Much like the genetic blueprints given to each of us at conception, blueprints for pumping blood, exchanging carbon dioxide for oxygen, digesting food, eliminating food, and retaining memories, we come with a built-in sense of humor. Could our sense of humor have evolved, meaning come about by millions of tiny, modifying, successive steps over millions of years? Or, did it arrive in one lump sum, by design? There are good reasons to suspect the latter.  But first some background musings.

For one thing, genetic studies suggest those folks with a better sense of humor have a shorter allele of gene 5-HTTLPR. In addition, we know there are many physiological benefits to laughter. Oxygenation is increased, cardiac function is improved, stress hormones, such as cortisol and adrenaline, are reduced, the immune system is charged up, and the dopaminergic system, which fights depression, is strengthened.

Norman Cousins, a past Adjunct Professor at UCLA, in his book Anatomy of an Illness as Perceived by the Patient, and in an article in The New England Journal of Medicine, wrote about how he lowered his pain levels from ankylosing spondylitis, from a 10 to a 2. Ten minutes of laughter gave him two hours of pain-free sleep. Much of this laughter came from watching TV. Nowadays, if one is over 13 years old, one might need to find a different medium.

We’re told that laughing 100 times is equal to 10 minutes on a rowing machine or 15 minutes on an exercise bike. Perhaps one could frequent a comedy club nightly and skip those painful, daily exercises. Humor helps us when times are stressful, when we’re courting, and when we’re depressed. Students enjoy their teachers, pay more attention, and remember more information when humor is added to classroom instruction. Humor promotes better bonding between student and teacher, and between most couples. It also helps with hostage negotiations.

A Darwinian Scenario

If our sense of humor came about by tiny steps, like other functions, as proposed by Charles Darwin, scientists have yet to find proof of it. Think of it: can hearing the beginning words of a joke even be funny? Is there any benefit to survival with one-word jokes that eventually become two- and three-word jokes? I, doubt it, but that’s just my personal opinion. 

Fish talk by means of gestures, electrical impulses, bioluminescence, and sounds like hard-to-hear purrs, croaks, and pops. But, did they (or could they) bring their jokes ashore millions of years ago? Of course, there’s no evidence of that. Yet? Just maybe one might envision the fish remaining in the water teasing the more adventuresome fish about their ooohs and aahs, issued while walking across burning-hot sands. 

Tickling a Rat

Laughing while being tickled is not the same as having a sense of humor. The response to someone reaching into one’s armpit is a neurological and physiological reaction to being touched. For some, tickling is torture. I had one rather serious female patient, who, when undressed and covered with a sheet, was ticklish from her neck to her toes. She was nearly impossible to examine. Sometimes she would start laughing as I approached her.

One can tickle a rat, and given the right equipment, record odd utterances that might be laughter. But it might easily be profanity. Some say one can tickle a sting ray, but others say the animal is suffocating. Attempts to tickle a crocodile and other wild animals have not been conducted, as far as I’m aware, in any depth. Also, such attempts are not recommended.

Laughing is clearly part of the human package, part of our design. As I see it, there can only be two possible origins. Humor evolved very, very slowly, or it came about more quickly by intelligent design. Negative feedback loops might argue against the slow development. Some fringe thinkers might speculate that extraterrestrials passed on their sense of humor to us, millions of years ago, but, if so, jokes about the folks in the Andromeda galaxy are on a different wavelength. Jokes about Uranus, of course, are local.

Sorry About that Last One, Folks

A sense of humor varies from person to person, much like height, weight, and abdominal girth. Plus, there are gender differences. Women like men who make them laugh; men like women who laugh at their jokes. Comedians say a sense of humor is a mating signal indicating high intelligence. People on Internet dating sites often ask each other about their sense of humor. Of course, we all have great senses of humor. Just ask anyone.

A sense of humor is often highly valued. Couples get along better when they have similar senses of humor. Mutation is more likely to ruin a good joke than help it. A serious mutation might take out the entire punchline. Jokes about a partner’s looks or clothes are to be avoided. They might lead to domestic abuse. Happy tears are chemically different from sad tears. Both are different from the tears that cleanse the eye with each blink or react to infections. Can anyone explain that? Could specific tears have come about by accident?

We know laughing is a normal human activity. Some days are better than others. Human babies often smile and giggle before they are two months old, years before they will understand a good riddle. Deaf and blind babies smile and giggle at virtually that same age. Is that present to make them more lovable? Children laugh up to 400 times a day, adults only 15 times per day. This could mean we need to hear many more jokes on a daily basis.

What Humor Means

 We all think we know what humor means, but because it can vary among people, we really don’t. An amusing joke told man-to-man might be a nasty joke if told man-to-woman. Or, the other way around. Humor tends to be intangible. It’s somewhat like certain foods tasting good to you, but maybe not to me. Too salty versus needs more salt? Or sweetener? I once told my medical partner that my wife and I had just seen the funniest movie we had ever seen. He and his wife went out that very night to see it and didn’t find anything in it funny. Nothing at all! Not even the funniest scene I have ever seen in a movie. Go figure. 

What does having a good sense of humor mean? Might it be reciting a lot of relevant jokes from a repository, making up funny quips during conversations, or laughing a lot at most anything except someone else’s pain? Or a mix?

There’s a laughter-like sound that is made by chimps, bonobos, and gorillas while playing. But does it mean there’s a sense of humor at work, or monkey profanity? They might be calling each other bad names. Octopuses play but don’t smile orlaugh, we think. Dolphins “giggle” using different combinations of whistles and clicks. It does seem like they are laughing at times, but nobody knows for sure. Maybe it’s just a case of anthropomorphizing. The dolphin family has been around approximately 11 million years and the area of their brain that processes language is much larger than ours. They’ve had plenty of time to come up with several good ones.

Koko the Humorous Gorilla

Perhaps, the most interesting case was Koko the gorilla who was taught to sign. She recently died after 46 years. Her vocabulary was at least 1,000 words by signing and another 2,000 words by hearing. Some say she was a jokester. She loved Robin Williams. Maybe adored him. The two would play together for hours. Koko seemed to make up jokes. She once tore the sink out of the wall in her cage; when asked about it, she signed that her pet cat did it. However, the cat wasn’t tall enough.

 So I ask again, could a sense of humor have come about by numerous, successive, slight modifications, a Darwinian requirement? If humor fails that test, might humor be the elusive coup de grace for naturalism? Since irreducible complexity, specified complexity, and topoisomerases haven’t landed the KO to Darwin’s weakening theories, might the answer just be as simple as laughing at them?

If a sense of humor were just a variation on tickling, my guess is that comedians would come off the stage or hire teenagers to walk among their audiences to tickle everyone. Imagine being dressed up for the night, maybe eating a fancy meal or drinking expensive champagne, and some grubby kid, who’s paid minimum wage, is reaching into your armpits.

Why Laugh at All? 

Is a sense of humor a byproduct, an accident, or was it installed on purpose? For better health? There definitely seems to be a purpose. Could it be a coping mechanism? Is it the way to meet the right mate? Surely, that must be part of it.

The only evolution-related quip I could think of sums up this discussion rather well:

A little girl asked her mother, “How did the human race come about?”

The mother answered, “God made Adam and Eve. They had children, and so all mankind was made.”

A few days later, the little girl asked her father the same question. The father answered, “Many years ago there were apelike creatures, and we developed from them.”

The confused girl returned to her mother and said, “Mom, how is it possible that you told me that the human race was created by God , and Papa says we developed from ‘apelike creatures’?”

The mother answered, “Well, dear, it is very simple. I told you about the origin of my side of the family, and your father told you about his.”