Bbc Inside Science

In 2018, the International Association of Athletics Federations (IAAF) introduced new eligibility regulations for female athletes with differences in sex development (DSDs). These regulations are based on the contention that women with high levels of endogenous testosterone and androgen sensitivity have a performance advantage over their peers. South African middle distance runner, Mokgadi Caster Semenya, who won two Olympic gold medals in 2012 and 2016, and Athletics South Africa, are contesting the legality of these new regulations. The basis of their objection, at the Court of Arbitration for Sport, is that there is a lack of scientific evidence showing that endogenous testosterone concentrations substantially enhance sports performance. Caster, who is DSD herself, has lost her case and Adam turns to expert in sport, exercise and genomics at Manchester Metropolitan University, Dr. Alun Williams to explain the implications.Less than a decade ago, an entirely new branch of the ancient human tree was discover