Bangladesh is a very populous country that lies almost entirely at sea level, and the Ganga and Brahmaputra flood at least once a year. The problem isn’t not being able to swim in calm water. The best swimmer in the world would still die if he got caught in one of those currents.
Different social animals have different social structures. Wolves generally live in family units, led by the parents. Wasps and gorillas have complicated group politics, with alliances, betrayals and backroom deals. Some primitive ants have a ‘might is right’ system, with the strongest becoming the queen and fighting off challengers. Most ants have a highly democratic system, with decisions made using chemical ‘votes’ (cast by the workers; drones and queens don’t have a say).