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Questions tagged [biology]

Biology is a natural science concerned with the study of life and living organisms, including their structure, function, growth, origin, evolution, distribution, and taxonomy.

175
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1answer
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Do cats always land on their feet?

Assuming a fall from a survivable height, will a cat always land on its feet? Has this been studied? Is there real data to back it up?
147
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2answers
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Do victims of rape have biological defenses that prevent pregnancy?

Pro life Rep. Todd Akin, who is running for Senate in Missouri, recently said: “If it’s a legitimate rape, the female body has ways to try to shut that whole thing down.” Needless to say, this ...
111
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3answers
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Is this picture showing an eagle flying upside-down genuine?

I found this picture on Facebook: It definitely doesn't come from a particularly credible source (I F***ing Love Science), but I'm curious if that picture is genuine. My mother claims that the legs,...
106
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1answer
8k views

Is eating rice harmful to birds?

There is an old custom to throw rice at the wedding couple when they leave the church after the ceremony. But now I have heard from several people that you should not throw rice because birds will eat ...
87
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2answers
14k views

Are 30% of human embryos “spontaneously aborted”?

From Richard Dawkins on Feb 1, 2019 How could I have failed to predict it? My tweet of the beautiful newt embryology film is already triggering the abortion nuts. Did you know, at least 30% of ...
76
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1answer
7k views

Do Ostriches bury their heads in the sand

I have always believed that Ostriches when frightened bury their heads in the sand. Upon closer re-examination of this belief, I came to the following conclusions: Ostriches typically live in arid ...
76
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5answers
13k views

Were people shorter in the middle ages?

In many castles or museums you'll find medieval armor, belonging to a knight. Those are often very small compared to the average human nowadays. I've heard this explained multiple times as being due ...
68
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1answer
14k views

Do drop bears exist?

A drop bear is a carnivorous bear that is known well for hanging in the tops of trees, and dropping down on potential prey to attack, hence the name. They eat medium-large mammals, often times many ...
63
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2answers
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Does dyeing elephant tusks help discourage poachers?

Recently, I've often seen this image claiming that some people are dying elephant tusks to prevent individuals from hunting them. Has this actually been done? Is it common? Initially, this seemed a ...
62
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2answers
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Does swatting/killing a bee cause the hive to attack?

I used to hear this all the time when I was growing up. Just ignore bees, don't swat at or try to kill them, because if they die, they'll send a "signal" to the hive that will attract dozens more. ...
60
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1answer
8k views

Do teenagers fall asleep and rise up later than kids or adults for biological reasons?

In a TED talk "Why school should start later for teens", Wendy Toxel made an assertion that teenagers naturally fall asleep and rise up a couple of hours later than children OR adults (related to ...
59
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4answers
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Is there any explanation for a near-death experience?

One idea I used to hear a lot about was that when people are near-death and saved by medical science that they sometimes see "a light at the end of a tunnel" in a vision. Today I read about an ...
56
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1answer
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Do human eyes grow after birth?

My friend just assured me that when a person is born, their eyes are at the size they will be for the rest of their life, or, that they do not grow. A Google for this question shows that it has been ...
52
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3answers
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Is the O-type blood used as a universal donor?

In biology classes at school I was taught that O can be a donor to all blood types (given matching Rh group and other details), and AB can receive transfusion from any type. Quick googling seems to ...
51
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2answers
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Are human fetal cells used to produce Pepsi?

A friend just came over and apparently Pepsi is made from people. Or, more specifically: The aborted human fetal cell line is known as “HEK-293,” and it is used to see how the human palate will ...
51
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3answers
6k views

Demonstrable and repeatable examples of evolution

Are there examples of evolution that can be demonstrated as proof that evolution occurs and is a useful mechanism for making predictions? Some examples that come to mind include: Animal husbandry (e....
49
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2answers
4k views

Do people need to drink 8 glasses of water a day?

Since I was a kid, I can't remember how many times I've heard that a healthy person needs to drink at least 8 glasses of water a day. There are definitely plenty of reasons to remain well-hydrated. ...
48
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3answers
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Russian scientist injects himself with 3.5 million-year-old bacteria, says he is now stronger and hasn't gotten ill in 2 years

I have found several articles regarding a Russian scientist, Anatoli Brouchkov: Anatoli Brouchkov is a soft-spoken guy with silver hair, and when he lets out a reserved chuckle, his eyes light up ...
48
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4answers
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Can anything remove fingerprints from your fingers?

Here's where it gets interesting; I don't mean erase them from an object, I mean from your fingers directly. Some people claim there is a way to do it, some people claim it's impossible. I have a ...
47
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1answer
8k views

During pregnancy, do babies send stem cells to their mothers to repair organ damage?

This picture is floating around the facebooks with no attribution to an original source (not even a source of the image): The image says: During pregnancy, if a mother suffers organ damage, the ...
46
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1answer
67k views

Does oxygen get you high enough to keep you calm during a plane crash?

Does oxygen get you high? If so, is the effect strong enough to keep the average person placid during a plane crash? From the movie Fight Club: Tyler Durden: [pointing at an emergency ...
46
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4answers
8k views

Do men think about sex every 7 seconds?

I'm sure most of us have heard at least a variation of this myth. Unfortunately I failed to find the original source. Was there actually a study that claimed this? A lot of the sites debunking this ...
45
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9answers
8k views

Is race a discredited scientific concept in biology?

I've heard lots of people say things like "race doesn't exist" and "race has no biological meaning." On the other hand, I've heard lots of disagreements too, from scientific popularizers like Steven ...
45
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2answers
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Is Genetically Modified food safe to consume?

What's the truth surrounding the popular idea that genetically modified food is dangerous to consume? There's entire websites and institutions dedicated to popularizing the alleged dangers of eating ...
44
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4answers
21k views

Do we lose most of our body heat through our heads?

If you didn't grow up in a tropical climate, you probably heard something like this as a child... Put on a hat before you go out because you lose the most heat through your head. Some say that ...
44
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3answers
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Is watering plants under a hot sun bad?

A couple of people have told me that it's a bad for plants to be watered in the middle of a sunny day, i.e. it's not just that you waste more water due to evaporation, but that there are actually bad ...
43
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1answer
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Is the Amazon rain forest man-made?

An article in the Atlantic quotes several experts who claim that the Amazon rainforest is the remnants of planted and cultivated orchards and farms, and that the land is not naturally conducive to ...
42
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1answer
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Do mosquitoes urinate on you when they bite you?

This is a claim that I have seen on several "Did You Know?" lists so far. They all state that when a mosquito bites you, they also urinate on you at the same time and that is what causes the area ...
41
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1answer
17k views

Was superglue invented to seal bullet injuries in Vietnam?

I cut myself recently and used superglue to seal the wound. I thought it was normal but when I tell people that act like I'm crazy. Then I tell them this story: Superglue was invented during the ...
41
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1answer
6k views

Does a human on a bicycle travel more efficiently than any other species?

Steve Jobs claimed on video that a bicycling human is more efficient at locomotion than any other species can manage. He repeated it separately on video, and in writing. The quote is still oft ...
40
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2answers
72k views

Does the DNA of one sperm contain 37.5 MB of information?

[Source] In an episode of the BBC show QI - Quite Interesting (Series J, Episode 1) Stephen Fry said: How much information do you think is in the DNA of one little sperm...? It's 37.5 MB... ...
39
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1answer
18k views

Is watching television in the dark harmful to your eyes?

This is obviously related to a few answered questions already here, namely: Does watching television damage the eyes? Is it harmful to your eyes to read in dim light? But the following question is ...
38
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2answers
46k views

Can an air-bubble in a syringe kill the patient?

I have heard of stories where, while giving injection to patient, a doctor forgot to remove all the air from the syringe. The patient died when the air reached to brain. Can injecting air into a vein ...
37
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2answers
14k views

Can you punch someone's nose into their brain?

A persistent tale in martial arts is that one can strike an unfortunate other on the nose in such a way that you drive the cartilege up into their brain. Is this possible? I think some points to ...
37
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1answer
8k views

Do colour-blind people see through certain kinds of camouflage?

I found this claim in Unweaving the Rainbow by Richard Dawkins. This is the Google Books link to the relevant page. Nobody knows whether or how this benefits them, but it may be suggestive that ...
36
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5answers
3k views

Are humans the only species that hunts down competitors, denies and destroys food for others?

In the book Ishmael, there's a passage that claims "Takers" (i.e. modern man) are the only thing in nature that hunt down competitors, destroy or otherwise deny someone else food. Are there strong ...
36
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1answer
19k views

Does a lobster feel little/no pain when boiled alive?

Image Source I have just read Cracked.com's "9 Ridiculous Cooking Myths You Probably Believe", that claims: [...] because [the lobster's] nervous system isn't very complex, so it's feeling little ...
36
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1answer
2k views

Can cats be herded?

On the site for this year's Amazing Meeting, there's a little joke about how organizing skeptics is like herding cats It's a common belief that (possibly) due to their strong will and independent ...
36
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2answers
13k views

Does your stomach shrink if you eat less?

I've heard people say this before; that eating less shrinks your stomach, making you desire less food in the future. When I looked it up online just now, the first few results conflict: Eating less ...
35
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2answers
127k views

Is this what “happiness looks like”?

This gif has been widely distributed on imgur/reddit/twitter/media and it is meant to represent Molecules of the protein myosin drag a ball of endorphins along an active filament into the inner ...
35
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1answer
7k views

Are most of the nutrients of vegetables and fruits contained in the peel?

Whenever peeling a fruit or vegetable, someone will usually comment (sarcastically), "that's where all the good stuff is", meaning vitamins, minerals, or whatever. Do the skins or peels of common ...
35
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1answer
20k views

Can you cause mosquitos to explode from drinking too much blood by flexing your muscles?

I have heard several times as I've grown up that you can flex your muscles to make mosquitos get stuck and explode. Looking around the web, I find several sources claiming the same. Q: If you flex ...
35
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1answer
8k views

Can you put on more weight than what you eat?

Someone once told me it is possible to have a net weight gain of more than what you eat. For example if you eat a quarter pounder burger you can potentially gain more than 1/4 pounds. Is this true?
34
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5answers
4k views

Does DNA add credibility to the theory of evolution?

I have yet to make up my mind regarding the theory of evolution. Whilst doing some reading on dnafish I read that DNA itself provides evidence for the theory of evolution: Yeast, trees, flowers, ...
34
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2answers
12k views

Did Michael Jackson artificially lighten his skin?

When it comes to superstars of his level, there always seem to be controversies, conspiracies, or some other mystery, and just one of the many surrounding Michael Jackson is that he for some reason ...
34
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1answer
4k views

Spontaneous human combustion, is it possible?

An article from Ireland dated January, 2011 shows that spontaneous human combustion (SHC)remains a hot topic among paranormalists... Spontaneous human combustion has been defined as: Spontaneous ...
34
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1answer
22k views

Reading while lying down is more strenuous (unhealthy) for eyes

My friend heard that reading while lying down is more strenuous (unhealthy) for eyes. I like reading in bed (books, tablet). Is there some study that confirms this hypothesis? I use two positions (...
33
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4answers
6k views

Is warm water more effective than cold water for washing one's hands?

When washing my hands, I was always told to use warm soapy water. However, is there any chemical or biological reason why warm soapy water is more effective to cold soapy water when trying to ...
33
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2answers
3k views

Do cats and dogs only see in grayscale?

Ask most anybody about dogs or cats, and they will repeat the claim that these animals are colorblind. To most, it means greyscale. Is it true that cats (ref 2) and dogs (ref 2, ref 3) only see in ...
33
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1answer
5k views

Can flatworms learn a maze by digesting other flatworms?

I recently watched the film Phantoms. A scientist in the movie claimed that flatworms were able to "consume" memories from other flatworms. The specific example was that of learning the solution to a ...