The ape that thinks in symbols. A human being.
According to Terrence Deacon in The Symbolic Species, the origin of Homo symbolicus is the point when our cognitive behaviours "became the principal source of selection upon our bodies and brains", i.e. when our physical and mental tools began to reshape us as a better and better tool user.
This encompass both Homo Sapiens and Neanderthal, as well as Homo Habilus and Homo Erectus.
More than any other group of species, hominid's behavioural adaptations have determined the course of their physical evolution rather than vice versa. Stone and symbolic tools, which were initially acquired with the aid of flexible ape-learning abilities, ultimately turned the tables on their users and forced them to adapt to the new niche opened by these technologies.
- Terrence Deacon
So for the last 1 or 2 million years, we have been evolving as nothing but better tool users. We are not animals that suddenly woke up and found themselves suited to consciousness. We have been adapting to tool use, language, culture and thought for a long time. The evidence is on our bodies and brains: The way that children acquire language, the shape of our hands for using tools, our throats and tongues shaped for speaking. Language has co-evolved with consciousness. One without the other would be useless. Language is a tool, so is thought. Our tools shape us.