I couldn't help but notice that some of the swimmers in these Games have extraordinarily long necks:
Aliaksandra Herasimenia, the silver medalist in the 2012 Olympics in the 50 and 100 freestyles, and silver medalist in Rio in the 50 free:
Penny Oleksiak, the 16-year-old silver medalist in the 100 fly and gold medalist in the 100 free (on right):
Kevin Cordes, a finalist in both the 100 and 200 breaststroke:
I have no idea whether a long neck is an advantage in swimming, and if so, how that advantage would work. But it seems more than just coincidence that some of the better swimmers are a little swanlike.