I’m usually pretty particular about the sorts of traits that get assigned as humanity’s “special thing” in sci-fi settings, but I have to admit that I have a weakness for settings where the thing humanity is known for is something tiny and seemingly inconsequential that it wouldn’t normally occur to you to think of as a distinctive trait.
Like, maybe we have a reputation as a bunch of freaky nihilists because we’re the only species that naturally has the capacity to be amused by our own misfortune.
Alien: Why are you happy? You’ve been seriously injured!
Human: *struggling to control laughter* Yeah, but I can imagine what that must have looked like from the outside, and it’s pretty hilarious.
Captain XXlr’y: First Officer Jane The Human, your olifactory protuberance is severely damaged! Why is this a matter for mirthful celebration???
First Officer Jane The Human: A SPARKLY LITTLE POMERANIAN THING WITH A GODDAMN UNICORN HORN CHASED ME STRAIGHT INTO A WALL! OH MY GOD! DID YOU SEE THAT? I RAN STRAIGHT INTO THE WALL.
Captain XXlr’y: Yes I just observed this sequence of events! It was terrible!
First Officer Jane The Human: OKAY WHO GOT THAT ON CAMERA, I WANNA SEE.
Captain XXlr’y: So you more fully understand that this is a situation you should never get into again?
First Officer Jane The Human: SO I CAN SEND THE VIDEO TO MY MOM!
Captain XXlr’y: For… for the solicitation of maternal concern…?
First Officer Jane The Human: NO, BECAUSE SHE’LL THINK IT’S HILARIOUS TOO.
Sidetrack but: I am of the opinion that we will be known as the Throwers. The biomechanics of our shoulder joints, which allow us to hurl things farther, faster, and more accurately than any other animal, set us apart almost as much as our intelligence. And indeed our dominance as a species on Earth has a lot to do with applying that intelligence to throwing more better.
When the aliens come visit via seventh dimensional space fold like sensible people, I can only imagine their reaction when we ask them to point out where they come from so we can fling our ambassadors at them.