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1500 questions
39
votes
1 answer
Insect identification - Is this a bedbug?
This bug was found on a couch in Cape Girardeau, Missouri. The couch, and the two beds in the room show no signs of other bugs. Is this a bed bug that I should worry about or something harmless? It was slightly larger than a common tick.
Nick Criswell
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39
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2 answers
Do homing pigeons fly straight home or follow certain "highways"?
Homing pigeons (Columba livia) have been prized for their navigational abilities for thousands of years. They’ve served as messengers during war, as a means of long-distance communication, and as prized athletes in international races. (Source)
Do…
Katai
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39
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2 answers
What do ants do with human finger nails?
There is place in my house where I cut my nails. Here, there is an ant hole where an ant colony is seen.
Whenever I cut my nails from here, they take my nails inside their hole. I was wondering what they do with them.
Do they protect their houses…
Aishwarya Shiva
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39
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5 answers
Why do we age? or Do we have a theory of senescence?
There seem to be a number of ideas about why we age. Hypotheses include the gradual accumulation of cell metabolic products affecting organism function and the reduction of telomere length during cell division.
My hand-wavey idea would be "wear and…
Poshpaws
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39
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2 answers
Is there evidence that some non-human species perform sexual selection based primarily on intelligence? How do they do this?
I'm a biology amateur, but it seems like sexual selection is almost always performed based on physical characteristics, the outcome of physical contests, or some sort elaborate courtship. But do any non Homo-Sapiens perform sexual selection based on…
Gordon Gustafson
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39
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1 answer
How does laughing gas (N₂O) work?
Laughing gas (N2O), well, makes people laugh.
How does just a gas make us do that, there has to be some hormones at work...
So, I wanted to know how this works? What is the mechanism?
Ashu
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39
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3 answers
What is the difference between local and global sequence alignments?
There are a bunch of different alignment tools out there, and I don't want to get bogged down in the maths behind them as this not only between software but varies from software version to version.
There are two main divides in the programs; some…
James
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39
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1 answer
Are the antibodies developed by differing vaccines still the same?
If one person gets an mRNA vaccine that teaches their body to deal with a specific virus, and another person gets a similar but different mRNA vaccine, and another person gets a more "classic" vaccine with modified/weakened/dead virus cells, will…
Francis Bartkowiak
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38
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7 answers
Has there even been a clinical study where healthy volunteers consented to be infected with a pathogen?
I am curious if there has ever been a (modern) clinical study where a healthy volunteer was purposefully infected with a pathogen in order to test the effectiveness of a therapeutic or preventative measure (like a vaccine)?
If not, would the FDA…
Nova
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38
votes
5 answers
How does a baby deer stand the day it's born?
I know most creatures take time to learn some things.
Birds take some time to fly.
Human beings take some time walk or stand.
But in the case of the deer species, it's different. It can stand the same day it's born. Why is this so?
user30021
38
votes
1 answer
Why does a coconut have exactly three "holes"?
Why do coconuts have exactly three "holes", as seen in this picture?
A theory says:
As coconut is a sibling of palm, somehow long time ago, three palms were in a same husk. Based on evolution theory, it's how the coconut was born in the world with…
imwenyz
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38
votes
6 answers
Why do the two hemispheres of the brain control the opposite sides of the body?
Why does the left hemisphere control the right and the right hemisphere control the left? I googled it but didn't find a good answer regarding this. Could someone explain?
Does this adaptation help in the speed of transmission of nerve impulses?
lmathl
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38
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7 answers
Does red light preserve your night vision?
A number of companies have started marketing LED lamps that can be switched to a red mode. The claim is that red light is less harmful to one's night vision. Given that our eyes are less sensitive to red light, though, I'm not convinced that that…
Shep
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38
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1 answer
How does a cell sense its size?
Cells come in all sorts of sizes. How do they regulate their cell size to the point where similar cell types have a fairly mono-disperse size distribution?
Reasked from http://www.quora.com/How-Does-a-Cell-Know-Its-Size
bobthejoe
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37
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3 answers
Why do parasites sometimes kill their hosts?
It's bothered me for a while now. I understand why a parasitoid would do this, as it only temporarily requires the host, and that not all parasites kill their hosts.
There seems to be no evolutionary advantage in killing a host, because the parasite…
James
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