about the monky thery theory

if we evolution  from monkey whay there no others creatures how can talk and think like us "hemo-cat, hemo-dog or hemo-rat" and the sea so big whay there no others creatures how can talk and think like us there.

>>2
So humans evolved particularly large and advanced brains to perform this task.
You have cause and effect backwards there.

You're right about the insane energy cost, though. The fact that there's no immediate payoff for slightly larger brains means that the only way a species is going to develop brains as big as ours is by getting lucky with a sexual selection feedback loop.
It happened for us, and we got lucky in that once you get over the initial hump, high intelligence does turn out to be advantageous. We could just as easily have ended up like the peacock.