The shoulders would combine the humanoid shoulder anatomy, which protrudes out of the body almost like a stalk, with a reptilian position, at the ventrolateral face of the torso. Because of the shape of the body, the shoulders will point downwards, so that the joint is directly under the attachment to the torso

These shoulders would support a pair of legs, similar to the forelegs of lizards

A rough diagram

This may present issues, as the shoulder has more-or-less been rotated, and so there may be issues with proper flexion and extension for walking

Could this anatomy realistically work? Or would the flexibility issues prevent this shoulder from working?

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    $\begingroup$ It's not the first time we ask you to illustrate with a picture what you are asking, right? $\endgroup$
    – L.Dutch
    Commented Jan 7, 2022 at 12:12
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    $\begingroup$ Ape physiology will do fine. Apes and humans are lucky, they have strong arms, flexible shoulders. Apes can do bipedal as well as quadrupedal, humans are weaker already but they can do pushups, although you get endurance problems (of course), and sometimes medical issues arise... google.com/search?q=quadruped+shoulders+upright $\endgroup$
    – Goodies
    Commented Jan 7, 2022 at 12:44
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    $\begingroup$ you should look for malteses, victorians, fron raises records and handstand running..... human shoulders can do a lot of stuff, well considering we are just apes, and apes are just bipedal hairy reptiles, ofcourse our shoulders can support legs, they first evolved to support legs. $\endgroup$
    – Drien RPG
    Commented Jan 7, 2022 at 14:07
  • $\begingroup$ What is a "ventrolateral face"? Pictures would help. $\endgroup$
    – Daron
    Commented Jan 7, 2022 at 20:22
  • $\begingroup$ @Daron -- It's medical talk for "sticking off the body somewhere between directly to the side and directly from the front". $\endgroup$
    – elemtilas
    Commented Jan 8, 2022 at 2:46

1 Answer 1


The problem I see is with the stalked shoulder blades as they would be under immense torque and constantly trying to twist, the shoulder blade is normally situated in such a way that it acts as an anchor to the rib cage allowing for normal movement and the range of motion that we have with the ball and socket joint there the presented anatomy is closer to a hinge joint configuration rather than the necessary ball and socket of a shoulder it would be a very awkward limb being as it were unable to rotate up or down now if the shoulder were to have another piece that joined at the joint you would be able to have an external shoulder as long as the muscles and tendons were able to pull in the right directions, I see no actual reason for any organism to develop such an extended joint as it adds unnecessary complexity and a very obvious weakness that any predator would target to disable the limb as the tendons would be exposed to view, there is a very good reason that this kind of limb has never occurred and probably never will as not only the reasons above apply but also the limb would be far more prone to injury with weight on it applying far more stress due to leverage and injuries that might just dislocate a limb on an ape type body would probably just tear it right off, this is highly impractical and would only really serve as some far fetched science experiment rather than an actually viable creature that could exist in a given environment, the only place I could see this as a possibility would be on low gravity worlds but most likely it would just be outcompeted by other more efficient designs.


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