I searched some more. In 2013, scientists selected for brain size on guppies and got 9% larger brain in 2 generations. Guppies with larger brains were smarter. This seems to validate feasibility of breeding program and suggests a simple method to select for intelligence.
I searched some more. In 2013, scientists selected for brain size on guppies and got 9% larger brain in 2 generations. Guppies with larger brains were smarter. This seems to validate feasibility of breeding program and suggests a simple method to select for intelligence.
https://www.nationalgeographic.com/science/article/scientists-breed-smarter-fish-but-reveal-the-costs-of-big-brains