Why Are Humans Ticklish?

iStock/andresr
iStock/andresr

Fabian van den Berg:

There are a few ideas about why humans experience ticklishness and there are also two kinds of tickling. One of them is a defense mechanism or warning sign that something moving is on you. Think parasites on your skin or ... no, don’t think about that. The fancy name for that is knismesis. This is the kind of tickling you feel when something soft brushes up against you. Usually, this type of tickling doesn’t make you laugh; It tends to give you goosebumps, and feel a bit uncomfortable.

Another aspect of tickling has to do with the specific spots that are ticklish. The fancy name for this one is gargalesis. This kind of tickling is more intense and leads to uncontrolled laughter. Gargalesis isn’t as straightforward as knismesis, and most likely serves some kind of social aspect and helps us bond.


Quora

There are specific spots that are ticklish in this latter way, and those are important for parents and children to form bonds. When we grow up those same spots are also erogenous zones, which help with mating, another social activity we engage in.

That these spots are also vulnerable areas on our bodies is probably no coincidence. Some experts think there is an aspect of tickling behavior meant to teach youngsters to protect their most vulnerable areas.

But other animals tickle, too. Our close cousin the chimpanzee tickles during play, though they make more of a panting, out-of-breath sound when they are laughing. They enjoy it, which they show by not leaving you alone afterward because they want you to keep going.

Elephants can be tickled as well, but my favorite is the rat.

A woman plays with her pet rat
iStock/Imagesbybarbara

There was a study where it was someone’s job to tickle rats (that must look amazing on your resume). The researchers in question were like, "Come tickle rats with me." Fun aside, this was serious research. It was known that rats make specific high-frequency noises when they play or have sex, noises of enjoyment (kind of like laughing). When they tickled the rats they made the same noises, indicating that the rats were enjoying being tickled, similar to the way humans do. It activates brain areas and pathways that also light up when humans experience joy (at least, the areas analogous to ours).

But a note must be made here: We are often quick to ascribe human emotions to animals, which can be dangerous. Animals like chimps and rats seem to enjoy tickling, so there’s reason to think they experience it in a positive way. But not all animals are like that—so experts aren't 100 percent sure they really like being tickled all that much. (Unfortunately, we can’t ask them.)

A tragic example of misinterpretation is the slow loris. These critters can be tickled, but they don’t like it. What humans interpret as enjoyment is actually fear, making the playful behavior in humans or primates literal torture for this cute-looking animal.

Tickling likely serves as a warning signal and training to protect ourselves. It has a secondary feature in humans, other primates, and rats it seems: to facilitate social bonding. But be careful who you tickle—not all animals experience the same enjoyment (some humans don’t like it either).

This post originally appeared on Quora. Click here to view.

What Happened to the Physical Copy of Martin Luther King's 'I Have a Dream' Speech?

AFP, Getty Images
AFP, Getty Images

On August 28, 1963, Martin Luther King Jr. stood on the steps of the Lincoln Memorial and gave a speech for the ages, delivering the oratorical masterpiece "I Have a Dream" to nearly 250,000 people.

When he was done, King stepped away from the podium, folded his speech, and found himself standing in front of George Raveling, a former Villanova basketball player who, along with his friend Warren Wilson, had been asked to provide extra security around Dr. King while he was speaking. "We were both tall, gangly guys," Raveling told TIME in 2003. "We didn't know what we were doing but we certainly made for a good appearance."

Moved by the speech, Raveling saw the folded papers in King’s hands and asked if he could have them. King gave the young volunteer the speech without hesitation, and that was that.

“At no time do I remember thinking, ‘Wow, we got this historic document,’” Raveling told Sports Illustrated in 2015. Not realizing he was holding what would become an important piece of history in his hands, Raveling went home and stuck the three sheets of paper into a Harry Truman biography for safekeeping. They sat there for nearly two decades while Raveling developed an impressive career coaching NCAA men’s basketball.

In 1984, he had recently taken over as the head coach at the University of Iowa and was chatting with Bob Denney of the Cedar Rapids Gazette when Denney brought up the March on Washington. That's when Raveling dropped the bomb: “You know, I’ve got a copy of that speech," he said, and dug it out of the Truman book. After writing an article about Raveling's connection, the reporter had the speech professionally framed for the coach.

Though he displayed the framed speech in his house for a few years, Raveling began to realize the value of the piece and moved it to a bank vault in Los Angeles. Though he has received offers for King’s speech—one collector wanted to purchase the speech for $3 million in 2014—Raveling has turned them all down. He has been in talks with various museums and universities and hopes to put the speech on display in the future, but for now, he cherishes having it in his possession.

“That to me is something I’ll always be able to look back and say I was there,” Raveling said in the original Cedar Rapids Gazette article. “And not only out there in that arena of people, but to be within touching distance of him. That’s like when you’re 80 or 90 years old you can look back and say ‘I was in touching distance of Abraham Lincoln when he made the Gettysburg Address.’"

“I have no idea why I even asked him for the speech,” Raveling, now CEO of Coaching for Success, has said. “But I’m sure glad that I did.”

In What Field Was Dr. Martin Luther King Jr. a Doctor?

Express Newspapers/Getty Images
Express Newspapers/Getty Images

Martin Luther King Jr. earned a doctorate in systematic theology from Boston University in 1955. He’d previously earned a Bachelor of Arts from Morehouse College and a Bachelor of Divinity from Crozer Theological Seminary. His dissertation, “A Comparison of the Conception of God in the Thinking of Paul Tillich and Henry Nelson Wieman,” examined the two religious philosophers’ views of God in comparison to each other, and to King’s own concept of a "knowable and personal" God.

In 1989, some three decades after King had earned his doctorate, archivists working with The Martin Luther King Papers Project discovered that King’s dissertation suffered from what they called a “problematic use of sources.” King, they learned, had taken a large amount of material verbatim from other scholars and sources and used it in his work without full or proper attribution, and sometimes no attribution at all.

In 1991, a Boston University investigatory committee concluded that King had indeed plagiarized parts of his dissertation, but found that it was “impractical to reach, on the available evidence, any conclusions about Dr. King's reasons for failing to attribute some, but not all, of his sources.” That is, it could have been anything from malicious intent to simple forgetfulness—no one can determine for sure today. They did not recommend a posthumous revocation of his degree, but instead suggested that a letter be attached to the dissertation in the university library noting the passages lacked quotations and citations.

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