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1500 questions
34
votes
1 answer
Can beavers control the direction a tree falls?
We humans can easily control the direction a tree falls by making a number of strategic cuts, essentially creating a hinge:
This prevents trees from falling on equipment and people and sets them up in a good location for the subsequent processing…
canadianer
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34
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5 answers
Is there an advantage to antibacterial soap?
There are plenty of different hand soaps out there, as well as hand sanitizers. Is there an advantage to soaps that claim that they're antibacterial vs soaps that just say soap?
In particular I'm looking at Softsoap who offers normal soap and…
SolarLunix
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34
votes
1 answer
How long do your eyes need to adapt to darkness and reach full contrast?
I heard you should wait some time until your eyes adapt to darkness and are able to see smallest luminosity differences, otherwise you might overlook faint objects in the ocular. Are there any rules of thumb here?
What about looking for 5 minutes on…
Hauser
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34
votes
3 answers
How long does it take for memory to disperse after death?
1: There seem to be cases where coma patients with a non-active brain (i.e. flat EEG) have regained full consciousness. => Apparently memory and knowledge are stored independent of brain activity.
2: There seem to be animals (e.g. hamsters) that can…
user6268
34
votes
4 answers
Why don't viruses cause wounds?
A simple mental model of a viral infection is that an infected cell emits a lot of virions and eventually dies. The emitted virions have a chance of infecting other cells. Nearby cells are at a higher risk of infection.
Based on this model, if one…
Daniel Darabos
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34
votes
8 answers
Do "shooting" animals exist?
The well-known cartoon imagery of porcupines shooting their quills at opponents in a fight is just that: a silly cartoon concept that isn't real. But it makes me wonder, does that mechanism exist elsewhere in nature?
Are there any animals whose…
Mason Wheeler
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33
votes
2 answers
Can a bacterium infect another bacterium?
I researched about it by searching on Google and reading some bacteriological articles, but I did not get any answer. I also asked some of my teachers, and they were also a bit confused. Some said that it is possible and others said not. So the…
biophilic
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33
votes
1 answer
How long will a vegetable live for after being harvested?
I understand this might depend on the types of vegetables, but is there an average or studied specifics? Does it die immediately? Is there a way to precisely diagnose death in plants? If so, what are the conditions for it?
Hector
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33
votes
5 answers
Why isn't Fluorine, or Neon, the final electron acceptor in cellular respiration?
I'm a Chemistry student learning about periodic trends. I know that in (many organisms') cellular respiration, oxygen serves as the final electron acceptor due to its high electronegativity.
However, applying the periodic trends, fluorine is more…
Thomas Dang
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33
votes
2 answers
What do butterflies eat?
I found a beautiful scarce-swallowtail butterfly in my storeroom, but it was kind of frozen and couldn't fly away. So, I put it on my terrace in the sun. After a little bit, it flew a few meters away and fell. I was wondering what could these beings…
Yves LaFayette
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33
votes
2 answers
Why doesn't blood remain on a mosquito's proboscis in quantities that could spread blood-borne diseases?
We know that HIV can't be transmitted by mosquitos, and nor can other highly virulent viruses that are transmitted through blood and bodily fluid exchanges, such as Ebola (thankfully!).
Marcus Junius Brutus asked an interesting question in a comment…
user56reinstatemonica8
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33
votes
1 answer
Why are many fruits sour?
Many fruits (like apples, berries, citrus fruits etc.) contain high levels of organic acids, especially malic acid and citric acid. Are there any evolutionary functions of those acids in ripe fruits? In unripe fruits the sour taste may protect…
Marta Cz-C
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33
votes
8 answers
Is there anything that is completely non-toxic to humans at any dose?
Lately I have seen a number of unrelated "scientific" debates over whether certain substances should be outlawed because they are toxic to humans. My initial, informal reaction is usually to respond that anything is toxic to humans if you give them…
KutuluMike
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33
votes
1 answer
What do you see when your eyes are closed?
If you are in pitch black and you close your eyes, you sometimes can see strange shapes of various colors. A lot of the time these shapes and colors change as you observe them. This phenomenon still occurs if you are not in complete darkness.
I am…
JonHerman
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33
votes
6 answers
Why are there species instead of a continuum of various animals?
As I understand it, various animal traits have to evolve gradually, but what happens to the species that are "neither here nor there"?
To put it differently, if a species evolved from another, it did so because it's somehow better, right? So why are…
Darwin
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