Julian Huxley (1887-1975) is remembered as one of the most eminent biologists and science writers of the 20th century. He's less well known for what he considered to be his true life's work: the establishment of a new religion he called "evolutionary humanism."
Huxley was the grandson of Charles Darwin's friend and "bulldog," Thomas Henry Huxley, and the brother of novelist Aldous Huxley, who wrote Brave New World. He was also one of the architects of the "Modern Synthesis" that ultimately united Darwinian evolution and Mendelian genetics.
Huxley abandoned his traditional academic career in the early 1930s to write for popular audiences and by the 1950s, he was arguably the world's most prominent and authoritative voice on scientific matters. Huxley was a sort of early twentieth century version of Neil DeGrasse Tyson, and historians have come to refer to him as the "statesman of science." A committed leftist, he argued fiercely argued that science had failed to prove any innate racial differences (although he personally suspected such differences existed). He was also an ardent and unrepentant eugenicist.