Why do some people have a tendency to have the same facial features?

April 22, 2004 2:10 PM

Why do some people have a tendency to have the same facial features?
posted by Keyser Soze to Science & Nature (32 answers total)

...the same facial features as what? Other people? Their relatives? Their pets?
posted by nicwolff at 2:21 PM on April 22, 2004

Response by poster: The same facial features in comparison to other homo sapiens, related by family or not.
posted by Keyser Soze at 2:24 PM on April 22, 2004

I'm jetlagged, so maybe it's just me, but --- huh?

The same facial features as WHOM? As themselves? As other people in their family? As other people in the world?

There are only so many variations a face can have before it stops being a face (before laws of physics stop mouths and eyes and ears from working). All the variations within the possible are governed by genes.

So family members (or people of the same race/background/etc.) tend to look somewhat alike.

And it's possible for non-related people to look alike, due to randomness.

Is that what you were asking about? There must be more to your question.
posted by grumblebee at 2:25 PM on April 22, 2004

Okay, like I said. There are only so many ways a facial feature can be. A mouth can be wide, but it can't be six-feet wide, or it won't work.

So even if you rolled dice to determine facial features, you'd wind up with a lot of similarities (given the huge number of people in the world).

And within one family, people pass on features in their genes. I have a big nose because my dad does and his dad did before him. If you don't understand this, I recommend reading some Mendle and Darwin.

There are plenty of other people with big noses who AREN'T directly related to me (though we're all related if you dig deep enough). That's not so surprising when you realize that a nose can only be small, medium or large.

I also have brown curley hair, big eyes and a long face. So how likely is it that someone else has a similar nose, eyes, face and hair as me. It would be ASTOUNDING if many people didn't share these features with me, given the size of the population.
posted by grumblebee at 2:31 PM on April 22, 2004

I know what you're saying, Keyser. Sometimes you see someone on the street who resembles, in one noticeable way, or perhaps several ways, someone else that you know. It's like they're long-lost first cousins from the same long-lost village in Eastern Europe or whatever. Yes. Some people look like Elves. Other people look like The Thing. Other people look like horses. It's not that hard to notice.

It does seem that even if there is infinite variation in the human facial features, that patterns do repeat. I would hazard a guess that this has to do with genes, that the encodings for facial features are less random than we might think, and things like "hook nose" might be true on/off switches and not as infinitely granular in variation as we might suppose.

All that said, I dunno.
posted by scarabic at 2:33 PM on April 22, 2004

Another note: my wife and I always disagree about similarities. She'll say, "don't you think our friend Bill looks JUST like Brad Pitt?" And I'll say, "Huh? He doesn't look ANYTHING like Brad Pitt to me."

I think this is quite common: judging two people as looking alike is HIGHLY subjective, even though it seems objective.

After years of this confusion, I've noticed that my brain tends to focus on mouths. Why doesn't Bill look like Brad Pitt? Beause his mouth isn't the same. But if I cover his mouth, I have to admit my wife is right. So she must not focus on mouths. Perhaps she looks at eyes more.

But this is all rationalization after the fact. My wife gets one really strong gut feeling. I get another.

It would be interesting for you to take two photos of the people you think look alike and do a really deep comparison of the features. How many features are very similar and how many are different? For you, how many features do two people need to share before they "look alike"? Are some freatures more important TO YOU than others?
posted by grumblebee at 2:36 PM on April 22, 2004

Response by poster: What I meant specifically, is how people with no blood relation (directly at least... maybe we are all related by blood) but look the "same". Not exact of course, but like broad shouldered guys with black hair, or thin naturally blond girls with blue eyes and the same cheekbone structure, things like that. I guess I am asking how races are what they are, like did it all come from close knit tribes that didnt fuck outside their people? Are we all a little inbred?
posted by Keyser Soze at 2:38 PM on April 22, 2004

Scarabic, I think this is the normal "illusion" that makes similar events seem profound (fated).

But think about how many people you meet who DON'T look alike.

Keep flipping a coin enough times and eventually you will get ten heads in a row...
posted by grumblebee at 2:39 PM on April 22, 2004

Response by poster: I didn't even think it would be objective. Still, the question remains.
posted by Keyser Soze at 2:42 PM on April 22, 2004

Yes, I think you're exactly right, KS. We're all a little inbred. There are, of course, may mixed-race couples today, but think how revolutionary that is. How many Asians married African Americans a hundred years ago? Even today, don't couples like that stand out in your mind a bit?

I'm a Jew from the midwest who left my hometown and married a waspish girl from the deep south. But for everyone like me -- even today -- how many more people are there who stay in their own neck of the woods and marry locals. Most Africans are married to other Africans. Most Europeans are married to other Europeans. Etc.

It will be interesting to see what people look like a few thousands years, if the "melting pot" trend continues. But I suspect people will always break into factions and stay close with their tribe -- even if the tribes of the future are Microsoft, Google and Sony.
posted by grumblebee at 2:45 PM on April 22, 2004

I have wondered the same thing (I think). One of my husband's little sisters has a totally unrelated best friend who looks exactly like her--their mammas get 'em confused. Even knowing this and remarking at length about it, the similarity is so striking that I still forget, and get spooked out all over again.

Jennifer, how did you change clothes so fast, and without going inside?

I'm not Jennnifer.

Anyway, I wondered if that meant they were related somewhere far up the tree, or if things were just weird that way sometimes.
posted by littlegreenlights at 2:48 PM on April 22, 2004

Well, it's a totally different question if it's subjective:

Objective: why do so many non-related people have similar features?

Subjective: why do those two people look alike to ME?

To answer the first one, you need to learn about genes, geography, and historical movements of peoples.

To answer the second one, you have to explore your own mind. Like I said earlier, I explored mine and realized that no matter how similar two people are, if they have different mouths, they'll look different to me. This wasn't easy for me to learn. I had to really pay attention to the specific features I thought were similar or different.
posted by grumblebee at 2:49 PM on April 22, 2004

I have a theory that all natural redheads are related. It is mindboggling how many redheaded toddlers look like my redheaded daughter did at that age.
posted by konolia at 2:50 PM on April 22, 2004

littlegreenlights, do you ever think of a phrase and then immediately after that someone on TV says that phrase? Why does that happen? Are you and the TV in psychic communication?

Possibly, but more likely it's just a random chance. It SEEMS profound, yet there have been millions of things you thought of that DIDN'T appear on TV. It would be statistically odd if there was never a coincidence.

And I suspect there are more possible things that could be said on TV than there are different facial-features.
posted by grumblebee at 2:54 PM on April 22, 2004

konolia, if you really wanted to spend the time, I think you could test your theory.

All redheads ARE related, because all PEOPLE are related. But I assume you mean that any two redheads must be more CLOSELY related than, say, a redhead and a blonde.

Or you mean that red hair is a trait that only evolved once. (You have to be careful with such reasoning, because some body parts -- such as the eye -- have evolved several times independently!)

It would be interesting to check some historical sources and see if there were mentions of red haired people in two different parts of the world that had no contact with each other.
posted by grumblebee at 2:58 PM on April 22, 2004

You question is fascinating to me. It bewilders me how people are able to distinguish each others' faces at all.

I almost never recognize faces of people I know (even close friends) if I see them in situations where I don't expect them. Once someone says hello, I then spend a few seconds scanning through my mind to look for a match.

For what it's worth, I'm also the only person I know who has lived in Los Angeles for 7 years and has never once spotted a celebrity.

So, I suppose, facial similarity is subjective matter. How close do faces have to be before you consider them to be alike?
posted by 4easypayments at 3:13 PM on April 22, 2004

It's because people actually all look very much alike. We're not as differentiated as we think we are and your question is akin to asking why gorillas' faces tend to look alike. There's only so many ways a face can substantially differentiate from another. Furthermore, some of those ways may be genetically cross-linked which further limits differentiation. (For example, look at hair or eye color.)

The human brain's ability to recognize and differentiate human faces is pretty highly developed and complex and a bunch of different kinds of brain damage can dramatically lower or completely destroy that ability.
posted by Ethereal Bligh at 3:25 PM on April 22, 2004

just read somewhere...can't remember where, but basically, looking at people on a DNA level, humans aren't as diverse as most other species populations...

Also, there is more genetic diversity on the african continent than in the Entire rest of the world combined.
posted by th3ph17 at 3:27 PM on April 22, 2004

Konolia, all readheads are not necessarily genetically related. It's really quite interesting that you would think this as it's deeply related to the biological fallacy of the concept of "race". I often will use hair color as essentially the same sort of thing as skin color to try to explain to people why people with similar skin coloring are not necessarily genetically related. But you, apparently, seem to wonder the same thing about hair color. Do you think this about eye color? How about sex?
posted by Ethereal Bligh at 3:28 PM on April 22, 2004

Keep flipping a coin enough times and eventually you will get ten heads in a row...

Yeah, actually this is sort of what I meant. What I mean is that the "Brad Pitt Mouth" might actually be a distinct gene which is either on or off for a given person. Perhaps there are only 219 nose types in the world if you count them all up. If you've ever played with police sketch artist software you start to see the similarities a bit, and how they can be broken into components. There are indiscrete, on/off genes for lots of things about the body. Perhaps the "Brad Pitt mouth" is one of those, and his nose and eyelashes as well. Like you said, toss the dice enough times, and you're going to come out with a Brad Pitt. This doesn't necessarily mean there will be any traceable relation, but since facial features are hereditary, it's at least possible.

I don't really know what you're talking about anymore, though, Keyser, about people looking completely alike. I do sometimes have the thought "hey - his grandpa must be from the same village as that other guy's" but aside from that I don't know what you mean by inbreeding and looking exactly alike.
posted by scarabic at 4:06 PM on April 22, 2004

It would be interesting to check some historical sources and see if there were mentions of red haired people in two different parts of the world that had no contact with each other.

Sure there are: people with Celtic/Irish ancestry, people with Nordic/Scandinavian ancestry (think "Eric the Red"), people with Khazar ancestry (Turkish tribe, many of whom converted to Judaism in the early Middle Ages, hence the existence of redheaded Jews, like my brother, father, aunt, grandmother, great-grandmother...), etc. It's unlikely that they *all* have the same direct ancestors, unless you're going far enough back in time that all humans are related in a general sense.

What I think you mean, though, is that some genes seem to go together in "packages". Red hair usually goes with fair skin and/or freckles; people generally don't have chocolate brown skin and red hair. Similarly, people don't usually have both epicanthal folds ("Asian eyes") and blue or green eyes. Maybe what you're seeing in people looking "of a certain type" is that you're noticing that they have a number of features/traits that fall into a general type of "package", which may include several interconnected genetic traits. There's a technical term for multiple genes that tend to get inherited together or turn on/be expressed together, but darn it, I can't remember it offhand.

Intermarriage is also breaking apart some of those "packages" in really cool ways: blue-eyed African-Americans (i.e. Vanessa Williams), a half-Chinese/half-Jewish girl I knew in high school with Asian facial features but curly hair, etc. Diversity is neat-o.
posted by Asparagirl at 4:40 PM on April 22, 2004

It will be interesting to see what people look like a few thousands years, if the "melting pot" trend continues.

Time Magazine commissioned a digitally-manipulated photo in the early 1990's of what "the face of America" looked like. They took photos of several women whose facial features, skin color, eye color, hair color, hair texture, etc. were then combined into one "generic American face". The women were of many races and ethnicities and the percentages of their faces that went into the photo was meant to mimic the actual breakdown of the U.S. population: 15% African-American, 70% Caucasian, etc.

The resulting photo looked like a medium-skinned supermodel. One of the surprising side effects of combining a great number of faces into one "averaged" face is that the average of all features from all people is found to be really, really, good-looking.

But dammit, I can't find a link to the article! It's probably from around 1993, when Michael Jackson's "Black or White" video came out and people were thinking about his ground-breaking video morphing sequence at the end.

FYI, the average Russian Internet user faces (one male, one female) are here. Users were asked to use standardized drawing icons to draw pictures of themselves and the results were averaged.
posted by Asparagirl at 4:55 PM on April 22, 2004

I drew caricatures when I was younger. For years I've been trying to start again but I haven't been able to develop it to the degree where I'm capturing the interaction of distortion and resemblance that I'm searching for.

Trying to determine what it is that makes people look the way they do I've spent a lot of time staring a strangers on the bus. Or watching TV chat shows like Charlie Rose where the focus is on the guests' faces. Or downloading pics from Getty Images and looking for the points of character amongst all the different perspectives and expressions. It's still a mystery to me how individuals are so immediately identifiable without being wildly distinct from each other. Most of us stay pretty close to those regular proportions.

Look at someone and you can instantly place them as part of a family or a nationality, but then place those family members side by side and they still look very distinct from each other. We can identify a individual though they are changed markedly by age but can also make the distinctions that allow us to group people by age. Where are the markers that make us similar to those in our various groups and where are the features that allow us to be our own person? Doesn't seem like there's enough possible variation in two eyes, a nose and a mouth for us all to keep our little corner of individuality from the rest of the six billion. But there is.

I've pulled my old Mad Magazines out of my parents' attic and pored over the movie parodies from the late 70s. Mort Drucker was amazing, capturing the likeness of all these different actors through so many expressions and movements, and doing it with a few lines. Look at the take on That's Entertainment and I immediately recognize Gene Kelly, Donald O'Conner although they're just small drawings with limited detail. Look in the background of a movie parody and recognize character actors of 30 years ago. Scatman Crothers in One Flew Over the Cuckoo's Nest; Ray Walston or Harold Gould in The Sting; Abe Vigoda or John Cazale in The Godfather; Charles Grodin, Buck Henry, Vincent Gardenia in Heaven Can Wait. Pick them out instantly, but then puzzle about what he found in that face amongst all the faces to be able to make them so instantly recognizable.
posted by TimTypeZed at 5:44 PM on April 22, 2004

I moved to Japan from the U.S. about 10 years ago. If I spend a few hours downtown, I may come across and view the faces of 1,000 or so mostly-Japanese people, so it would seem almost certain that someone in there would remind me of someone else, even a non-Asian. Occasionally, I say to myself, "He's the Japanese Steve Zuk (my old roommate)" or "She's the Japanese Julie Espy." My wife refers to one of our neighbors as Patrick Swayze because of the shape of his face.
posted by planetkyoto at 6:10 PM on April 22, 2004

Dr. Weston Price, a dentist, has done extensive research on how diet not only affects teeth, but facial structure and general health.

His photographs capture the suffering caused by these foodstuffs — chiefly rampant tooth decay. Even more startling, they show the change in facial development that occurred with modernization. Parents who had changed their diets gave birth to children who no longer exhibited the tribal patterns. Their faces were more narrow, their teeth crowded, their nostrils pinched. These faces do not beam with optimism, like those of their healthy ancestors. The photographs of Dr. Weston Price demonstrate with great clarity that the ëdisplacing foods of modern commerce' do not provide sufficient nutrients to allow the body to reach its full genetic potential — neither the complete development of the bones in the body and the head, nor the fullest expressions of the various systems that allow humankind to function at optimal levels — immune system, nervous system, digestion, and reproduction (Nasty, Brutish, and Short? 8).

The photographs are interesting. And reminds me of a recent comment in a FPP about a certain group of people being characterized as having bad teeth.
posted by Feisty at 7:30 PM on April 22, 2004

I've always secretly thought of the hey-he-looks-just-like-so-and-so people on the subway as God slacking off in the extras department.

And as to gene mixing, (and in re the Time photo) I'm often struck by how attractive mixed race people tend to almost universally be.
posted by CunningLinguist at 7:31 PM on April 22, 2004

I think grumblebee's comments on the interpretive side of this are relevant. Perhaps there is infinite variation in facial structures, but our brains were built to break down and lump together certain feature types.

When I first meet someone I sometimes think to myself "they look like Celebrity X" and afterward, once I've gone home, I can't recall their face for the life of me. All I get is Celebrity X.

In other words: people don't look alike. It's in the eye of the beholder.
posted by scarabic at 8:02 PM on April 22, 2004

One of the William Gibson novels has a criminal-identification system which is based on what celebrity people remind you of. As in "he was kind of a Patrick Swayze, with Bill Gates' chin".
Makes sense to me.
posted by signal at 6:52 AM on April 23, 2004

And as to gene mixing, (and in re the Time photo) I'm often struck by how attractive mixed race people tend to almost universally be.

The fashion world has noticed, too: the percentage of mixed-race models and supermodels is much higher than their general representation in the world. Even models who may "read" as Caucasian are often mixed-race to some degree: witness the huge number of stunning supermodels from Brazil, a country with a long history of many gradations and mixtures and admixtures of different cultures/ethnicities (native peoples, Portuguese, Spanish, German, African, etc.).
posted by Asparagirl at 10:45 AM on April 23, 2004

keyser - It's been shown through genetic tracing, I've recently read (probably on the BBC), that almost all European DNA (but for the genetic influx from non-European invading armies contributions - randy Mongol horsemen, etc) comes from a VERY small initial founder group of a couple of hundred at most and maybe as few as a two dozen. (I hope I got this more or less right. I think so...)

So - if you're talking Europeans......we're all inbred, just like in "Deliverance"! *plays Banjo riff*

Also, there are those "Morphogenic Fields"......woo woo woo.....not.

asparagirl - My Jewish grandmother-in-law, before she lost her mind, made a comment about my Uncle-In-Law's beautiful mixed Jew/Goy children who seemed to have escaped all the genetic quirks of my in-law Jewish family line (scoliosis, for one, and lots of moles).

She said something along the lines of "You really need a little outbreeding once in a while." But I can't recall clearly, alas, whether or not she then made some comparisons to the breeding of farm animals. Regardless, it made sense to me.

I suspect the "tiny initial founding group" problem is one that actual plagues many population groups. Ashkenazi Jews may have more genetic problems than usual, I suspect, but I wonder also about many other big groups that were semi-isolated for long periods of time......(fill in blanks, please)
posted by troutfishing at 2:09 PM on April 23, 2004

My Jewish grandmother-in-law, before she lost her mind...

Wow, the number of times I've used that very same phrase! too good to pass up, sorry!

a VERY small initial founder group of a couple of hundred at most and maybe as few as a two dozen

Among men, yes, there are maybe a few hundred European haplotypes for Y chromosomes. Among both women and men, there are (in general) only about seven haplotypes for mitochrondrial DNA (mtDNA has a much slower and less frequent mutation rate than regular DNA and is only passed mother-to-child). See the book The Seven Daughters of Eve by Bryan Sykes for more info.

Being a genealogy buff whose research has pretty much hit a brick wall, I actually went and had mine tested with a company operating online, FamilyTreeDNA.com, and wrote about the experience on my blog (self-link!). Apparently, my most-distant maternal ancestress was a Scot (!) living between 750 A.D. and 1350 A.D., which explains why I'm haplogroup H and not J. So somewhere back in the further branches of my tree, there was some mixed-race nookie going on. Not much recently, though, unless you count my marrying a swarthy half-Sephardic hottie, and that's still playing the field rather close to home.
posted by Asparagirl at 4:16 PM on April 23, 2004

Shiny flash face building toy
posted by mbd1mbd1 at 7:02 PM on April 23, 2004