Today, I was thinking about a few species I've designed, and I realized that while I had some quite fleshed-out ideas about their cultural values, language, rituals, history, and biology, my vision for them was sorely lacking in terms of what everyday, friendly communication would look like--small talk, if you will. I've come up with insults, honorifics, ranks and stations, terms of endearment and deference, but it's all so terribly serious: excellent for dramatic standoffs and climatic set pieces, but not very applicable for the more mundane situations that would form the bulk of any real people's lives. As it stands, my people feel decidedly like a severe, monolithic fantasy race, and lack a sense of relatableness or tangibility. A critical element of lightheartedness is missing.
The element that I think is most sorely absent from my species is humor. I have no idea what my species laughs about, how they demonstrate wit, or how they keep each other amused on long hunts in the desert (or long nights in the cybernetics lab, as the case may be). I can imagine them enthralling an audience with tales of glory and bloodshed, or reciting myths of ancient warriors and vengeful spirits, but I draw a blank when trying to picture them laughing around a fire and think about what they're laughing about. And I think it really diminishes the "fullness" of their conceptualization.
There are several different species I'm thinking about, so rather than go into specifics for each one right away, in this question I'd like to address the wider issue of designing a sense of humor for a species. I know that humor is a notoriously subjective phenomenon among humans; indeed, the fact that ideas of what is and is not funny varies so wildly between cultures and individuals is a large part of what inspired this question.
So, on to the meat of what I'm asking:
Are there aspects of humor that are universal or nearly universal among humans that we would expect to arise in other sapient species? Or is literally anything fair game?
What cultural, linguistic, historical, or biological factors can influence a species' sense of humor? Or do these things have no effect?
Assuming a non-human sense of humor might would probably not be funny to most humans, how can I make a sense of humor be convincing for the species even if it's not funny to us?
Can a culture have no sense of humor? If so, what other types of interactions might take its place as a lighthearted social glue?