Do other species exhibit facial dimorphism between sexes?

Between humans, one can generally tell the sex of an individual just by looking at their face, even with the hair and facial accessories removed.

Do other animals have this trait too? If humans can’t readily tell, can statistics or computers make that determination by analyzing facial features or their placement?

I think the OP exhibits a bit of species-centric bias by focusing on the face. If we did not wear clothing gender could often be discerned in other body parts, and I don’t meant just the genitals. Muscularity of legs and arms, for example. Even total body size.

With that, it is easy to point out that there are many ways for humans to distinguish the gendrrs of other species. The most obvious in my mind is how among many birds, the males have brighter colors than the females.

Removing hair and facial accessories (whatever those are) makes it a lot harder. But yes, male cats have a different facial shape than female cats.

Well, yes, on purpose.

Not if they were neutered prior to going through cat puberty.

In many animals in which there is significant sexual dimorphism, it would be fairly easy to tell males from females by looking at the face. As in humans, males often have larger and more prominent features. We aren’t so much aware of this because we don’t spend as much time with other species as we do our own. Of course, in many species sexual dimorphism is much more extreme than it is in humans and it is easy to differentiate between males and females at a glance.

Male proboscis monkey.
Female proboscis monkey.

Male gorilla.
Female gorilla.

Male African buffalo
Female African buffalo

Rather irrelevant to the OP, since that’s not a natural condition.

Could someone give a link to a something with evidence that there is sexual dimorphism in faces in humans? I’ve never heard this before. It very well might be true, but I’d like to see the evidence.

Seriously? Are you saying you can’t distinguish male and female faces? Look around you. Most people can quite easily distinguish most male from most female faces independently of other cues. This is true regardless of the race of the individuals. Speaking as a biologist, I would think this is so blatantly obvious that it requires no cite. But for the record, here’s one of many:

An analysis of sexual dimorphism in the human face.

Lots of things that some people think are obvious are also wrong. It wasn’t obvious to me that it’s true. Telling me that there must be something wrong with me because I don’t see it doesn’t help to convince me. It just comes across to me as saying, “We’re going to make fun of you for not agreeing with us, since that’s easier than showing you evidence.” A paper laying out the evidence does help convince me. Thank you for the link.

Hey Wendell, I find this really fascinating. Would you be willing to take a quick (10 ish minutes?) test on facial recognition with hair and facial hair removed? There are children and adults. Can you easily tell who’s male and who’s not?

Edit: Duh, a link might help:

I mean things like obviously feminine earrings, lipstick, etc.

Really?! I never knew that. How are they different?

Orang Utan faces

Adult male cats have a broader jaw and a longer, kind of a more rectangular face. Female cats have a rounder or more triangular face. In most breeds the males are larger all over including their heads–in some breeds, less so.

I think we’re missing something important here. The fact that we humans find male and female faces easy to distinguish is not solely a property of the faces. It is also a property of our own dedicated facial-recognition software (as referenced in the face-blindness test above). I’m sure cats would find male and female humans as difficult to separate out as we do male and female cats. Objectively, animals like the proboscis monkey show much more dimorphism in the face than we do - our differences are pretty subtle.

The head and face of a male wild turkey is quite noticeably different from that of the hen.

Yep, hence the part about needing computers or fancy math to calculate the differences – our facial recognition isn’t built for that, but presumably theirs is and we can perhaps emulate it artificially.

So are you in essence asking

“do most animals have a similar/greater degree of difference in male versus female features than humans do?”


“do most animals have the ability to distinguish male versus female by looking at the faces alone?”

Because I imagine a lot of animals would have much less need for the latter, specifically, than humans do. Any animal that goes into heat, for instance - all their sexual recognition can be done by smell.

The former.

Just like in humans, facial recognition isn’t necessary or even important for sex identification at a distance. But it’s interesting nonetheless.

I just wanted to know what other animals exhibit similar differences in their faces, and this thread has a lot of fascinating answers so far. I never knew it was at all present in the animal world!

This link may interest you (NSFW: not porn but some people in the nude):
It is not a scientific article, but it is an article aimed to inform about feminisation surgery for trans women, scroll down to “skull and face”.

There is a whole industry around that because one of the things that screams “male” to people (for caucasians at least), is a big brow ridge and a strong jaw, for ex. For some women, trans or not, this can mean being routinely taken as a guy even with plenty of other female physical characteristics.

If you scroll down to “Examples of FFS”, you’ll see before/after pics of trans women who had a variety of facial feminisation surgeries. I’m sure a google search would bring out more.

As far as animals go, I’m able to usually tell if a dog is male or female just from the head/neck. Males are usually more bulky, with a broader face, stronger facial structures, and in some breeds this is even more obvious. (most dogs aren’t neutered in France)