Complex sentence: Morgan's work is now usually regarded as outdated, and there is no universally accepted description of the way of life of pre-historic humans; however, there are many advocates of the notion of primitive communism, both Marxist and non-Marxist.
Split into simpler sentences: Morgan's work is now usually regarded as outdated, and there is no universally accepted description of the way of life of pre-historic humans. However, there are many advocates of the notion of primitive communism, both Marxist and non-Marxist.