Increase in cranial capacity is regarded as the most significant change as it leads to the expan­sion in the cere­bel­lum and neo­cor­tex, areas which are asso­ci­at­ed with learn­ing, con­scious thought and reasoning. The devel­op­ment of the brain enabled hominids to make and use tools and fire, com­mu­ni­cate using lan­guage, devel­op cul­ture and soci­ety, adapt to new envi­ron­ments and, final­ly, to become self-aware and creative.