Uner Tan (''
Turkish'': Üner Tan) (1 May 1937 – 6 February 2022) was a Turkish
neuroscientist
A neuroscientist (or neurobiologist) is a scientist specializing in neuroscience that deals with the anatomy and function of neurons, Biological neural network, neural circuits, and glia, and their Behavior, behavioral, biological, and psycholo ...
and
evolutionary biologist
Evolutionary biology is the subfield of biology that studies the evolutionary processes such as natural selection, common descent, and speciation that produced the diversity of life on Earth. In the 1930s, the discipline of evolutionary biol ...
. He is best known for his discovery and study of the human
quadrupedal
Quadrupedalism is a form of Animal locomotion, locomotion in which animals have four legs that are used to weight-bearing, bear weight and move around. An animal or machine that usually maintains a four-legged posture and moves using all four l ...
condition he named the
Uner Tan syndrome. He taught at
Çukurova University
Çukurova University () is a public research university located in Adana, Turkey. The university features sixteen faculties, three colleges, seven vocational colleges, three institutes, and twenty-six research and application centers. Its campus i ...
until his retirement in 2004 and had previously taught at several other institutions.
Biography
Tan was born in
Ãœnye
Ünye (''Oinòe'', Οἰνόη in ancient Greek) is a municipality and district of Ordu Province, Turkey. Its area is 569 km2, and its population is 132,432 (2022). It is on the Black Sea coast, 76 km west of the city of Ordu.
Geography ...
, Turkey. He graduated from secondary school in
Çorum
Çorum () is a northern Anatolian city in Turkey. Çorum is located inland in the central Black Sea Region of Turkey and is approximately from Ankara and from Istanbul. It is the seat of Çorum Province and of Çorum District.[< ...]
and started college at
Ege University
Ege University or Aegean University () is a public research university in Bornova, Ä°zmir. It was founded in 1955 with the faculties of Medicine and Agriculture. It is the first university to start courses in Ä°zmir and the fourth oldest unive ...
, at the Faculty of Medicine, in 1956. He continued at
Göttingen University
Göttingen (, ; ; ) is a college town, university city in Lower Saxony, central Germany, the Capital (political), capital of Göttingen (district), the eponymous district. The River Leine runs through it. According to the 2022 German census, t ...
and graduated from there and the
Max-Planck Institute
The Max Planck Society for the Advancement of Science (; abbreviated MPG) is a formally independent non-governmental and non-profit association of German research institutes. Founded in 1911 as the Kaiser Wilhelm Society, it was renamed to the M ...
in 1966. He returned to Turkey at 1969 and worked at
Hacettepe University
Hacettepe University () is a public research university in Ankara, Turkey. It was established on 8 July 1967. It is ranked first among the Turkish universities by University Ranking by Academic Performance in 2021.
The university has two main c ...
in
Ankara
Ankara is the capital city of Turkey and List of national capitals by area, the largest capital by area in the world. Located in the Central Anatolia Region, central part of Anatolia, the city has a population of 5,290,822 in its urban center ( ...
, and
Atatürk University
Atatürk University () is a public land-grant research university established in 1957 in Erzurum, Turkey, in collaboration with the University of Nebraska. The university comprises 23 faculties, 18 colleges, 8 institutes, and 30 research cente ...
in
Erzurum
Erzurum (; ) is a List of cities in Turkey, city in eastern Anatolia, Turkey. It is the largest city and capital of Erzurum Province and is 1,900 meters (6,233 feet) above sea level. Erzurum had a population of 367,250 in 2010. It is the site of an ...
,
Black Sea Technical University in
Trabzon
Trabzon, historically known as Trebizond, is a city on the Black Sea coast of northeastern Turkey and the capital of Trabzon Province. The city was founded in 756 BC as "Trapezous" by colonists from Miletus. It was added into the Achaemenid E ...
and Çukurova University in
Adana
Adana is a large city in southern Turkey. The city is situated on the Seyhan River, inland from the northeastern shores of the Mediterranean Sea. It is the administrative seat of the Adana Province, Adana province, and has a population of 1 81 ...
. Tan retired in 2004, and died in February 2022, at the age of 84.
Uner Tan syndrome
According to Tan, persons affected by this syndrome walk with a
quadrupedal
Quadrupedalism is a form of Animal locomotion, locomotion in which animals have four legs that are used to weight-bearing, bear weight and move around. An animal or machine that usually maintains a four-legged posture and moves using all four l ...
locomotion and are afflicted with "
primitive" speech and severe
mental retardation
Intellectual disability (ID), also known as general learning disability (in the United Kingdom), and formerly mental retardation (in the United States), Rosa's Law, Pub. L. 111-256124 Stat. 2643(2010).Archive is a generalized neurodevelopmental ...
; he postulated that this is an example of
backward evolution
Devolution, de-evolution, or backward evolution (not to be confused with dysgenics) is the notion that species can revert to supposedly more primitive forms over time. The concept relates to the idea that evolution has a divine purpose (teleology) ...
.
He proposed the syndrome after studying the
Ulas family
The Ulas family of 19 is from rural southern Turkey. Five of the family members (except for another, who has died) walk on all fours with their feet and the palms of their hands in what is called a "bear crawl". Their quadrupedal gait had never bee ...
of rural southern Turkey, five of whom have these symptoms. The proposed syndrome was featured in the 2006
BBC2
BBC Two is a British free-to-air public broadcast television channel owned and operated by the BBC. It is the corporation's second flagship channel, and it covers a wide range of subject matter, incorporating genres such as comedy, drama and ...
documentary ''
The Family That Walks On All Fours''. After his study of the Ulas family, Tan went on to diagnose Uner Tan syndrome in several other families.
Neuroscientist
A neuroscientist (or neurobiologist) is a scientist specializing in neuroscience that deals with the anatomy and function of neurons, Biological neural network, neural circuits, and glia, and their Behavior, behavioral, biological, and psycholo ...
and
evolutionary psychologist
Evolutionary psychology is a theoretical approach in psychology that examines cognition and behavior from a modern evolutionary perspective. It seeks to identify human psychological adaptations with regard to the ancestral problems they evolved ...
Roger Keynes, psychologist
Nicholas Humphrey
Nicholas Keynes Humphrey (born 27 March 1943) is an English neuropsychologist based in Cambridge, known for his work on the evolution of primate intelligence and consciousness. He studied mountain gorillas with Dian Fossey in Rwanda; he was t ...
and medical scientist
John Skoyles have argued that the gait of these individuals is due to two rare phenomena coming together, not atavism.
First, instead of initially
crawling as
infant
In common terminology, a baby is the very young offspring of adult human beings, while infant (from the Latin word ''infans'', meaning 'baby' or 'child') is a formal or specialised synonym. The terms may also be used to refer to juveniles of ...
s on their
knee
In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the hu ...
s, they started off
learning
Learning is the process of acquiring new understanding, knowledge, behaviors, skills, value (personal and cultural), values, Attitude (psychology), attitudes, and preferences. The ability to learn is possessed by humans, non-human animals, and ...
to move around with a "bear crawl" on their feet.
[ Second, due to their ]congenital
A birth defect is an abnormal condition that is present at childbirth, birth, regardless of its cause. Birth defects may result in disability, disabilities that may be physical disability, physical, intellectual disability, intellectual, or dev ...
brain impairment, they found balancing on two leg
A leg is a weight-bearing and locomotive anatomical structure, usually having a columnar shape. During locomotion, legs function as "extensible struts". The combination of movements at all joints can be modeled as a single, linear element cap ...
s difficult.[ Because of this, their ]motor development
A motor neuron (or motoneuron), also known as efferent neuron is a neuron whose cell body is located in the motor cortex, brainstem or the spinal cord, and whose axon (fiber) projects to the spinal cord or outside of the spinal cord to directly or ...
was channeled into turning their bear crawl into a substitute for bipedalism
Bipedalism is a form of terrestrial locomotion where an animal moves by means of its two rear (or lower) Limb (anatomy), limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from ...
.[
In the BBC documentary '' The Family That Walks On All Fours'', Nicholas Humphrey refers to Uner Tan's "devolutionary" description of the Ulas family as "scientifically irresponsible."
]
See also
*'' The Family That Walks On All Fours'', documentary about the Ulas family
* VLDLR-associated cerebellar hypoplasia
References
External links
Tan autobiography
{{DEFAULTSORT:Tan, Uner
1937 births
2022 deaths
Evolutionary biologists
People from Ãœnye
Turkish scientists