is the birthday of Sir Vincent Wigglesworth, an English entomologist born in 1899 who elucidated the physiology of insect metamorphosis. Wigglesworth discovered a number of important insect hormones, including a crucial growth hormone made in the brain and a hormone that prevents juvenile insects from developing adult characteristics until they reach the right larval stage.
Wigglesworth learned how to manipulate levels of several hormones to radically alter the development of his insect subjects. Based on this work he formulated a coherent theory of insect metamorphosis, maintaining that hormones selectively activate particular genetic components, which in turn shape the insect's morphology and development. His 1934 textbook, Insect Physiology, is considered by many to be the foundation for this field.
Wigglesworth was knighted in 1964. He died in 1994.
[Source: Britannica Online]