>>149560430While there isn't necessarily big sexual dimorphism in ducks, besides plumage, male ducks do tend to be slighter stronger than female ducks, and in some species slighter bigger.
Unlike in some birds they also don't take turns nesting the eggs, so I could see a similar provider role for males spring up, while the females take care of the eggs.
After that it would probably take on a different form compared to humans, since males rarely stick around to take care of the ducklings.
Since ducks also have more of a type r-selection strategy, where they have many offspring with less investment, compared to human type k-investment, with few offspring but large investment, they'd likely have a different family system, and subsequently social system in place, likely having a bigger focus on individuals compared to social groups.
Honestly, they'd probably be pretty shitty people to be around from a human point of view.