or version of the peacock's tail. Peacocks have sexual dimorphism - it's males who exhibit the costly ...
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What advantage does lactose have as the main sugar in milk?

Most organisms have lactose as their main sugar in their milk. What advantage does lactose give have over sucrose (Which is a common sugar in the plants, so it makes sense for it to be present in ...
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Why does music give you emotions?

Why do we feel emotions when we hear music? Click to see video How can a set of tones arranged in a specific order and timing make you feel sad or happy? I read that music can somehow trigger the ...
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Why did Darwin say “the misfortune to undertake”?

Why did Darwin say "the misfortune to undertake"? "Every naturalist who has had the misfortune to undertake the description of a group of highly varying organisms, has encountered cases (I speak ...
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How does a drastic change to the genome persist and spread?

I just read the article on songbirds in the November, 2019 Scientific American. The article explains that songbirds have an extra chromosome, called GRC (germ-line restricted chromosome) that other ...
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Brain evolution in the age of the caesarian

I have just been reading an account of the evolution of human intelligence in Matthew Syed’s recent book on diversity, called “Rebel Minds”. He is not the originator of this idea, but he suggests ...
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Is evolution a means to an end?

In "The Red Queen", Matt Ridley frequently argues that evolution is a means to an end, without providing much explanation for such a big statement. Is this a fact in biology? Do species mutate their ...
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Does animal blood, esp. human, really have similar salinity as ocean water, and does that prove anything about evolution?

It is an often-repeated claim that human, and in fact all animal blood is salty because we evolved from aquatic organisms, and that blood has a similar concentration of salts as ocean water, or at ...
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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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Are any genes over a billion years old?

Are there any genes (for any organism) for which we can say with confidence that they are over a billion years old?
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Why is synthesis of tetanospasmin advantageous to C. tetani?

The tetanospasmin is a neurotoxin synthesised by some strains of C. tetani. It is the factor causing tetanus, but what is its role for the bacteria itself? I do not believe the main objective of C. ...
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Mechanism to limit the exponential growth of the number of ancestors that are n-generations away from an organism?

The context is organisms with sexual reproduction, with 2 parents per organism. Construct the family tree of one such organism, back into geologic time. Take a(n) as being the number of ancestors ...
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Are all of my ancestors from 400 million years ago fish?

Say you have your family tree for the last 400 million years or so, back to the Devonian, the age of fishes. You take the set of ancestors that are about 400 million years old (which will be across ...

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