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1500 questions
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2 answers

Do all living humans literally descend from one ape?

In the opening chapter of Sapiens, Harari writes: Just 6 million years ago, a single female ape had two daughters. One became the ancestor of all chimpanzees, the other is our own grandmother. Is there evidence that this is literally true? There…
Philip
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Mathematical Modelling of Natural Selection

I'm a math undergrad looking for some papers on modelling the process of natural selection. The only paper I've been able to find is by the pre-eminent mathematician Herbert Wilf from 2010, There's Plenty of Time for Evolution Unfortunately, Wilf's…
tom
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Are there examples of cells with more than one nucleus?

I've always wondered why cells have only one nucleus, as having multiple would seemingly prevent mutation. Are there examples of organisms with multiple nucleuses? If not, is there a reason?
mcchucklezz
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Is a DNA molecule a single strand of polynucleotide or two of them linked together?

Our molecular biology teacher told us that a double helix of DNA was composed of two DNA molecules linked together by hydrogen bonds. The thing is, until now, I always thought a DNA molecule was composed of two strands, those being polynucleotides,…
justdoit
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Identify this insect, found in Central Vietnam, with long antennae, black wings, and red body

Last year this insect landed on my hand when visiting the My Son city ruins in Central Vietnam. I've been trying to identify the insect, but until now without result. Can you help me? Or do you know who could?
SiTan
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17
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What is the smallest number of amino acids required for life?

Is there any hypothesis on the minimum number of amino acids required for life?
John Smith
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Intrinsically disordered proteins as potential drug targets

Intrinsically disordered proteins (IDPs) are a class of proteins that do not adopt a stable secondary or tertiary structure under physiological conditions in vitro, but still have biological functions. Many IDPs are implicated in cancer,…
Gergana Vandova
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Why does yawning trigger tears?

I'm just wondering when I yawned, there are tears coming out from my eyes, which makes me look like I'm crying. So my question is how does yawning give out tears?
a.012p
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Are two colors (red + blue) necessary for LED grow lights, or would either color be sufficient?

Below are some chlorophyll absorption spectra from other answers here. There is strong absorption at both the blue/violet end, and the red end of the spectrum, and presumably both of these contribute to steps in water splitting used in…
uhoh
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Worm inside a millepede

I found a dead millipede lying on the ground in Wayand, Kerala (India). I put it in a bottle and brought it home. After around 5 hours a worm came out of it. It is about about 1.5 cm long and segmented. Any idea if its a larva of some…
AdDate
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1 answer

Help me identify this insect from Bangladesh

I have seen this insect flying literally everywhere in Dhaka city (Bangladesh) over the last two months. It's small -- around 1-1.5 inches long. It's not an agile flyer and can be easily grabbed by hand during flight.
Ahmed Abdullah
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What causes the development of antibiotic-resistant strains of bacteria?

I understand bacteria have become resistant to antibiotics due to selection pressures, but how do resistant bacteria process antibiotics when exposed to it, compared to non-resistant bacteria. Also, what research is being conducted to combat…
harpalss
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Why are there 2 copies of RNA in the HIV virion?

There are two copies of the RNA in the HIV virion. These are retroviruses. So, they can make cDNA from even just one copy using reverse transcriptase. What is the use of the other? Are both integrated into host chromosomes? My guesses are: To…
Polisetty
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Could a fetus properly develop in micro/zero-gravity?

I suppose another way of looking at the question is: how important is gravity for the development of mammal fetuses? And if things would go wrong, what sort of things would they be, and what would be the result?
Chris Cooper
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Why Crocodiles don't eat Hippos?

I have been following documentaries about crocodiles and amazingly, crocodiles and hippos apparently seem to live happily in the same pond together without attacking each other. Why is it so? Like no matter how strong hippo is, its soft skin is no…
Failed Scientist
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