Long before the wheel was invented, mankind walked on all fours. Walking upright freed the hands for carrying and manipulating tools. It also allowed for traveling longer distances and eventually, endurance running. According to Chris Stringer, a leading anthropologist at the Natural History Museum in London, it may have been a key step that led our ancestors’ brains to grow. In this 21st century, where technology and medical science is at its peak, it might be hard to imagine that human beings still walk on all fours. Five members of the Ulas family from Turkey exhibit this behavior, and for years, scientists have been trying to find out exactly why this has happened.
The world first learned of the Ulas family in 2005, following the popularity of the BBC documentary, “The Family That Walks On All Fours”.
The Ulas family consists of 21 members. The parents had a total of 19 children, which was more than the local standards in the remote Kurdish village. Of the 19 children, 12 were born healthy and showed no signs of disabilities. Seven of them had health issues and only six of them survived into adulthood. Five of the surviving members of the family walked on all fours while the sixth one was able to walk normal. However, he had trouble balancing; often appearing as if he was drunk all the time.
The five siblings are four sisters, Safiye, Hacer, Senem, Emine, and a brother Hüseyin. All five of them, aged between 18 and 34, get around by ‘bear crawling’ on their feet and palms – and can only stand upright for a short time, with both knees and head flexed.
When they were first discovered in 2005, scientists rushed to learn as to why the siblings were walking on all fours. Initially, some of them thought that the Ulas family members’ quadrupedal gait was similar to the movement of primates, suggesting ‘a backwards stage in human evolution’.
Their discovery was a once in a lifetime opportunity for scientists, as well as Nicholas Humphrey, since it could provide the missing link in evolution. Nicholas Humphrey, an English neuropsychologist based in Cambridge, who is known for his work on the evolution of primate intelligence and consciousness, set out with a team of scientists to observe and study the family.
According to scientists, the siblings had rediscovered a form of locomotion which corresponds closely to the way our ancestors walked.
All six siblings live with their parents, who care and provide for them. The brother Hüseyin has been walking on all fours for more than 30 years. He can ‘bear crawl’ for miles without tiring himself. Scientists studying the family observed that the heels on Hüseyin’s hands were thickened as it was on his feet.
Turkish scientists who first discovered the family, believed that the siblings were a case of ‘backward evolution’ but professor Humphrey believed that it was more likely to be genetic. The parents are second cousins and could have easily passed a faulty gene on to some but not all of their children.
According to Prof. Humphrey, the five siblings could have inherited the same recessive genetic mutation. After spending time with the family and observing their behavior, it was becoming clear that the issue was more likely cerebellar ataxia; a disorder that occurs when the cerebellum becomes inflamed or damaged. However, all five of them showed no signs of poor hand or eye coordination and they had no trouble speaking. The sisters even loved knitting and crocheting.
When they walked, the siblings only allowed the heels of their hands to touch rough surfaces. Their fingers would only touch the surface if it was soft. Although scientists understood that there was something wrong with their brain, it still wasn’t clear why they were walking on all fours.
Walking on all fours has caused them a lifetime of misery. The villagers are hostile towards the Ulas family and children often taunt and mock Hüseyin.
The team of scientists took the siblings to a nearby hospital and performed a brain scan. The scan results showed that all five of them who walked on all fours had a shrunken cerebellum.
However, people with damaged cerebellum or no cerebellum are still capable of walking upright. German scientists collected blood samples from the family, conducted a DNA analysis and published papers suggesting that the family had genes that had been passed on for generations, which could be responsible for them walking on all fours.
This however, upset a lot of scientists since their studies showed the data to be the exact opposite. In 2014, American scientists concluded that the siblings’ walk was an adaptation to an unforeseen and rare disorder. The report was published in PLOS One and according to the study, the siblings move lateral, unlike primates who walk in a diagonal sequence. The report also suggests that the siblings’ walk is, in fact, a byproduct of a hereditary condition that causes cerebellar hypoplasia, complicating their sense of balance.
According to the parents, all five of them were born healthy and crawled like any other toddler. As time went by, the crawling slowly turned into a ‘bear crawl’, which stayed with them forever.
After various documentaries were made, the world came to know about the Ulas family. Many were saddened by the fact that the family was constantly harassed by the villagers, who also consider them to be outcasts. In order to avoid the villagers, the family was constantly moving until the parents were able to find an isolated location, far away from other homes. However, local children still find time to make their way to mock Hüseyin.
Turkish psychologist Defne Aruoba, one of the many heartfelt members of the research team, is working to setup the Ulas Foundation in hopes of rehabilitating the siblings as well as helping others with similar conditions.
Hüseyin has suffered long lasting damage, since he has been walking for more than 30 years on all fours. Apart from that, he also suffers from epilepsy, making it hard for him to recover. However, the team members are sure that the sisters have a chance at recovering, so Dr. Ali, one of the members, purchased a $30 walking frame for them. This was a turning point in their lives since the sisters were able to use the walking frame and walk normal.
Before the team left, they also erected a set of parallel bars for the siblings to hold and exercise walking upright. The scientists explain that these are only a few steps to recovery but there’s still a long way to go. Despite all this, the Ulas family remained hopeful that one day, all five of them will be able to walk upright without the help of anyone and they achieved it. Currently, all five of the siblings are able to take a few steps without any aid and are also working hard everyday to achieve their dream.
Based on their achievement to be able to walk upright, even if it is for a short period of time, most of the scientists who believe it was ‘backward evolution’, ruled out that possibility.