Sir Alan Sterling Parkes was an influential figure in the field of reproductive biology in the 20th century, with contributions to the field of reproductive endocrinology in Britain in the 1920s and 1930s.

Along with Christopher Parkes and Audrey Smith, Parkes worked at the National Institute for Medical Research during the 1950s where they jointly discovered the use of glycerol to protect against damage during the freezing and storage of animal sperm.

This led to a worldwide revolution in artificial insemination in cattle, and created a new branch of biological science, known as 'cyrobiology'.

He went on to study the influence of pheromones on mammalian reproduction, working with wild animals at the Nuffield Unit of Tropical Animal Ecology in Uganda.

After retirement from the academic field, he became a consultant in the conservation and captive breeding of green sea turtles in the Cayman Islands.