section_path: Infrastructure/Science and technology
section_name: Science and technology
paragraph_text: Science and technology
  
  Several important scientific and technological developments have originated in South Africa. South Africa was ranked 59th in the Global Innovation Index in 2023, up from 63rd in 2019. The first human-to-human heart transplant was performed by cardiac surgeon Christiaan Barnard at Groote Schuur Hospital in December 1967; Max Theiler developed a vaccine against yellow fever, Allan MacLeod Cormack pioneered X-ray computed tomography (CT scan); and Aaron Klug developed crystallographic electron microscopy techniques. Cormack and Klug received Nobel Prizes for their work. Sydney Brenner won in 2002, for his pioneering work in molecular biology. Mark Shuttleworth founded an early Internet security company Thawte.
  
  South Africa has cultivated a burgeoning astronomy community. It hosts the Southern African Large Telescope, the largest optical telescope in the Southern Hemisphere. South Africa is currently building the Karoo Array Telescope as a pathfinder for the €1.5 billion Square Kilometre Array project.