Wrong. Did you read the article? Cowbirds raised in contact with only their foster parents (e.g., in captivity) think they are their foster parents' species, learn their songs, and try to mate with members of their host species. This research answers the question of how young cowbirds in the wild avoid this. The answer includes instinctual elements (that drive them to sneak out to meet their biological parents), but learning clearly is an essential factor.
>Did you read the article? [...] , but learning clearly is an essential factor.
I think your reading of the article missed the point of their experiments that dissected the learning :
Yes, the "learning from other-species foster parents" was affecting their non-cowbird type of behavior (e.g. songs).
But no, they did not "learn" the cowbird-specific behavior from any parents. E.g. They figured out their preferred roosting in the fields at age ~20 days on their own.
