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.
Snarlio t1_iwr1yja wrote
Reply to comment by Notorious_Rug in I saw in a video that chimpanzees and gorillas do not knuckle-walk in the same way, but they didn't explain what the difference is. Could someone elaborate on the physiological/anatomical differences? by [deleted]
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: https://doi.org/10.1002/ar.a.20354 Figure 2 shows the bones in question