Apparently, design is okay if microbes do it:
It seems so obvious that someone should have thought of it decades ago: Since parasites have plagued eukaryotic life for millions of years, their prevalence likely affected evolution. Psychologist Marco Del Giudice of the University of New Mexico is not the first researcher to suggest that the evolution of the human brain could have been influenced by parasites that manipulate host behavior. But tired of waiting for neurologists to pick up the ball and run with it, he has published a paper in the Quarterly Review of Biology that suggests four categories of adaptive host countermeasures against brain-manipulating parasites and the likely evolutionary responses of the parasites themselves. The idea has implications across a host of fields, and may explain human psychology, functional brain network structure, and the frustratingly variable effects of psychopharmaceuticals.Christopher Packham, “Did parasite manipulation influence human neurological evolution?” at Phys.org
Paper: Marco Del Giudice. Invisible Designers: Brain Evolution Through the Lens of Parasite Manipulation, The Quarterly Review of Biology (2019). DOI: 10.1086/705038 (open access) Follow UD News at Twitter!
See also: Eating fat, not meat, led to bigger human type brains, say researchers. Theories of the evolution of the human brain are a war of trivial explanations that no one dare admit are too trivial for what they purport to explain. It’s like blaming World War II on indigestion, only monstrously bigger.
Earlier discussion of the fat theory.
Starchy food may have aided human brain development
Do big brains matter to human intelligence?
Human evolution: The war of trivial explanations
What great physicists have said about immateriality and consciousness