A few weeks ago when I was out cycling with some friends, we saw a few birds who looked like they were sleeping. Someone asked me what they were doing, and I said they were resting or sleeping but I'd ...

Editor’s note: This story was originally published in February 2018. Free time is dangerous for me. I ponder imponderable questions, like “Do birds sleep?” Well, yes, but not the same way we do, and ...

Some birds possess a remarkable ability to sleep with one brain hemisphere awake. This adaptation allows them to remain vigilant for predators and fly long distances. Ducks and swifts are among the ...