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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Book for molecular biology comparative to major taxonomic groups
Want recommendation of books on molecular biology (or molecular cell biology), that elaborately compares the structures and phenomena in the major taxonomic groups.
For say, whenever studying about ...
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How did a plant evolve to know there were animals alive that would eat it's fruit when it decided to produce this fruit? [closed]
How did plants come to "know" there were animals alive that would eat it's fruit when it first produced this fruit?
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Did some senses evolve from other senses or are they considered independent?
Are there evolutionary connections between different senses, in such a way that one sense is evolved from the other or from a common root, e.g. the possibility that hearing and touch are derived from ...
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Fastest observed biologically evolution rate? [closed]
Fastest possible evolution rate?
What is the theoretically quickest evolution rate?
For example, I could calculate this as the number of offspring an E. coli colony can generate at once * (time ...
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How would you model the evolution of two genotypes across generations?
Say you have a genotype A that produces x offspring and another genotype B that produces y offspring, where x>y. These x offspring are of genotype A but with modest differences in fitness due to ...
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Did birds descend from a single or multiple species of dinosaur?
It seems like there are mixed results because sometimes I read about a single missing link, like an archaeopteryx that somehow single-handedly explains all modern-day birds, but then I see conflicting ...
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Location of microbes causing eliminated diseases
Do eliminated diseases like polio, smallpox etc still exist in locations they have been eliminated from or in the wild or did we just make them go extinct like the dodo?
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Is there a defined non-trivial chromosome number distribution for a given kingdom?
I'm pretty aware of the mechanisms for chromosome number evolution in specific groups (e.g. inside a given genus). Nevertheless, looking at a broader scale (e.g. in the Metazoa kingdom), is there a ...
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Origin of melatonin: oxidative stress defense OR circadian rhythm?
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Which functional role of melatonin came first?
Regulation of the circadian rhythm
Defense against oxidative stress
Other
Background
I was well aware of the important role melatonin plays ...
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Does science have an explanation of how the first "common ancestor" formed in evolution? [closed]
I always have this question on my mind and I need a better explanation on this. Does Charles Darwin's theory explain it or are there any other theories which explain it better than Charles Darwin's ...
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Examples of chromosome fusions
One of the best "smoking gun" pieces of evidence of humans' close relation to chimpanzees, gorillas and orangutans is that human chromosome 2 is a fusion of two primate chromosomes, with a double ...
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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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Why has malaria only now started to develop resistance against artemisinin?
Why has malaria only now started to develop resistance against artemisinin, considering the compound has been in use for about two millennia in its herbal form in China?
The WHO has reported:
In ...
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Are there any half-evolved animals alive today? [closed]
I know that there are animals that are "simpler" than other animals but are there any that are half-evolved? Are there any animals with half-evolved functions, like arms, legs, etc?
This was part of ...
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Septic Shock: I'll kill myself before you kill me
Most of the deaths caused by extracellular bacteria don't actually result directly form their action. Rather, it results from an overreaction of the immune system to antigens such as LPS and LTA (...
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First infection of malaria
As I know Plasmodium falciperum survive in either a host animal, human or mosquitoes.
But how does malaria come to infect either of them initially?
I am interested in knowing evolution of malaria. ...
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How many proteins are in the Earth's proteome? [closed]
Humans alone have thousands of proteins. With that in mind, it seems like the total number of proteins among all species would be very large.
Are there any available estimates for how many proteins ...
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Why were wisdom teeth not eliminated by evolution? [duplicate]
Supposedly evolution was very efficient and evolved many human proteins over a few thousand generations. Yet obvious detrimental traits like wisdom teeth remained. Why?
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Protein in fruits
Why do fruits have such a low protein content (with a few exceptions) ? Don't seeds need protein while growing up? In comparison, the egg of a hen contains lots of protein, used to make a chick.
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Recycling and storage of nitrogen from breakdown of macromolecules?
If nitrogen is so important (it's a constituent of both proteins and nucleic acids), why are animals still throwing them out, and needing to eat it again? Is it true that in almost a billion years of ...
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Reference to hypothesis about breast sexual attractiveness?
Some time ago there was a hypothesis published,suggesting evolution made breasts mimic buttocks for either primitive men being attracted to women when they started to walk on two legs, or to ...
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Are humans the only mammals that are known to display homosexuality?
REQUEST: In this post I do not refer to, nor do I encourage reference to, any ethical/moral/emotional aspects of homosexuality. So please don't start an pro/anti- LGBT campaign in the comments section....
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Assumptions of Hardy-Weinberg rule
The post Solving Hardy Weinberg problems offers an easy explanation of Hardy-Weinberg rule. The current top answer explicitly does not talk about the assumptions of Hardy-Weinberg. A model makes sense ...
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Why do (almost) all energy carriers contain adenine?
Unlike this question which is specific to just ATP, this one includes all energy carriers.
When thinking of common energy carrying molecules, I can think of Adenosine triphosphate (ATP), Nicotinamide ...
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Why are monocotyledonous plants considered more evolved than dicotyledonous? [closed]
Why are the following characteristics advantageous for a plant?
to have atactostele instead of eustele
to have less stamens
to lose secondary growth
to switch to anemophily pollination (also if it's ...
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How do similar environments on islands in close proximity result in allopatric speciation?
I would like to ask a question on the very classic example of allopatric speciation seen in the Galapagos finches. Adaptive radiation occurred because the finches flew from island to island, so there ...
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Significance of lip end curve
What is significance of curve at point where lips meet, how it is determined and what effects it has on attraction and other factors? For some people it is a downward curve, for others it's an upward ...
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What is the best food to eat at this type of day since it is so vey very late? [closed]
Best food to eat? In this time of the day because it's late very soon to be
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Hybridization in Darwin's finches is rare or frequent?
I've talked to a couple of researchers today and read recent articles on the subject of hybridization of Darwin's finches. I'm confused about the consensus in the scientific community.
First, I was ...
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Why is uracil, rather than thymine, used in RNA?
This question was posed on SE Biology some time ago, but all the answers, including the accepted one, answered a different question instead: “Why is thymine, rather than uracil, used in DNA?”. I ...
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Are we going against nature? [closed]
Nature selects those who leave more progeny (reproductively fit) according to natural selection. But nowadays we are going in for family planning. So are we in a way going against Nature?
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Do species ever go extinct by becoming too successful?
Are there examples of species that have driven themselves into extinction by being too good at what they are doing? Like a predator that evolves to hunt so efficiently that it kills all it's prey and ...
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Why do human females have periods?
Why do human women have periods when most animals don't? It is known that the unfertilized egg needs to be shed from the uterus. But why shed the whole endometrium? Why didn't evolution put ...
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When do fireflies glow in their lifetime?
Does a firefly glow only when adult or larva? Or does it glow during its whole life. By glowing, I mean that they glow only when they require, not all the time.
Is there a reason (evolutionary ...
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Why are deciduous teeth shed? [duplicate]
Why do we have two sets of teeth? Why do earlier shed and new teeth replace them? In humans, kids do not have any need for replacement of the teeth. Why don't the milk teeth grow themselves? Or why ...
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Parents that eat their own children
I am told that there are some species, like fish or rabbits, that if let, will eat their own children. If this is true, how does a species like this exist? Shouldn't the fact that they kill their own ...
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What is the biological potential for vision of wavelengths outside the human visual range?
Humans eyes have evolved to perceive light only between approximately 350-700nm, because that form of light is most common to our lifes. Other animals can perceive lights with slightly different ...
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How did the felines get to America?
I don't know if the felines got originated on America or on Africa, but I do know there are species of cat in America and Africa that belong to the same family and genus (Felidae & Panthera).
How ...
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Why are we (humans) more likely to help people genetically related to us than people who are not? [closed]
Question. Why are we (humans) more likely to help people genetically related to us than people who are not?
My understanding of this question as follows:
Because the reproduction of people ...
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What's the percentage similarity between human individuals (and other primates) when comparing only exons?
In popular science books and articles, I often see it stated that humans are >99 % similar to each other (wikipedia has it a 99.5 %, referencing Craig Venter and this PLOS Biology article) and ~96-99 %...
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Why do female humans invest more in parental care than male humans, from an evolutionary standpoint? [closed]
As the question title suggests, why do female humans invest more in parental care than male humans, from an evolutionary standpoint?
My guess is that the crux of this that males and females have ...
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why has evolution favored sexual reproduction using two mates over sexual reproduction using three mates?
Many animals species require two members — a male and a female — to sexually reproduce. Why has nature (or the process of evolution) chosen to favor the form of sexual reproduction which requires two ...
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Does it make sense to classify all humans in a single species?
For what biological reasons do we consider that all human beings belong to the same species?
A Thai and a Nigerian share a common ancestor that is 140,000 years old (see Gravel et al. 2010 and this ...
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is there any theory about why life evolved to have DNA with 4 different bases and not 6 or other number like in organisms created with artificial DNA? [duplicate]
If organisms can carry DNA with 6 bases which supposedly stores increased genetic information, why living organisms evolved to have DNA made of 4 bases and not 6 or other number? is there any theory ...
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When analyzing whether selection favors an allele that allocates indiscriminately, should the initial frequency of the allele be considered?
For example, Refardt, Bergmiller & Kummerli (Proceedings Royal Society-B, 2013; http://rspb.royalsocietypublishing.org/content/royprsb/280/1759/20123035.full.pdf)
model bacteria that have been ...
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Why are some animals so much more intelligent than others? [closed]
From what I found many biologists state that animals living in large social groups (elephants, primates, cetaceans etc.) have a tendency for improved cognitive abilities. Yet at the same time there ...
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Can an exotic species be also endemic?
While talking about the evolution and conservation of dingoes in Australia, someone asked an interesting question:
Can I define the dingo as an endemic species?
That question, despite apparently ...
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Why do plants not have fat cells, and store their reserves in vacuoles instead?
Why don't plants have fat cells, but instead store reserves in vacuoles. And vice versa, why do humans feature fat cells instead of depositing storage molecules in vacuoles?
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Source for an upper bound in the number of genes based on mutation rates
So I've found myself referring in an answer once again to the idea that complexity (insofar as it's a quantity for which "number of genes" is a proxy) has an upper bound, limited by Muller's ratchet-...
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Why should evolution not be equated with progress?
My science textbook says this:
Evolution should not be equated with progress. In fact, there is no real 'progress' in the idea of evolution. Evolution is simply the generation of diversity and the ...