Somehow we drifted away from evaluating evolution to Marxist theory. Evolution doesn’t have to be uniform. Some dinosaurs still existed during the mammal era and even live today. This doesn’t mean we live in a dinosaur era. Sure, some limited number of people still live in hunting and gathering societal formation somewhere in the depth of Amazon, etc. However, their number is negligent compared to the entire earth population. The most of the planet still lives in the transitional period between feudalism and capitalism and a relatively small number of a population live in more advanced societal formations.

As for Marxist theory – the only implementation of this theory existed in Israeli Kibbutz and in similar small communities around the world in the 19h century. Whatever happen in Russian, China and Cuba was not Marxism, but let’s call it Leninism or Stalinism, which are far away from Marxism.