Why is the brain, an organ that exists only to make connections, divided? Why is it asymmetrical in so many measurable respects, both structural and functional, and why does its functioning seem to depend on its being asymmetrical? And why is the major connection between the two cerebral hemispheres, the corpus callosum, getting proportionately smaller, and functionally more inhibitory, rather than larger, and functionally more facilitatory, with evolution?
