Thanks maeve and MMario. I guessed at the reason but I couldn't find anyone who'd witnessed it. I read Lorentz's books a long time ago. I'd forgotten him. I'll read them again now. Thank you, maeve.
I raise orphaned Australian Magpies each year and sometimes other wild birds but this is my first experience with chickens. I really like birds and relate to them easily. I'm looking forward to getting a few more chooks.
We have a sweet natured rooster who just adores his Big Red Mamma -- Scarlet O'Henna. He likes to share the nest with her and cuddle down under her like a baby chicken. Scarlet's eggs aren't fertile so either he's shooting blanks or he just can't manage to hit the right spot.   
Thanks, Kendall It's fun to have you hang your coat here a while.
Cheers, Joy