John Burdon Sanderson Haldane popularly known as JBS Haldane was a British-born Indian geneticist and evoluti- onary biologist. He was one of the founders of population genetics along with Ronald Fisher and Sewall Wright.

Haldane was born in Oxford to physiologist John Scott Haldane and Louisa Kathleen Haldane, and descended from an aristocratic intellectual Scottish family. His father was a scientist, a philosopher and a Liberal, and his mother was a Conservative. Haldane took interest in his father’s work very early in his childhood. Haldane was educated at Eton and New College Oxford and served in the British Army during the First World War. In 1926, Haldane married Charlotte Burghes, a young reporter of the Daily Express. Following separation in 1942, they divorced each other in 1945, and later he married Helen Spurway.

Between 1919 and 1922 he was a Fellow of New College, Oxford, then moved to Cambridge University, where he accepted a Readership in Biochemistry at Trinity College and taught there until 1932. In 1923, in a talk given in Cambridge, Haldane, foreseeing the exhaustion of coal for power generation in Britain, proposed a network of hydrogen-generating windmills. This is the first proposal of the hydrogen-based renewable energy economy. During his nine years at Cambridge, Haldane worked on enzymes and genetics, particularly the mathematical side of genetics. Haldane wrote many popular essays on science that were eventually collected and published in 1927 in a volume entitled ‘Possible Worlds’. After accepting a position as Professor of Genetics, Haldane moved to University College, London where he spent most of his academic career. Four years later he became the first Weldon Professor of Biometry at University College, London.

Population Genetics and the Briggs-Haldane Equation:- In 1925, G. E. Briggs and Haldane derived a new interpretation of the enzyme kinetics law.   Haldane made many contributions to human genetics and was one of the three major figures to develop the mathematical theory of population genetics. His greatest contribution was in a series of ten papers  which were the major series of papers on the mathematical theory of natural selection. It treated many major cases for the first time, showing the direction and rates of changes of gene frequencies. It also pioneered in investigating the interaction of natural selection with mutation and with migration. Haldane’s book, ‘The Causes of Evolution’ (1932), summarized these results. Haldane introduced many quantitative approaches in biology.  He was the first to calculate the mutational load caused by recurring mutations at a gene locus, and to introduce the idea of a “cost of natural selection”.

Haldane and India:- Influenced by a number of factors, Haldane came to India, initially to the Indian Statistical Institute (ISI).   His interest in India was also due to his interest in biological research, belief that the warm climate would do him good and that India offered him freedom and shared socialist dreams. At the ISI, he headed the biometry unit and spent time researching a range of topics and guiding other researchers around him. He was keenly interested in inexpensive research and brought observations on Vanellus malabaricus boasting that he made them from the comfort of his backyard. Haldane took an interest in anthropology, human genetics and botany. He advocated the use of Vigna sinensis (cowpea) as a model for studying plant genetics. He took an interest in the pollination of the common weed Lantana camara and in the study of floral symmetry. His wife, Helen Spurway, conducted studies on wild silk moths. He was also interested in Hinduism and after his arrival he became a vegetarian. 

Unable to get along with the director of ISI, Haldane resigned in February 1961 and moved to a newly established biometry unit in Orissa.

Haldane was a famous science populariser. His essays were remarkable in predicting many scientific advances.  His book shows the effect of the separation between sexual life and pregnancy as a satisfactory one on human psychology and social life. The book was regarded as shocking science fiction at the time, being the first book about ectogenesis (the development of foetuses in artificial wombs) - “test tube babies”, brought to life without sexual intercourse or pregnancy.

 For popularizing Science, Haldane in 1952,  received the Darwin Medal from the Royal Society. In 1956, he was awarded the Huxley Memorial Medal of the Royal Anthropological Institute. Among other awards, he received the Feltrinelli Prize, an Honorary Doctorate of Science, an Honorary Fellowship at New College, and the Kimber Award of the U.S. National Academy of Sciences. Haldane died on 1 December 1964.