what evidence besides fossil bones indicates that some very early primates were bipedal?
All we really have to go on are the primates’ bones since those are all that is left. This doesn’t mean we can’t be certain that some early primates were bipedal. By examining the skeletal structure of the fossils and comparing it to that of modern primates (including us) we can determine whether the early primate was physically more suited to a bipedal or quadrupedal life-style.
