this is very interesting feedback. We have 11 chicks, about 10 weeks and 6 guineas, about 7 weeks. We were keeping them together in the coop but have moved the guineas into a pen at night with free ranging starting today. The chicks are not that much bigger but they still beat up on the guineas. We plan on moving the guinea pen to the front orchard while the chickens stay in the backyard, either in a run and coop or free range and coop at night. The posted info has reinforced my idea to separate their "territories".