1) JBS haldane 2) English biologist and author 3) English boy name 4) Geneticist 5) He had a handle on biology 6) John burdon sanderson haldane Found on https://www.crosswordclues.com/clue/haldane
[n] - Scottish geneticist (son of John Haldane) who contributed to the development of population genetics 2. [n] - Scottish physiologist and brother of Richard Haldane and Elizabeth Haldane 3. [n] - Scottish writer and sister of Richard Haldane and John Haldane (1862-1937) 4. [n] - Scottish statesman and brother of Elizabeth and ... Found on http://www.webdictionary.co.uk/definition.php?query=Haldane