One of those moths is this guy, who (in flight, not so much in still images) looks and sounds like a miniature hummingbird: https://en.wikipedia.org/wiki/Hummingbird_hawk-moth
I noticed these for the first time earlier this summer. Incredible insects! They really do give a hummingbird impression.
rare instance where the German name Taubenschwänzchen ('little dove-tail') is nicer than the English name
Very common around my mom's house.
For many people, it is the other way around. It is very remarkable that there is a bird, which looks so much like a big version of this butterfly!
After all, in Europe these butterflies are commonplace, but I've never seen the American bird in my life.