Researchers have found that great apes twirl around on purpose to make themselves dizzy.
Academics from the University of Warwick and the University of Birmingham suggest the findings may provide evidence that people develop a desire to seek altered mental states and actively manipulate their mood and perception of reality.
The study is based on observations of online videos of great apes — gorillas, chimpanzees, bonobos and orangutans — spinning to make themselves consciously dizzy.
dr Adriano Lameira, Associate Professor of Psychology at the University of Warwick, who co-led the study, said: “Every culture has found a way of avoiding reality through dedicated and particular rituals, practices or ceremonies.
“This human trait of seeking altered states is so universal historically and culturally that it raises the intriguing possibility that this is something that may have been inherited from our evolutionary ancestors.
“If this were indeed the case, it would have tremendous implications for how we think about modern human perceptual abilities and emotional needs.”
The research team came across viral video of a male gorilla spinning in a pool and continued the research on YouTube.
They found more videos of spinning gorillas, chimpanzees, bonobos, and orangutans.
Forty online videos were analyzed, and the researchers found that the primates rotated an average of 5.5 times per spinning episode, at an average speed of 1.5 rotations per second.
The animals did this three times on average, the scientists found.
Spinning speeds were compared and the study found that the animals can spin on a rope as fast as professional human dancers and circus performers, as well as dervish Muslims who participate in twirling ceremonies to achieve spiritual trance.
dr Lameira added: “Spinning alters our state of consciousness, it throws off our mind-body responsiveness and coordination, causing us to feel sick, light-headed and even elated, as in the case of children playing in merry-go-rounds, spinners -Wheels and carousels.”
He continued, “If all great apes seek dizziness, then most likely our ancestors did, too.
“We asked ourselves what role these behaviors play in the formation of the human mind.
“The monkeys did this purposefully, almost as if they were dancing – a mechanism known in humans that generally facilitates mood regulation, social bonding and heightens the senses and is based on rotational movements.
“The parallel between what the apes did and what humans did was more than coincidental.”
In the videos in which the animals used rope or vines to spin, they spun the fastest and the longest, the study found.
Some clips were compared to videos of purposeful human pirouettes, such as ballet dancing, traditional hopak dancing, dervish whirl, and aerial silk performances.
The researchers also tried spinning at these speeds and times themselves, and found it difficult to achieve the third spin at these speeds, as great apes did.
According to the study, monkeys were noticeably dizzy at this point in the videos, and they were likely to lose their balance and fall.
dr Marcus Perlman, a senior lecturer in the University of Birmingham’s Department of English Language and Linguistics, who co-led the research, explained: “This would suggest that the primates continued to turn on purpose, although they begin to feel the effects of vertigo until they they are no longer able to keep their balance.”
While previous studies attempting to understand human motivation for self-induced vertigo have focused on the use of substances such as alcohol or drugs, it is uncertain whether these or other substances would have been accessible to human ancestors.
Scientists say this new study may be more relevant in explaining the role of altered states in the evolution of the human mind.
dr Lameira said: “The further back in human history you go, the less certain we can be about the role that substance-induced experiences have played in our evolution.
“It’s not clear if our ancestors had access to mind-altering substances, or if they had the tools and knowledge to make the substance.
“For example, humans may have had access to grapes, but cannot be assumed to have the tools or knowledge to make wine.”
The researchers say more research is needed to understand the animals’ motivation for these behaviors.
The study is published in the Primates Journal.