Illustration Friday prompt is duet, and I think that Western Grebes perform one of the coolest duets you're ever going to see in nature.
The courtship dance for these birds is very elaborate and involves preening, head-bobbing, and gift-giving. The whole thing culminates in a sprint down the lake, wings tucked back and water churned up by the feet. Eventually they both dive under the water. I'll leave you to look up more information for yourselves if you're interested, but you can watch the particular part of the ritual that I've drawn in this video.
Just as a slightly weird aside... I used to teach music, so you'd think I would have chosen a musical subject for a prompt like duet. I'd think so, too. I have no idea why the grebes came to mind first.