You must log in or register to comment.

Notorious_Rug t1_iwp24a0 wrote

Gorillas use columnar knucke-walking, where the wrist and hand joints are aligned in a relatively neutral, straight position, which helps with weight bearing. Gorillas are not as arboreal (tree-dwelling) as chimpanzees, so their form of knuckle-walking evolved to maximize terrestrial movement, as well as the aformentioned weight-bearing.

Chimpanzees knuckle-walk with extended wrists, which is due to the fact that they, like most primates, extend their wrists to preserve their balance while engaging in arboreal activities. Due to this need to extend their wrists to preserve balance and protect themselves in an uncontrollable fall, the chimpanzee's wrist bone anatomy has evolved to differ from that of a gorilla, which results in a different form of knuckle-walking.


mynamecaligula t1_iwpfr85 wrote

how are you so wise in the ways of the monkey?


jaxxxtraw t1_iwpjltv wrote

That's the Notorious Rug, do you even need to ask?


factfarmer t1_iwpzxir wrote

Notorious rug?


Graekaris t1_iwq2u63 wrote

You haven't heard of him? He's notorious.


factfarmer t1_iwqfh11 wrote

Apparently I’m out of the loop. I only know about the notorious B.I.G. and R.B.G.


Similar_Radish8623 t1_iwqqmtm wrote

Ruggie Ruggie Ruggie, can’t you see: sometimes your facts just hypnotize me


Jaksmack t1_iwqvz14 wrote

I just love the things you say,

guess that's why you're smart about primate ways..


dmnhntr86 t1_iwq04a6 wrote

Facetious use of "monkey"?


Ameisen t1_iwrcnq9 wrote

Apes are monkeys - they're a clade within the catarrhine monkeys. A fairly deeply-originating one at that.

There's no way to define monkeys with apes not being included without being quite paraphyletic.


webbphillips t1_iwrvcup wrote

Cool! Does this also mean that all of us mammals are actually mammal-like reptiles?


Ameisen t1_iwsbdu8 wrote

Reptiles are diapsids, while mammals are synapsids. Though it depends on your definition of "reptile", though when amniotes first appeared they very rapidly split into synapsids and diapsids, while apes appeared 10 million years after the first Cattarhines (and aren't significantly different from their closest non-ape relatives).


kfederal t1_iwsla13 wrote

Can I pay you to spit evolutionary facts by my bedside while I fall asleep?


Ameisen t1_iwsnowq wrote

All the mitochondria in all Eukaryotes are the descendents of a single proto-mitochondrion (likely closely-related to Rickettsoid bacteria) which was engulfed by an early proto-Eukaryotic cell, but was not destroyed.


fallingcave t1_iwp2yrw wrote

Thank you monkey man


DellSalami t1_iwpir37 wrote

So if I’m understanding this right, gorillas knuckle-walk with their hands balled up in fists, while chimps have their palms flat(ish) on the ground?


LemursRideBigWheels t1_iwpk1mz wrote

Think a vertical orientation of the hand vs a more canted orientation of the hand. Neither ball their hand up or place their palm on the ground while locomoting — they use the middle set of knuckles for support. Interestingly, what you describe is somewhat akin to what’s seen with orangutans when on the ground or arboreal monkeys respectively.


Beret_of_Poodle t1_iwptwyj wrote

Gorillas use their arms to support their weight. They are extremely top heavy. Chimps use them for balance


DorisCrockford t1_iwqf4wl wrote

I understood it as saying the chimps' wrists are bent while the gorillas' wrists are straight.


CeaRhan t1_iwrfc57 wrote

The gorillas keep their hands/wrists straight to do something similar to what our legs do/look like while doing it, because they're essentially using them as front legs and they need to make sure they won't break/damage their wrists. So they essentially do the second picture here and put their knuckles on the ground.


Norwester77 t1_iwt1d2v wrote

No, both species knuckle-walk with the hands curled and the middle bones of the fingers on the ground. Chimps knuckle-walk with their wrists bent, but gorillas knuckle-walk with their wrists straight.


xDaBaDee t1_iwpj52p wrote

I am going to add my two coffee cup cents to this user's oh so very words on wise. I would think weight and size would affect this.

I would also suggest OP check out, if interested in the same topic, the info on horse movement. I watched one that explained and showed how when horses run there is a moment when all four hooves are not touching the ground. It was interestingly informative. Now back to my regular coffee cup consumption.


Ainothefinn t1_iwpjmb7 wrote

That's true, but not for all of horse running. Horses have varying gaits and only in a gallop are all four feet off the ground at the same time.


merrycat t1_iwpvn42 wrote

I was really surprised to find that moment of suspension wasn't when the legs were all outstretched, but when they were gathered under the horse, just before the hind legs touch down.

Some dogs have a double suspension gallop which is more what Iwas expecting. All four legs are off the ground when gathered under them, and again when they're all stretched out.


Tiny_Rat t1_iwqabou wrote

The dogs that run like this have much more flexible spines than horses, and are also much lighter for their height. A horse doesn't have enough flexibility and power to run like that.


natx37 t1_iwpjzdm wrote

The running movement is defined by a moment when all legs are off the ground for all species that run.


SpiceySlade t1_iwq1utx wrote

You might want to try consuming the coffee instead of the cup. I expect it'll result in less mouth injuries.


sharaq t1_iwpm15q wrote

Why would it surprise you that all four legs do not touch the ground? That's how everything runs. Even the running emoji features someone at that moment in their stride.


factfarmer t1_iwq08en wrote

Not really, even horses. With most gaits, only two feet off the ground at a time.


sharaq t1_iwqel7h wrote

>with most gaits

Yes, and with most gaits, a human likewise maintains contact with the ground, but those gaits are not a "run" or appropriate equivalent (gallop).


Snarlio t1_iwr1yja wrote

I think it's also worth noting that the clavicle (collar bone) of arboreal apes is different than that of terrestrial apes. Gorillas have a more "C" shaped collar bone, which allows for a lot more force to be applied to the sternum and rib cage without the bone breaking. This lets them put a lot more weight on their arms safely.

Chimpanzees have an "S" shaped clavicle, which is not nearly as efficient in transferring force, but allows for a lot more mobility for brachiation (swinging through trees). It's the same reason that people can break their collarbones when they fall face first and use an outstretched arm to break their fall - we also have "S" shaped clavicles.

Found this after a quick search: Figure 2 shows the bones in question


FillRevolutionary900 t1_iwr5n7n wrote

But then humans are terrestrial apes, not arboreal apes. So why do we have S shaped clavicles like chimpanzees?


waterslidelobbyist t1_iwr9rvz wrote

We share a common ancestor with chimpanzees more recently than with gorillas. Either the mutation to a more gorilla-like clavicle hadn't happened or was not enough of an advantage to be selected for as we evolved away from proto-chimps.


FillRevolutionary900 t1_iwrab2v wrote

But that makes the statement distinguishing the terrestrial apes and arboreal apes in terms of the shape of their clavicles meaningless. Because there are really only two terrestrial apes (gorillas and humans), and one of those two doesn't fit what the statement claims. So why make that distinction in the first place.


waterslidelobbyist t1_iwrkjyx wrote

I'm honestly not smart enough to explain the distinction but I'll try. We're one of the two terrestrial apes now, but in the Miocene we've got a whole grip of weird apes running around Africa and Eurasia on the ground, and they're all more closely related to gorillas and have similar adaptations.


Norwester77 t1_iwt0whv wrote

We don’t seem to have gone through a knuckle-walking stage (the ancestors of gorillas, chimps, and humans became terrestrial independently of one another), so our clavicles never had to support much body weight.


vooyyy t1_iwqdam0 wrote

Can you explain more about the anatomical wrist differences?


MrInfinitumEnd t1_iwst5pd wrote

>extend their wrists

What? What does this even mean?

>which is due to the fact that they, like most primates, extend their wrists to preserve their balance

the 'extend their wrists' here is unnecessary and doesn't make sense.

'which is due to the fact that they want to preserve their balance' is better.


Norwester77 t1_iwt0bd0 wrote

Extend the wrist = bend the back of your hand toward the back of your forearm.

Flex the wrist = bend the palm of your hand toward the underside of your forearm.


outboxtheside t1_iwpdmss wrote

From a study comparing the genus Pan (chimpanzees and bonobos) with the genus Gorilla:

If you're looking for a visual.


bwyer t1_iwpyknb wrote

Thank you.

Of course, I was promptly forced to recreate the position with my own hands to really figure out what was going on. The diagrams were quite helpful.


sticksnstone t1_iwq21z0 wrote

So the "arm" of the gorilla is stiff while that of the chimp is bent at a joint.


mtx013 t1_iwqa2bs wrote

Thats not an arm, the image shows a profile picture of wrist/hand/fingers, but your point stands.

For reference, use your own anatomy: the bone they use to touch the ground is the middle bone of your fingers (thumb excluded) and the finger tip is curled up. From there we have the finger first bone (slightly bent), hand bone (big one), two wrist bones and just the end end of forearm bone.

The main difference between the two species is how the forearm-wrist, wrist-wrist and wrist-hand articulations are used. Chips bend them and gorillas use then in a straight line.


wi_voter t1_iwrz4uv wrote

I have to jump in with an FYI. The reason humans do not have to knuckle walk is because our pelvic bones are oriented more in the frontal plane while other primates have their pelvic bones oriented more in the sagittal plane. Our frontal plane orientation allows us to successfully stand on one foot when the hip abductor muscles contract on one side and keep the pelvis from falling on the other side like a seesaw.

Jumping in because years ago in college I got to assist in the research on the hip abductor muscles and their role in unilateral stance and gait. This was always one of my favorite little factoids from those days. :)


updn t1_iwsa8tm wrote

It seems pretty well established that humans evolved to be runners. I can almost visualize the transition to a more upright stance and balance as we get into more of a gallop


junegoesaround5689 t1_iwt1e65 wrote

The upright stance developed more than a million years before adaptations for long distance running. The running adaptations happened around the homo erectus timeframe ca 2 million years ago. The bipedal/upright adaptations occurred in the ardipithecus to australopithecus timeframe ca 4.5 to 3 million years ago with some going back even further.


[deleted] OP t1_iwppj17 wrote



genesis-terminus t1_iwptw2u wrote

Not the scientific answer we needed, but quite pleased with the comedic support you’ve provided. Carry on, good sir.


Fayko t1_iwsfbic wrote

Gorillas are built to be more thicc and walk more with them baby bearing hips than their fingies.

Chimpanzees have had spinal issues for so long they got chineese grandma backs so gotta shuffle their weight more to their back and hands.


Key-Seaworthiness764 t1_iwqq75l wrote

Lemursride is correct with the middle knuckles. Like a karate chop but you curl just your fingers in half. That is the difference between the two' walking with knuckles though both can, and do use both technique' if motion dictates it.


[deleted] OP t1_iwp2vp1 wrote