D. Bernard Amos (1923-2003) - a pioneer in several fields of biology. His work improved our understanding of the genetics of individuality and how this could be exploited for medical benefit. In particular, his research helped to make organ transplantations possible.
William Bateson (1861-1926) - was the famous scientist who coined the term 'genetics.' He popularised Mendelian genetics and co-discovered genetic linkage.
John Gurdon (1933- ) - British developmental biologist whose work on cloned frogs laid the foundations for somatic cell nuclear transfer, the application of which led to Dolly the sheep and other cloned animals.

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Linus Pauling (1901-1994) - Brilliant scientist who worked out the structure of proteins. He was involved in the race to discover the structure of DNA, but failed to spot it. A fact that has surprised many people who have studied his work.
Hans Spemann (1869-1941) - widely recognised as the 'father of cloning' - this German embryologist conducted groundbreaking work on embryonic induction that directs the development of cells into tissues and organs. He also theorized that cloning would be possible with differentiated cells.