I suspect both language-use and upright-posture have anatomical consequences. So does the fossil record show which came first?
NOTE: To the folks who marked this question "homework": This is certainly not an actual homework question. I have been an accomplished biologist for over 30 years and I am genuinely interested in the evidence for the timing of these critical human attributes. If you feel that the answer is so trivially obvious, that I should have been able to find out with only modest research, could you please leave a comment explaining, as if to a child, exactly how it is so obvious?