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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Is it possible that East Asians are a hybrid between modern and achaic humans?
As I understand it, all populations outside Africa have at least 2% Neanderthal ancestry. In eastern Asia and I think Papua New Guinea in particular that percentage could be more than 4%.
Now you also ...
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Is this scenario allopatric or sympatric speciation?
I stumbled over a speciation scenario but I am not able to say to which type it belongs. I guess for people more familiar with the theory it might be easy to tell.
I was reading about the fin whale (...
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Expected number of SNPs in a sample of size `k`
Consider a Wright-Fisher population of constant size $N$. We sample $k$ haplotypes in this population. What is the expected number of SNPs?
I think the answer should be in Watterson (1975) but it ...
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Inheritance of child behavior based on daily life experiences of the parent
Our brain is a large network of neurons connected with each other.Our daily experiences change how our neurons are connected.Some experiences create better connections between two neurons A and B and ...
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Does a virus that spreads more rapidly have less chance to evolve?
Now that the COVID-19 pandemic has been going on for a while, there are reports of many new variants, which have presumably arisen in the past year through mutation and spread through natural ...
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What reproductive advantage do superhydrophobic spores bring?
Clubmoss plants produce spores that are superhydrophobic, meaning they will not mix with water. When you drop water on top of a whole bunch of these spores, the water will form tiny water droplets on ...
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Does the bending of a tree's trunk in the wind stimulate and strengthen root growth?
Recently Southern California experienced extreme wind velocities and afterwards the news reported over 300 trees had fallen in San Diego County. I had either heard or read somewhere that the action of ...
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Do technological developments terminate the evolution of human species? [duplicate]
One of the most agreed upon mechanisms for evolution is natural selection. Changing environmental conditions necessitates development of variations that enable the survival of that particular species. ...
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Are mutation rates normally distributed? If not, what are they?
On average, there are 64 mutations per generation in the human genome. Is this constant, or can we expect variation in the number of mutations?
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An interesting paper on hunter-gatherer social dynamics and cooperation
I've read a paper long ago on the cooperativeness in the hunter-gatherer primitive societies. Their conclusion is that for hunters, cooperation dominates competition; for gatherers, competition ...
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Why have mammalian predators been so small compared to their prey compared to theropod dinosaur predators?
So this is different than the question of "why are megafaunal mammals smaller than dinosaurs", which I understand to be a combination of:
live birth limiting size (even sauropods had ...
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What motivates an organism to reproduce? [closed]
What is the biological factor (gene or something else in case of humans) which motivates an organism to reproduce?
By reproducing the evolutionary success of an organism increases. But why would an ...
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Trying to find information about intraspecific allelic expression divergence in recombinant individuals due to changes in the cis regulatory regions
I am trying to find any research articles or resources that focus on differences in expression levels at the allelic level due to changes in cis regulatory regions in recombinant individuals. For ...
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is there an assumption of homology?
Recently, i watched evolution vs creationism especially in islam view of evolution. There is one particular guy called subboor ahmad (he is muslim apologist). he claimed that there is an assumption of ...
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Why don't the female lions in a pride help their male lion to protect their children from other males?
I watched a dozen of videos taping the fights between male lions; none of them involve female lions assisting in the fight. It is also known that the male lion who take-over the pride will kill all ...
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What is the evolutionary origin of euphoria and dysphoria?
What kingdoms from the three domains haven't evolved something like the reward system in us? Couldn't we feel neutral all the time and undergo an involuntary push towards the right behavior instead, ...
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Could trophy hunting lead to deer evolving to lack antlers?
There was a recent paper in Science which showed that elephants are quickly evolving tusklessness because elephant hunting imposes selective pressure against having tusks:
Shane C. Campbell-Staton et ...
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Genetic differences between Africans and non-Africans due to cross-breeding with Neanderthals?
It is estimated that soon after the "out of Africa event" there was some interbreeding between Homo sapiens sapiens and Homo neanderthalensis. All non-African peoples are thought to have ...
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Which fish did modern tetrapods descend from?
Did modern tetrapods descend from Tiktaalik or Ichthyostega? While I understand that in terms of all tetrapods, the lineages of Tiktaalik and Ichthyostega both would be included, but I want to know if ...
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Can somebody explain why mouse and cow are the least related based on this sequenece alignment?
Answer key says out of the choices, the mouse and cow and the least related. Is it because they have the most number of differences out of the four choices? (Hedgehog/Horse is 5, dog/horse is 3, mouse/...
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Why are there so few organisms that are both photosynthetic and eat for energy?
Carnivorous plants don't count as they don't use their prey for energy. Photoheterotrophs don't seem to fit based on a quick read as they use light and carbon in the same reaction. I'm looking for ...
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Is there an example in evolution where a huge jump in evolution happened due to a dramatic mutation?
Here is a chicken that due to a mutation got 4 legs:
I wonder, are there examples, where such one-time dramatic mutational chages gave rise to a new species?
Are there species that appeared not due ...
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How well evolution is supported by experts? Are there acceptable scientific objection to evolution? [closed]
There are people in internet , with professional sounding voice , who claim that evolution is not scientifically possible (such as there is not enough time for evolution, or modern genetics has ...
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Did animals primarily evolve to differentiate UV-rich sky from UV-poor substrate OR did they evolve to see visible light? [duplicate]
I read two things that appear to contradict each other.
The reason humans only see light in the visible spectrum is likely related to the transmission of light waves through water: most infrared and ...
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How are ray finned and lobe finned fish are sister clades?
I think my previous questions may have been misinterpreted (I honestly was too tired to formulate what exactly I was confused about), so I’d like to elaborate on my confusion about the phylogeny of ...
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Is there any research on whether a choanozoan might have invaded a similar enough holozoan to make the first metazoan?
My mind was piqued by the idea of endosymbiosis of a bacterium penetrating the cell of an archaean being a precursor to the advent of eukaryotes. And I thought that perhaps something analogous to this ...
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What actually causes temporal isolation
Temporal isolation is caused when members of the same species are available to reproduce at the same time. How is such a phenomenon even possible, is it caused by mutations which lead to a certain ...
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Where does Darwin state his "principle of multiple utility"?
I have never heard of Darwin's 'principle of multiple utility', but several papers refer to it. For example, from Darwin at the molecular scale: selection and variance in electron tunnelling proteins ...
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How do we know that the DNA we share with other species (especially primates) isn't fully the result of transposable elements?
I recently read a couple studies that concluded the 25% of genetic similarity between cows and reptiles is actually primarily due to TEs (transposable elements) rather than common ancestry.
Here's the ...
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How do we logically infer large time scales using Molecular Clocks?
If molecular clocks are uses in genetics to determine the mutation rate of genes to estimate times speciation occurred between two or more life forms, are there genes that have mutation rates that we ...
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Why are mallards ornately green despite lack of sexual selection?
Mallards reproduce by group sex, with multiple males mating with a female against its will. This means that the common explanation of ornate birds evolving due to sexual selection isn’t applicable to ...
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Why are there no organisms with metal body parts, like weapons, bones, and armour? (Or are there?)
Reading this question, Why are there no wheeled animals?, I wondered why no organisms seem to make use of the tensile and other strengths of metal, as we do in metal tools and constructions. I am ...
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Did predators evolve eyes first?
I'm an engineer and biology is my weakest point, so please forgive if this question is dumb.
Lately I've been wondering, "Why do animals that have eyes tend to have exactly 2 of them?" The ...
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Why do Bactrian camels have two humps and dromedaries one?
Why has the Bactrian camel evolved to have two humps instead of the one that the dromedary has?
I searched on Google and I found nothing about it.
All I found was that the that humps store fat, that ...
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what are some examples of how evolution's limitations prevented species from climbing to the absolute highest peak on the fitness scale?
In this answer, the author argued that plants are green instead of red or any other color because of some limitations of the evolutionary process. what are other examples in which the physical and ...
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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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When did bison exchange smartness for larger skeletal muscles or a digestive system that can ferment grass?
Patricia Churchland (2019) writes:
From time to time, evolution favors a dumbing down; sacrifice some smartness in exchange for larger skeletal muscles, like bison, or for a digestive system that ...
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Flora and fauna of early homo sapiens environment?
Where can I find as much detail as possible on the flora and fauna (and perhaps geological structures too) between the time of the origin of Homo Sapiens say ~300kya to their "out of Africa" ...
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Intelligence without natural selection?
Natural selection is not the only driving force of evolution. There are other mechanisms such as genetic drift, mutations, gene flow, etc... To what extent can these different mechanisms (which don't ...
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Did snow leopards lose the ability to roar or never have it?
Since snow leopards are the only species in the genus Panthera that can't roar, was this something the others developed after snow leopards diverged or something that snow leopards lost?
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Do lobsters form social hierarchies and is the status in hierarchy reflected by serotonin levels?
In his book 12 rules for life Jordan Peterson claims that:
Consider serotonin, the chemical that governs posture and escape in the lobster. Low-
ranking lobsters produce comparatively low levels of ...
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Is Natural Selection like a Copy Editor?
I am stuck on a Homework Question. It says:
Evaluate the following statement: “Natural selection works like a copy
editor; it works only with
what is already present in a population.” (Note: ...
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Why is dimethyltryptamine (DMT) released during death?
Many times I've come across a theory that the meaning of life itself is procreation - we simply live in order to make our species exist as long as possible. In the light of this theory, units like ...
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Has Darwin's abominable mystery been solved or not?
When I research Darwin's abominable mystery, the abrupt origin and rapid diversification of the flowering plants during the Cretaceous, I read different conclusions about whether it has been solve or ...
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Are giraffes living on Calauit island an example of Island dwarfism?
When I traveled to Calauit island I was stricken by the small size of giraffes living there. The giraffes are the descendants of Africa animals imported in the 1970s.
Like Noah and the biblical ark, ...
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What is the origin of mammals X/Y sex determination system and what/when was the last common ancestor to possess these chromosomes?
I know many animals use an X/Y sex determination system, but not all of these animals use the same X/Y genes. That is to say the X/Y sex determination system has convergently evolved in many species, ...
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Impact of Natural Selection on Population Size [closed]
I have conducted a lab with my IB Biology 11 class, regarding changes in allele frequencies within generations overseeing the natural selection of an advantageous phenotype. We were looking to ...
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What factors have led to selection for intelligence in crows and rooks?
The Corvidae family could include some of the smartest species after primates. What could be the factors that differentiate them from other species of birds that have determined their potential for ...
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What evolutionary advantage do viruses have in host specificity?
Warning: I have almost no knowledge of biology past the high school level.
Viruses generally have three components: the DNA, the virus protein coat, and an outer membrane "decorated" with these ...
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Fisher's Geometric Model for Dummies
Fisher's geometric model is still today one of the most important and fundamental model in evolutionary biology but it seems to me that most student in evolutionary biology don't really understand it (...
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