Humorless Aliens

"Humor. It is a difficult concept."

—Lt. Saavik, Star Trek II the Wrath of Khan

For better or for worse, humor is one of the most common communicative tools of the human race, and more than anything else it unites us. It is understandable, then, that alien visitors to Earth might find it difficult to understand our attempts at jokes. In popular media this often translates into extraterrestrials appearing to be Sarcasm Blind or to have No Sense of Humor. Sometimes these aliens know what humor means, but don't know or understand why a human joke is considered funny due to cultural differences and the like. An extreme variation makes the alien sense of humor impenetrable to the human mind.

Compare Creative Sterility.

Examples of Humorless Aliens include:

Anime and Manga

Kyuubey from Puella Magi Madoka Magica doesn't understand humor, as well as the rest of human emotions.

Comic Books

The Guardians of the Universe from the Green Lantern comics don't have much of a sense of humor. It's not usually made a point of, but there is the end of "In Blackest Night", a story by Alan Moore from Tales of the Green Lantern Corps:

...and four cycles later, in the recreation complex, Katma Tui realized that for the first time in many years' service, she had heard a Guardian make a joke. She felt vaguely uneasy for the rest of that day.

- There's a reason for this, though: The Guardians believe that emotions lead to downfall.
The Justice League of America story "The Tornado's Path" is about Red Tornado, an android body animated by an air elemental. His wife says that the way she always knew he wasn't Just a Machine is that he has a sense of humor. It's presented well... but then spoiled when the counter-example given of humorless robots is the Metal Men. Seriously? They're the goofiest bunch of robots in the DCU!

Film

The aliens in Galaxy Quest don't seem to have a sense of humor, until the very end.

Literature

Andalites in the Animorphs series do not understand humor or its purpose, though Ax seems to get better at it as the series progresses.
In Mass Effect: Retribution, David Anderson, while having lunch with the Elcor ambassador, Calyn, jokes about attacking Din Korlak (Calyn's office mate, about whom he had been complaining) and "watching the butterball roll out the door". Calyn finds this joke disturbing, and notes that he's unsettled by humanity's sense of humour.
- Fridge Brilliance: The Elcor are heavyworlders, evolving on a planet where the high gravity means a simple tumble can cause serious injury or death. Naturally, jokes based on the subject of knocking people over or throwing them around hit their Dude, Not Funny button—it's not so much the case that Calyn is a humorless alien so much as Anderson sounds like he thinks hurting people is funny.
- The Turians struggle with the concept of humor as well, with Turians like Garrus (who has a fairly well developed sense of humor) being the exception instead of the rule.
Most of the ETs in David Brin's Uplift novels have no sense of humor. The Thenannin in particular are famous for this (so much so that the shocking climax to one of the books is a Thennanin laughing). On the other hand, the Tymbrimi have if anything too much of a sense of humor - that's why they like us so much!
Averted in a classic short story about unintentional First Contact between a human interstellar mapping ship and their alien counterparts. There's a lot of tension about whether the two species will ever be able to trust each other, but the comm officer is not worried. He explains that he's pretty sure we'll be able to overcome our differences, because he and his alien counterpart spent the last hour before both ships left swapping dirty jokes that they both found hilarious.

Live Action TV

Averted in Babylon 5, where alien characters occasionally tell each other lightbulb and knock-knock jokes they've probably heard from humans. Also, it's stated that Minbari humor differs from Earth humor in that it is based on failure to attain spiritual enlightenment.

Of course, there is the episode where Londo Mollari fails to appreciate Rebo and Zooty's humor, but it is unclear if this is a matter of cultural difference or is simply just Mollari. Likewise, Sheridan completely fails to understand a Minbari joke that cracks Delenn up.

This trope is referenced many times in-universe in The Big Bang Theory when people call Sheldon an alien, ask what planet he's from, etc.
On Mork and Mindy, Mork has a hard time with the concept of humor.

Oh, humor! HA! HA!

In Stargate SG-1, O'Neill is distrustful of the Ashen for precisely this reason. Also, Teal'c tends to miss the point of O'Neill's jokes. Funnily enough, the trope is also inverted in one episode; Teal'c, with prompting, tells a Jaffa joke that obviously amuses him, but falls flat on its face with the rest of SG-1.
In Star Trek:
- Vulcans are said to have no sense of humor, but are indeed a race filled with Deadpan Snarkers.
- Data from Star Trek: The Next Generation, while not technically an alien, repeatedly attempts to understand humor as part of his quest to become more human. He doesn't succeed until he gets his emotion chip, which is one of the plot threads in the movie Star Trek Generations.

Video Games

In Mass Effect:
- The turians are seen as "uptight" by most other species in the galaxy. They're basically by-the-book Space Romans that take duty and protocol extremely seriously. This was one of the reasons why the turians were one of the worst possible ways for humanity to become introduced to Citadel Space. Since then, however, humans and turians get along better, and because Mass Effect likes to subvert Planet of Hats so much, it's been shown time and again that individual turians are more than capable of being funny. Your token turian teammate is even a Deadpan Snarker!
  - Hell, in Mass Effect 3, said teammate and your Ace Pilot pass the time by exchanging politically incorrect Human/Turian jokes.
- The elcor can also count as an example. Because of their severe monotone, it's had to tell when they're being funny. It's likewise hard for other races to tell.
- The geth. They're a Mind Hive machine race, so it makes sense.

Western Animation

In one US Acres segment on Garfield and Friends, aliens have come to steal Earths' sense of humor, since humor is a lethal weapon to them.
In Justice League, Martian Manhunter seems to respond to Flash's attempts at humor with either confusion or disdain.
Starfire in the Teen Titans cartoon has some trouble understanding why, exactly, Beast Boy's jokes are supposed to be funny. When exposed to "Why are ducks so funny? Because they're always quacking jokes!", she said something like, "Oh, I get it! It is humorous because ducks lack the large brains necessary for the telling of jokes!"

Real Life

This can be Truth in Television amongst humans. Lots of joke are hard to translate across cultural barriers, and even within a culture humor tends to be subjective.