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Josef Mengele (German: ['jo:zef 'meNG@l@]; 16 March 1911 - 7 February 1979) was a German Schutzstaffel (SS) officer and physician in Auschwitz concentration camp during World War II. Mengele was a member of the team of doctors responsible for the selection of victims to be killed in the gas chambers and for performing deadly human experiments on prisoners.

Mengele was born the eldest of three children on 16 March 1911 to Karl and Walburga (Hupfauer) Mengele in Gunzburg, Bavaria, Germany. His younger brothers were Karl Jr and Alois. Mengele's father was founder of the Karl Mengele & Sons company, producers of farm machinery. Mengele did well in school and developed an interest in music, art, and skiing. He completed high school in April 1930 and went on to study medicine at Goethe University Frankfurt and philosophy at the University of Munich. Munich was the headquarters of the Nazi Party. In 1931 Mengele joined the Stahlhelm, Bund der Frontsoldaten, a paramilitary organization that was absorbed into the Nazi Sturmabteilung (Storm Detachment; SA) in 1934.  In 1935, Mengele earned a PhD in anthropology from the University of Munich. In January 1937, at the Institute for Hereditary Biology and Racial Hygiene in Frankfurt, he became the assistant to Dr. Otmar Freiherr von Verschuer, a scientist conducting genetics research, with a particular interest in twins. As an assistant to von Verschuer, Mengele focused on the genetic factors resulting in a cleft lip and palate or cleft chin. His thesis on the subject earned him a cum laude doctorate in medicine in 1938. Both of his degrees were later rescinded by the issuing universities. In a letter of recommendation, von Verschuer praised Mengele's reliability and his ability to verbally present complex material in a clear manner. The American author Robert Jay Lifton notes that Mengele's published work did not deviate much from the scientific mainstream of the time, and would probably have been viewed as valid scientific efforts even outside Nazi Germany.  On 28 July 1939, Mengele married Irene Schonbein, whom he had met while working as a medical resident in Leipzig. Their only son, Rolf, was born in 1944.  The ideology of Nazism brought together elements of antisemitism, racial hygiene, and eugenics, and combined them with pan-Germanism and territorial expansionism with the goal of obtaining more Lebensraum (living space) for the Germanic people. Nazi Germany attempted to obtain this new territory by attacking Poland and the Soviet Union, intending to deport or kill the Jews and Slavs living there, who were considered inferior to the Aryan master race.  Mengele joined the Nazi Party in 1937 and the Schutzstaffel (SS; protection squadron) in 1938. He received basic training in 1938 with the Gebirgsjager (mountain infantry) and was called up for service in the Wehrmacht (German armed forces) in June 1940, some months after the outbreak of World War II. He soon volunteered for medical service in the Waffen-SS, the combat arm of the SS, where he served with the rank of SS-Untersturmfuhrer (second lieutenant) in a medical reserve battalion until November 1940. He was next assigned to the SS-Rasse- und Siedlungshauptamt (SS Race and Resettlement Main Office) in Posen, evaluating candidates for Germanisation.  In June 1941, Mengele was posted to Ukraine, where he was awarded the Iron Cross Second Class. In January 1942, he joined the 5th SS Panzer Division Wiking as a battalion medical officer. He rescued two German soldiers from a burning tank and was awarded the Iron Cross First Class, as well as the Wound Badge in Black and the Medal for the Care of the German People. He was seriously wounded in action near Rostov-on-Don in mid-1942, and was declared unfit for further active service. After recovery, he was transferred to the Race and Resettlement Office in Berlin. He also resumed his association with von Verschuer, who was at the Kaiser Wilhelm Institute of Anthropology, Human Heredity, and Eugenics. Mengele was promoted to the rank of SS-Hauptsturmfuhrer (captain) in April 1943.  In Buenos Aires, Argentina, Mengele worked as a carpenter while residing in a boarding house in the suburb of Vicente Lopez. After a few weeks he moved to the house of a Nazi sympathiser in the more affluent neighborhood of Florida, Buenos Aires. He next worked as a salesman for his family's farm equipment company, and beginning in 1951 he made frequent trips to Paraguay as sales representative for that region. An apartment in the center of Buenos Aires became his residence in 1953, the same year he used family funds to buy a part interest in a carpentry concern. In 1954 he rented a house in the suburb of Olivos. Files released by the Argentine government in 1992 indicate that Mengele may have practiced medicine without a license, including performing abortions, while living in Buenos Aires.  After obtaining a copy of his birth certificate through the West German embassy in 1956, Mengele was issued an Argentine foreign residence permit under his real name. He used this document to obtain a West German passport, also under his real name, and embarked for a visit to Europe. He met up in Switzerland for a ski holiday with his son Rolf (who was told Mengele was his "Uncle Fritz") and his widowed sister-in-law Martha, and spent a week in his home town of Gunzburg. Upon his return to Argentina in September, Mengele began living under his real name. Martha and her son Karl Heinz followed about a month later, and the three took up residence together. The couple married while on holiday in Uruguay in 1958 and bought a house in Buenos Aires. Business interests now included part ownership of Fadro Farm, a pharmaceutical company. Along with several other doctors, Mengele was questioned and released in 1958 under suspicion of practicing medicine without a license after a teenage girl died following an abortion. Worried that the publicity would lead to his Nazi background and wartime activities being discovered, he took an extended business trip to Paraguay and was granted citizenship under the name Jose Mengele in 1959. He returned to Buenos Aires several times to wrap up his business affairs and visit his family. Martha and Karl Heinz lived in a boarding house in the city until December 1960, when they returned to Germany.  Mengele's name was mentioned several times during the Nuremberg trials, but Allied forces were convinced that he was dead. Irene and the family in Gunzburg also said that he was dead. Working in West Germany, Nazi hunters Simon Wiesenthal and Hermann Langbein collected information from witnesses as to Mengele's wartime activities. In a search of the public records, Langbein found Mengele's divorce papers listing an address in Buenos Aires. He and Wiesenthal pressured West German authorities into drawing up an arrest warrant on 5 June 1959, and starting extradition proceedings. Initially Argentina turned down the request, because the fugitive was no longer living at the address given on the documents. By the time extradition was approved on 30 June 1960, Mengele had already fled to Paraguay, where he was living on a farm near the Argentine border.

Did he teach?
As an assistant to von Verschuer, Mengele focused on the genetic factors resulting in a cleft lip and palate or cleft chin. His thesis on the subject earned him a