Alister Clavering Hardy was born on 10 February 1896 in Nottingham, England. His parents were Elizabeth Clavering and architect Richard Hardy. He was educated at Oundle School, a boarding school in Peterborough. In 1914 he enrolled at Exeter College, Oxford, to study forestry.

Hardy’s education was interrupted by the First World War, during which he served in the Northern Cyclist Battalion, and later as a camouflage officer. On his return to Oxford in 1919 he opted to change his degree to zoology, reflecting his long-standing interest in naturalism. He was awarded the Christopher Welsh scholarship and graduated with distinction in 1921. He then spent some time in Naples researching marine plankton and was appointed Assistant Naturalist at the Ministry of Agriculture and Fisheries laboratory in Lowestoft.

Between 1924 and 1927, Hardy acted as chief zoologist on the Discovery expedition to the Antarctic, where he studied zooplankton and their relation to whales, as well as other marine mammals. A year after returning he took the post of Professor of Zoology at the University College of Hull. In 1942 he moved to Aberdeen to take the Regius Professorship of Natural History, and three years later he became Linacre Professor of Zoology at Oxford. After retiring in 1963, he founded what would become the Alister Hardy Research Centre, which aimed to research the phenomenon of religious experience.