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1500 questions
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Is there a significant difference in sedentary calorie-burn between a thinker and non-thinker?
I've read that, on average, a sedentary female burns between 1,600 - 2,000 calories and a sedentary male burns between 2,000 and 2,500 calories. I've also read that the brain itself burns quite a few of these.
Let's say two people are exactly the…
AmagicalFishy
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Why are fruits so large compared to their seeds?
Why do many plants produce such large fruits(apples and strawberries,for example) if those contain only relatively small seeds?
matt
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Is there any biological reason that professional swimming is dominated by white people?
I suppose that the question should be turned around to "Why is it extremely rare to see black people competing in professional swimming?" because it is the absence of this phenotype while watching the Olympics that caused me to ask this…
ODP
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Why do people with Down syndrome get fewer cancers?
I'm coming across some conflicting information regarding the correlation between cancer incidents and trisomy 21. I read a report from nature that discusses how Downs are only a tenth as likely to develop cancers, but at the same time are 20x more…
rhill45
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Why does this illusion work?
This is another image I found on Google+
All lines are absolutely straight, parallel and perpendicular but why does it appear to have a curvature?
Related: How does this illusion work?
Green Noob
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Why insects are so energy-efficient while flying?
Why are insects so energy-efficient while flying? Is it because of their light weight and aerodynamics or due to very efficient biochemical transformations (food->energy)?
Adolfo Perez
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Name (and meaning of the absence) of the white semicircle at the base of the fingernail?
At the base of fingernail, there is a white semicircle (see on the first picture). But sometimes there isn't one.
My questions are: what is this white semicircle on the fingernail, and what causes it? What is the explanation when there it isn't on…
blackcornail
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What are the differences between cancer and tumour?
What are the differences between cancer and tumour? I mean is it in the DNA or shape or something else... And how can a benign tumour turn into a malignant tumour? The body has a lot of tumours all the time, however not all of them become cancerous,…
Malic Of Sdom
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Is there any recent evidence for the aquatic ape theory of human evolution?
The aquatic ape theory suggests that many features that distinguish humans from their nearest evolutionary relatives emerged because the ancestors of humans underwent a period when they were adapting to an aquatic or semiaquatic way of life, but…
c0zmic
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How much energy does a lion contain?
I was looking into the following problem:
Obviously, the solution lies in how much energy either can output per unit of time.
The total energy output of the sun is $3.8×10^{26} \frac{J}{s}$.
The number of lions alone pales in comparison…
Etheryte
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Why does the butterfly have a cocoon stage in its life cycle?
Why does the butterfly have a cocoon stage in its life cycle? It could have simply grown up within the egg/cocoon, and emerged as a butterfly. Instead it is first an egg, then a worm, then a chrysalis, and finally after some time a butterfly.
Everyone
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Is there a consensus on whether or not race exists on a biological level?
The most recent survey I could find was from 1985 which said that 16% of biologist disagreed that "[t]here are biological races in the species Homo sapiens."
I was wondering if there's been a change in this position.
Louis Waweru
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How old does a baby have to be before it can retain memories?
For most people (my earliest memories are of perhaps when I was 2 or so) their earliest memories would be when they were over a year old.
How old does the average baby have to be before it can retain memories?
Are there any preconditions that need…
Everyone
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Can dolphins actually communicate linguistically?
Humans use "language." By language, I mean the thing I am using right now to talk to you.
I know dolphins and orcas have very complex communication systems and also seem to process linguistic and gestural commands.
But do they have their own…
Stan Shunpike
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Is there any evolutionary advantage of selection of L-amino acid over D-amino acid?
After listening to a scientific talk, I had this question that why in the natural selection process, are the L-amino acids selected over the D- form. However, we still we produce D-amino acids; specifically in the brain there is a higher…
Arpit Mishra
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