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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A theory about the possible connection between protists and first animalia
I learnt that animalia kingdom taxon creates can be either microanimals or (nonmicro)animals.
I understand that while it is controversial how a first cell was formed (or appeared) in earth, it is ...
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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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Thermophilic plants which are also halophilic?
I know that in botany there is a wide classification for plants that can survive in hot deserts (semi-arid or arid) and harsh climates such as 4-season countries with a tendency to droughts each year (...
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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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Did death evolve to reduce inbreeding? [duplicate]
Did death evolve as a way to reduce inbreeding?
Obviously givne answer doesn't cover this.
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Causes of different patterns of speciation within lineages
Over the course of evolution, some lineages divide repeatedly into sublineages of comparable size (I suppose this is what's meant by a radiation), while others form a grade leading to a single large ...
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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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How did the woodpecker's tongue evolve? Is not is simply impossible? [closed]
How the tongue got wrapped that way? What were the intermediate stages?
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Book recommendations on the evolution of trees
Trees have been around for hundreds of millions of years, since the first "true wood" evolved during the Devonian period ~400M years ago. This means we have fossilized wood in the form of tree ferns, ...
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What factors led to the evolution of humans in Africa rather than the New World? [closed]
I learnt at the zoo that the ancestor of monkeys existed in the Africa/South America supercontinent, but then took different paths once the two continents diverged:
Old World monkeys lost their ...
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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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1answer
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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 difference between atavism and retrogressive evolution?
It seems like both concepts talk about the re-appearance of primitive characters, and I'm quite confused about the difference between them. Any help is appreciated.
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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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How would have RUBISCO evolved if photorespiration had occurred in early life?
It is said that when RUBISCO evolved, the atmosphere was high in carbon dioxide with very little oxygen. Because of this, photorespiration never occurred and there was no selection pressure against it....
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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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Characteristics of a giant squid’s skin
Is the skin of a giant squid/colossal squid similar to the common squid? Does it possess chromatophores to change color? Or did it lose that ability because of the depth at which it resides or due to ...
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What is the evolutionary advantage of the Mane?
Horses, Donkeys, Antilopes and Bovines seem to have an evolutionary advantage in growing masses of hair on top (and sometimes below) the neck. Is that to hinder predators biting?
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Why is facial symmetry of the opposite sex attractive?
Why do we give so much importance to the symmetry of face in the opposite sex? Why do we yearn to reproduce with a person with a beautiful face? How is it important for survival, if at all? Is there a ...
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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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Why do komodo dragons have covered teeth?
Apparently komodo dragons have a layer of gum over their teeth and often bleed from the mouths because of this layer being lacerated when they bite. Does this layer of gum serve any evolutionary ...
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Why have ground beetles never evolved the ability to get back up?
This may seem like a funny question, but I've seen so many ground beetles upside down on the floor and wondered why they've never evolved the ability to get back up. Wouldn't something like this ...
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How does antagnostic coevolution work in ducks?
I recently learned that in ducks, the penis and vagina have coevolved: the vagina of the female ducks gets dead-end sacs and clockwise coils; the penis of male ducks become longest and its morphology ...
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Inheritance percentiles
I am aware that the average DNA contribution from each grandparent is 25%, while the possible range is 0%-50%. I found a source citing 18%-32% as the "normal" range but this was undefined. I assume ...
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Does intelligence depend more on environment than on genetic factors? [duplicate]
Many have argued that the test of IQ is simply a test of language. The application of the test consists of asking a number of questions. The person should understand the question presented to them and ...
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What causes the elongation of Genome down the evolutionary time line [closed]
Theory of natural evolution says that complex life forms arose from simpler ones e.g. starting from Eubacteria to modern day multicellular eukaryotes. {If we try to reduce these changes happening at ...
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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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Is recapitulation theory correct? [duplicate]
Most school books still say that recapitulation is an evidence of evolution but as far as I know it has been proved wrong so why is it being still taught? Has it got any sort of relevance?
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Were there any vertebrates with 6 or more limbs?
My question is actually a bit more broad than what's in the title, but I don't know how to put it succinctly. When I was trying to find the answer to that question, I found that all known terrestrial ...
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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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Who invented dN/dS?
I am writing a paper, and I want to refer to the original paper that coined the term dN/dS (or Ka/Ks for that matter). I have found early works on dN and dS (like Miyata and Yasunaga 1980), but cannot ...
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Comparative evolutionary study: is amino acid or nucleotide comparison more useful?
I am a high school student and am currently learning about evolutionary relationship study in biology.
My teacher said that a comparative study of amino acid sequences is more useful than a ...
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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-...
