In 2005 Üner Tan , an evolutionary biologist, discovered a family of 19 siblings, five of whom had impaired cognitive abilities, cerebellar hypoplasia, dysarthric speech and habitual quadruped gait in the hands and feet. He interpreted these symptoms as examples of human devotion , indicating how “they can provide us with some important clues about the transition from quadruped to standing.”
Baptized with the name of Üner Tan syndrome, or simply as UTS , the biologist indicated that the presence of a mutation in a receptor gene would be the cause of some of these symptoms, although it is true that these genetic associations seem to explain only a part of this syndrome.
To back up their claim, Tan and his fellow researchers argued that people with this syndrome use “primate-like” diagonal sequence quadrupedalism, a type of gait that distinguishes primates from most other mammals.
And we can do a simple and simple test at home: once you finish reading our article and get up from the chair, when walking, observe how your right arm swings forward when you take a step with your left foot. And then look at your cat or dog: their right forelimb and leg move forward together, a step known as a lateral sequence .
However, recent research has shown how people with Üner Tan syndrome walk differently than non-human primates – they put their weight on their wrists, not their knuckles.
A few years later, in 2014, researchers at the University of Texas at Austin (United States) analyzed 518 quadruped steps of images of members of the Turkish family with this syndrome, in addition to video sequences of other families. And the results of the analysis were published in PLoS One .
They found that individuals with Üner Tan syndrome used almost exclusively the lateral sequence , not the diagonal sequence (quadruped steps). In fact, the diagonal sequence was only used very occasionally and was not the preferred gait.
The team of researchers also found that the quadrupedalism exhibited by people with this syndrome resembles that of other adults who are asked to walk quadruped in an experimental setting. However, unlike the volunteers who have participated in these experiments, those who do have UTS can move quite effectively on all fours.
In other words, the researchers found that quadrupedalism in physically disabled or healthy adults could be explained using biomechanical principles rather than merely evolutionary assumptions.
In other words, her walking would be more of a by-product of a neurological and hereditary condition, which complicates her sense of balance. And, to adapt, they have developed quadruped .





