A 2008 study published in the open access journal Genome Biology suggests that during our evolution, we reached a point where our brain met the limit of its cognitive capabilities. To overcome this, the organ evolved rapidly in order to increase the rate at which it performed metabolic processes. Certain psychiatric conditions, such as schizophrenia, are a byproduct of these dramatic molecular changes, one prominent theory states.
https://bigthink.com/philip-perry/sc...plex-evolution



@Dalek, yes right! even major mental illnesses can be just a natural product of evolution... what looks like a disease might actually be a collective boon to the future.