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1500 questions
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Can you get enough water by eating only fish?
Scenario: In a boat in the middle of the sea, no freshwater or food stores, no desalination equipment, no rain, but you can catch fish and eat it raw. Can you get enough water this way to survive, let's say for 14 days? (Enough clothes to protect…
Jan
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How can I find a complete human genome file?
I'm trying to figure out how I can download a file that represents the complete human DNA sequence. I don't care too much about the format – I'm able to write C++ code to parse it. FASTA seems like a simple format though. What I haven't figured out…
ABCD.ca
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Did we first have swimming birds or flying birds?
Looking at the swimming birds building nests just across my garden, I suddenly wondered how evolution came to swimming birds and whether flying birds started swimming or whether swimming bird like animals started flying.
What came first and when and…
Abel
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The evolutionary process in bird wings, especially with regard to winglets
In this answer on aviation.SE a comparison is made between the shapes of airplanes wings and the shapes of birds wings. It concludes with the following remark:
After all, no bird has winglets. Not a single one.
In addition to be a disputable…
Federico
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Is there an evolutionary advantage to crying when sad?
It seems as though the act of crying when sad does nothing to relieve that sadness. Is there an advantage to crying from an evolutionary perspective, or is it the end result of a different process? Also, why is there the same physiological reaction…
LanceLafontaine
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12
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Have any mutations or genetic loci been associated with exceptional longevity in humans?
Individuals that avoid age-related diseases into later life are known as 'exceptional survivors', and have increased longevity compared to their 'controls' (those that were born at a similar time, yet have 'aged' and died sooner). The Leiden Study…
Luke
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12
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2 answers
Is mammalian vision processed as a sequence of frames?
I often read that people believe that human vision has an inherent frames-per-second rate (FPS) that causes stroboscopic effects - such as seeing the spokes of a rotating wheel apparently rotating at a different speed or appearing stationary when…
RedGrittyBrick
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In which order did the cells of the immune system evolve?
Thinking about how complex the interactions between different types of immune system cells (T-helpers, T-Killers, Phagocytes, B-Cells etc.) are, it's fascinating how they all combine to get the desired effect.
However, I assume that they didn't…
Rory M
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Why does replication require primers while transcription does not?
In transcription, there is no need for any primer. I guess the basic mechanism of DNA polymerase & RNA polymerase is the same. So why does replication have the need for a primer?
anamitra ruj
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What are the frequency ranges of most marine mammal vocalizations?
I am trying to determine a list of frequency ranges into which marine mammal vocalizations fall.
Ideally, I would like a list showing where the most popular marine mammal vocalizations fall, followed by the species name. That being said, I only…
Spacey
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Mammal body density
Human body density is approximately 1 kg/l (same as fresh water) - which is not surprising (at first) given that we are 70% water, and is surprising (on a second thought), given that the other 30% can be just about anything (from the air in the…
sds
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What can the timing of human urination tell about the human's physical condition and circadian rhythms?
I've noticed a peculiar phenomenon. A subject drinks 400 ml of water, then observes time until the urge to urinate is felt. The time is 15 minutes. The subject releases water. 14 minutes later another urge to urinate is felt. The subject releases…
Alex Stone
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Does the use of "var", "x", and/or "ssp" in a scientific name provide specific information?
What exactly does it mean when a plant has a scientific name that specifies a vairety, for example Nothofagus solandri var. cliffortioides, or when the name includes an "x", as in Populus maximowiczii Henry x trichocarpa, Populus xcanadensis, or…
David LeBauer
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Why does Hunger lead to the aggressive behavior?
I have observed that frequently when people are hungry; they tend to get angry more easily on pointless issues. Does this mean that our fight or flight response is more active when a person is hungry? What is a possible reason for this? Is this…
katherinebridges
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Are all mutagens carcinogens?
Not all carcinogens are mutagens. Alcohol and estrogen, for example, does not damage DNA.
It's one of the assumptions of the Ames test that mutagenicity implies carcinogenicity, but is this always the case? I assumed that it was, but then I saw one…
Resonating
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