(September 27, 2017 at 9:58 am)FatAndFaithless Wrote: I'm not sure exactly what you mean by 'humans cannot evolve'. We are evolving. Every organism is, all the time. It might be hard to comprehend because our human timescales are less than a blink compared to the scales on which evolution works, but changes in allele frequency over time is absolutely happening in humans - and with enough time these changes in allele frequency leads to speciation.
Absolutely, better to look at overall primate evolution to understand the scale of change that can occur over time.