We often take yawning as a sign of boredom or a short attention span, but a new study suggests that yawns may be indicative of something more positive: high intelligence. According to the research conducted by a team the State University of New York at Oneonta, yawn length is correlated with brain size, and the longer the yawn, the more intelligent the species.

Yawning increases the blood flow to the brain by allowing us to have a deeper inhalation of air, replacing warmed blood in the brain with cooler blood from the heart, Stat News reported. However, according to the recent study, the longer and more powerful the yawn, the greater its results. This is why it is usually the most advanced and intelligent species that yawn the longest. According to lead study author, Dr. Andrew C Gallup, in an email to Medical Daily, this may be because "animals with more neuron-rich brains would need to yawn longer."

As for intelligence differences in a single species, Gallup told Medical Daily that he would hypothesize: "based on our between-species analysis, it might be expected that the same findings would hold true within a species," though he didn't have the data to make definite conclusions.

For the study, a team of researchers led by Gallup measured the average yawn length of 109 individuals from 19 species, including rabbits, elephants, cats, dogs, and, of course, humans. While one might expect to see a connection between yawn length and jaw size, instead the team noted that yawns seemed to be more closely related to the species' overall brain size. For example, Stat News reported that gorillas, camels, horses, lions, walruses, and elephants all had longer yawn durations than humans despite having far bigger jaws.

Just like yawning, lazy behavior may also be getting a bad reputation. Laziness is frowned upon in cultures throughout the world, but a 2016 study suggests that it's the purposeful deviation from what is expected that makes lazy people so smart. According to the research, lazy people are actually more thoughtful than active individuals, and while active individuals grow bored when they have nothing to do, lazy individuals are more likely to have deep insightful thoughts during moments of down-time.

Yawn length is not the only strange indication of intelligence. According to a 2015 study, although sarcasm may not be the number one trait you look for in a potential partner, it could be a sign of high intelligence. In an experiment, the researchers from Harvard University noted that volunteers who made sarcastic comments were often better able to find creative solutions to a cognitive task, and completed the task far more often than less-sarcastic volunteers.

Along the same lines, using foul language is another trait often frowned upon, but once again science has suggested that intelligent individuals may be inclined to swear more than their less-gifted counterparts. A 2016 study linked swearing to verbal fluency, and suggested that the ability to use more curse words was a sign of a large and complex vocabulary.

Source: Gallup AC, Church AM, Pelegrino AJ. Yawn duration predicts brain weight and cortical neuron number in mammals. Biology Letters . 2016

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