Rank ignorance.

February 4, 2011 4:39 PM

Do human beings as a species, homo sapiens sapiens, have a strong body odor in their natural state? Anthropologists, biologists, informed laypeople, any way to get at the truth?

There are many body odor threads on the green. Rampant speculation as to why somebody stinks. Bad hygiene, medical conditions, laundry.

My question is different. At the zoo, when you pass cages full of animals, some species have no odor at all (that's detectable to humans from a distance of a few feet), but other cages stink to high heaven. Now I realize that all animals have some body odor, but I'm talking about the "high performers".

How about humans, in an uncivilized state, as we might have been 50,000 years ago?

We cannot take a modern street person, for example, because they frequently wear clothes soaked in urine, and that obviously is not exactly "in their natural state".

Anecdotally, we know that various individuals may have stronger/weaker body odor - a bit odd, seems to me, as I can't imagine such wide variability, among, for example, individual hyenas. We also hear, anecdotally claims that f.ex. people of different ethnic backgrounds have different levels of body odor (I have no idea how valid that is).

I'd imagine that to some degree it would be a function of diet. But what about the concept of hygiene? We don't talk about hyena hygiene, except for grooming behaviors which may impact odor. What about humans back in pre-historic times - running, active, sweating, but without recourse to soap. Historically, we know that in various societies in various time periods, people might rarely to never bathe (and there were even myths associated with it, like "bathing is unhealthy"), but again, things have been complicated by clothing which can absorb and amplify smells.

So, let us say we are strolling through a primeval forest:

a)suddenly we come across a terrific stench - our guide says "oh-oh, humans ahead!" "How far?" "Mere feet!" "A mile!" "Six miles!"

or

b)we stumble across a group of humans hiding in the bush, and we never smelled them!

I suppose it's also possible that to humans other humans will smell, but a cat might not, simply because we are sensitized to that smell evolutionarily.

In any case - is humanity closer to the hyenas in cages, or cats in cages?

posted by VikingSword to Science & Nature (25 answers total)

Humans sweat, hyenas don't. Bacteria consume our sweat and let off odors.
posted by dfriedman at 5:00 PM on February 4, 2011

Best answer: Louis Leakey thought human smell might have been powerful enough to serve a defensive function. Here's a very old (1979) Time article which mentions this and other ideas about human smells.
posted by Francolin at 5:01 PM on February 4, 2011 [1 favorite]

Response by poster: That's interesting, Francolin. From your link:

"The late anthropologist Louis Leakey suggested that body odor was a key evolutionary defense mechanism—predators may have attacked early humans only as a last resort because they smelled too bad to be good food."

Well, if accurate, that would answer the question. Humans really stink abominably. But, what did Leakey base his suggestion on? What kind of research proves his thesis? How did he know humans stank? Is this some kind of "common knowledge", or what?
posted by VikingSword at 5:15 PM on February 4, 2011 [1 favorite]

Wikipedia has a somewhat detailed article about human body odor.
posted by dfriedman at 5:17 PM on February 4, 2011

Response by poster: The other thing that makes me wonder - are we accultured to dislike body odor because using soap has become normative, or do we naturally abhor the smell? If the latter, then how did Leakey imagine early humans procreated, if they themselves were repelled by a stench so horrific it drove starving lions away. Homo sapiens skunkus? Are other species with strong body odor repelled by their own, or is it only repellent, to f.ex. predators, but perfume to them? This is a separate question to chemical signaling like pheromones, because as far as I understand, you don't actually necessarily smell the pheromones; then there are those who like the smell of the body during sex etc., but those again would be special circumstances, like f.ex. in animals in heat as a smell signal for procreation. All very complicated.
posted by VikingSword at 5:23 PM on February 4, 2011

There is some interesting discussion here (starting middle of p. 119).
posted by flug at 5:47 PM on February 4, 2011 [1 favorite]

The zoo cages that stink most to me are usually the large animals who need a huge territory--the elephants, the giraffes, the antelope and zebras (and so on). I wonder if, outside of zoos, those "high performers" don't have noticeable smell because they're not crammed into a too-small space.

As an example, zebra pens at a zoo smell--to me--like horses that are kept in too small a space. Farms that build up manure for any reason, especially because the horses live in stalls or small paddocks, definitely have that kind of smell. But a horse farm where the horses live in large pastures with at several acres per horse (or so) doesn't have the same smell about it. (Equids, by the way, since it's mentioned above, do sweat.) That's not the horses, that's waste buildup/disposal issues.

So I wonder if you're ascribing a reek associated with containment to strong animal BO.
posted by galadriel at 5:59 PM on February 4, 2011

Although you don't usually notice it at the distances in most zoos, gorillas and chimpanzees have a definate and not entirely unfamiliar body odor; they smell "sweaty", that sort of skunked-beer smell of a human who's been working hard for a long period, but with a twinge of "other".

My experiences in South America with some native tribes-folks seems to indicate that they don't smell like much of anything. Even though it's hot as balls and *I'm* sweating and stink like a skunk ape, the locals don't seem to sweat at all. But then again they were in and out of the river a lot, so they're very clean, too.
posted by The otter lady at 6:00 PM on February 4, 2011 [1 favorite]

I think this discussion is conflating body/sweat odor and excrement/urine odor. Animals with a large territory might use strong urine or excrement odor to mark territory, but do they really smell bad away from their waste sites? At a zoo, for example, are you smelling the animals' body or waste? In the wild, wouldn't the animals be further away from their own waste than in (some) zoo enclosures? Cats, for example, have terrible-smelling waste, but the animals themselves are very clean, and don't smell at all when they have a whole house to roam.
posted by amtho at 6:23 PM on February 4, 2011 [1 favorite]

Response by poster: Right. I didn't want to conflate this with the excrement/urine odor. Also, some animals rub themselves in various strong smelling substances (like humans and perfume!), and that's distinct from their ordinary body odor. Finally, some have special glands that they activate only on some objects for marking, again that's distinct from their own body odor. All of these are only tangentially connected with the human species (seems to me).
posted by VikingSword at 6:35 PM on February 4, 2011

I don't think we naturally abhor human body odor. I went on a month long sailing trip where no bathing occurred besides dipping very briefly into the cold atlantic and washing our hands. I wore the same clothes for a month. No deodorant. There were about 12 of us on a very small thirty foot pulling boat (this was outward bound) and nobody complained of body odor. We slept side by side like sardines on the boat and space was tight, so it certainly would have come up. When I was picked up by my parents and brother afterwards though, they thought I smelled awful. I think you just get used to it. It's all relative.
posted by smokingmonkey at 6:44 PM on February 4, 2011 [3 favorites]

Best answer: Okay, weird. I was just reading about this in Mary Roach's newest book.

NASA actually tested this for the Gemini and Apollo programs, as the early moon missions would involve around two weeks of non-stop travel with unwashed bodies in a small space. The sweat you produce (there are two different kinds!) is a good breeding ground for odor-causing bacteria, but your sweat is also somewhat anti-bacterial, so there's an upper limit as to how much odor you produce in that regard. Wearing clothing extends this capacity, as our clothes absorb about 95% of the oils and sweat we produce. After two weeks you're as crusty and greasy as you'll ever be.

The thing is, after eight days or so, you'll stop smelling it. Your body stops reacting to it and tunes it out as background noise.

From this, I would intimate that, yeah, we most likely had a hell of a musk as hunter/gatherers, but it's also just as likely that we didn't know about it.
posted by greenland at 6:44 PM on February 4, 2011 [7 favorites]

I also want to anecdotally object to the idea that human odors are by nature repellent to other humans. When I've noticed people being smelly (in a natural body odor kind of way, not in an artificially enhanced kind of way), I'd say I think they smell good about as often as I think they smell bad. Then again, I did spend a lot of time in 9th grade huddled up with a copy of the book this comes from - so maybe my appreciation for BO is acculturated. Or maybe the article is right and BO-replusion is acculturated.
posted by bubukaba at 7:00 PM on February 4, 2011 [1 favorite]

Best answer: I think that Louis Leakey was sort of speculating about why it was that humans, lacking sharp claws and teeth and other advantages, weren't hunted to extinction by apparently stronger animals, particularly big cats. The idea shows up in a 1967 letter, quoted here (but to whom it was addressed I don't know). So he was probably just imagining, in an informal, conversational way and late in his career, possible aids to human survival, and didn't pursue the idea, it seems. (I wonder why he suggested that lions would be sickened by an overwhelmingly not-good human smell. It does not seem like something that would bother them much.)
posted by Francolin at 7:13 PM on February 4, 2011

As a proud owner of five cats, I also have to say, people get used to odors pretty quickly. I am constantly paranoid that I've just gotten used to the cat box smell, and our friends are too polite to say anything. If everyone stank, then as social creatures, we'd be accustomed to the smell fairly quickly and probably wouldn't notice it. So no, I don't think we'd be repellent to each other, but other creatures, I could imagine so.
posted by Tooty McTootsalot at 7:34 PM on February 4, 2011 [1 favorite]

A friend of mine went on a gorilla safari in Rwanda and she said they smelled the gorillas WAY before they saw them, and not in a good way. I don't know how relevant that is, since gorillas have a lot more hair, but at least they are also primates...

I think people smell revolting after a few days of not showering, but I'm not going to pretend that there's no cultural element there.
posted by fingersandtoes at 7:37 PM on February 4, 2011

Personal experience: Since recently going almost entirely vegetarian (making vegan choices whenever I can) after being a hardcore carnivore for most of my life, I personally stink dramatically less than when I was eating meat & dairy daily.

My wife used to send me to the shower with finger-clenched nose, and not as a metaphor. She wouldn't let me get into bed without showering, leave the house without putting on deodorant, wear a shirt more than once, and oral sex could get... *AHEM* curtailed.

I recently informed her "Babe, I haven't put on deodorant for I think 3 weeks at this point". She was stunned, because we were in bed and I hadn't showered after a day out and about. And yeah, the difference was profound after a just couple of weeks settling into a plant-oriented diet. Smell less over all, smell less stinky when I do sweat, need to do laundry a little less often. And I think my sense of smell is starting to get attenuated to notice when someone has a animal-protein-heavy diet by how they smell.

Oh, and that "Vegetarians taste better" t-shirt... yeah, that's a snarky cannibalism comment. It's got NOTHING WHATSOEVER to do with oral sex. Nothing at all. ;-)

So yeah, diet has a profound affect on how someone smells.

THIS DATA POINT COST: $.02
posted by Pirate-Bartender-Zombie-Monkey at 7:53 PM on February 4, 2011

I understand that soap use is not the same as not washing. Nevertheless, soap use did not become common until the 1950s. For example, from the Ivory soap website:

The modern-day history of soap shows that soap use became widespread in industrialized regions because people began to understand the importance of cleanliness in controlling pathogenic diseases. In the late 19th century, the first commercial bars of soap were manufactured. The Victorians further advanced the popularity of soap as a priority not just as beautiful luxury fragranced gifts but also as own use items “Cleanliness is next to Godliness” was an important theme in Victorian social history and continued a long history of lavender scented soaps, potpourri, fragranced sachets, lavender oils, body lotions and many other gifts which today make up much of Heathcote and Ivory’s fragranced floral ranges, continuing an elegant and practical tradition started centuries back. Advertisements of soap shown all around America and Europe to boost the awareness of people about hygiene and health, including the famous Pears Baby Soap campaign brought the use of soap further into the public domain. Finally, by the 1950's, everyone considered soap as essential to personal hygiene.

I don't think we stank, but I'm guessing that the drastic changes in diet to processed foods has contributed to the stink. They had to push us to social anxiety through heavy advertisements to get us to use soap. If we really stank it wouldn't have taken such heroics.
posted by sockraticpielogue at 8:17 PM on February 4, 2011

At the zoo, when you pass cages full of animals, some species have no odor at all (that's detectable to humans from a distance of a few feet), but other cages stink to high heaven.

How do you know you're smelling the animals themselves and not their excrement/urine, which is also confined by the cage?
posted by desuetude at 8:41 PM on February 4, 2011

URF! attenuated = attuned
posted by Pirate-Bartender-Zombie-Monkey at 8:43 PM on February 4, 2011

Response by poster: How do you know you're smelling the animals themselves and not their excrement/urine, which is also confined by the cage?

Well, take the example of bears. Yes, the cage is rank. But the bear is pacing. And as he nears you, you can smell him quite distinctly, and it's not piss/shit, which you also have on offer and can smell when he paces away. The bear has his own special smell - although, of course I wonder if it's something to do with what he eats - for sure, for example, carrion has a strong smell, and if he ate that, or had to root about in carrion, he'd reek of that... I don't suppose he eats carrion at the zoo, but he may very well eat some other food of equally strong smell.

In any case, it's not simply urine/excrement. For example, foxes seem to have a very distinct smell, and that's also true of many other animals, while some cages are pretty/relatively odor-free.

Furthermore, you become familiar with different odors, the same way if you are at the hospital, you can tell after awhile, what is the smell of a cleaning agent vs other smells. Same with the zoo. You can tell what's the food, what's the animal and what are some of the other smells, urine/excrement etc.
posted by VikingSword at 8:49 PM on February 4, 2011

I spent a while working with people who were mostly too poor to buy soap. They weren't piss-covered homeless, just poor subsistence farmers for whom soap was a real luxury. They bathed every day in the river with lots of scrubbing, but soap wasn't an every day item.

It wasn't hard to tell from a few feet away who was using soap and who wasn't, honestly. So yeah, I think our distant ancestors had some strong funk to them, but moderated by splashing around in the water when the weather was warm.
posted by Forktine at 9:17 PM on February 4, 2011

Think about diet as you said. Raw paleo eaters have reported smelling less or different on this diet.
posted by Not Supplied at 3:00 AM on February 5, 2011

Not science by any means, but there's a famous comedy routine from the '70s/'80s by Richard Pryor (which I haven't been able to find on youtube) that hinges on the perceived differences in body oder between African natives and a Western visitor (Pryor). Don't know if it's true or not, but the theme's pretty much that the difference is greater than we'd like to assume, and so would answer your question, yes.
posted by 5Q7 at 10:28 AM on February 5, 2011

My mum tells a story about a guy who would go bush in Bouganville for weeks at a time, eating mostly the local yam. She said he would smell terrible when he got back, even after multiple showers. It would take a few days of eating western food for him to stop smelling horrid.
posted by kjs4 at 6:20 AM on February 6, 2011