Sorry about this, but we need to schedule a third Meetup this month to finish the series before Christmas.
The mastery of fire greatly expanded the ecological niche that could be occupied by the carnivorous apes that became us. This also meant that proto-humans had to remember and share larger and more detailed volumes of knowledge about technologies and natural history than had ever been required previously - establishing selection pressures for the cultural construction, sharing and transmission of knowledge.
Before the capacity for linguistic communication was established it is likely that enhanced social behaviors around the campfires such as directed attention, dancing, mime and singing helped with activities such as organizing hunts and sharing critical survival knowledge.
Language would have to be evolved before the details of complex technologies required for making things like effective hunting bows and arrows with hafted heads could be reliably transmitted.
Fire and language gave Homo heidelbergensis the capacity to expand throughout Africa and across Eurasia. A later wave of even more sophisticated Homo sapiens again expanded out of Africa to replace all of the older relations. Arguably, this success was was founded on technological superiority and better systems for managing and sharing knowledge.
