Supporting evidence for this are feral children who could never learn to integrate into society. They didn’t have built in models of social interaction.
This is just my opinion. I think it took most of your brain to formulate that rebuttal, not concurrently, but as a deep and rich model of how readers might respond to a given argument, and weighing in a narrative sense your remembered experience vs what you "heard" me say in your head when you looked at these squiggly lines. Probably you even had a nascent image of me that was an amalgamation of your past experiences with internet idiots (fairly!) etc.
That's a lot, lot more than what a bug does when it finds its way past a complex maze, and probably something feral children lack.
I think all our higher level "reasoning" is a cooption of these systems.
There's a point in infant development where speech and social skills are developed, after which they cannot be. I'd go so far as to argue you'll never make a mathematician or physicist out of a feral child. Something critical to our higher level thinking is formed then. If missed, it cannot be recovered.
The flip side is I deeply believe if you can hold this conversation with me, then we both can be the best mathematicians there are, if only we took time to develop that language.
So there's an arms race. The more brains you have the more you can model your tribe to know how to help or succeed. AND the bigger everyone's brain is the harder they are to model simply.
In this model consciousness is the "self model" or "self-consciousness" that allows you to model others opinion of yourself by having such an opinion yourself. And adjust their opinion by providing a narrative about yourself which you first have to craft, .... nd on and on with higher levels of abstractions.