jak86094 wrote:
I read recently that Brown-headed Cowbirds developed their brood parasitism because they followed the bison herds in the American prairie. Since the bison herds migrated across the prairie, the cowbirds would lay their eggs in other birds' nests and continue following the bison, leaving their young to be raised by the stable species that did not leave with the bison. The young join the adults following the bison herds as they mature. jak
Interesting, plausible, possible.
Tks for posting.