Sir Vincent Brian Wigglesworth CBE FRS (17 April 1899 – 11 February 1994) was a British entomologist who made significant contributions to the field of insect physiology. He established the field in a textbook which was updated in a number of editions. In particular, he studied metamorphosis. His most significant contribution was the discovery that neurosecretory cells in the brain of the South American kissing bug, Rhodnius prolixus, secrete a crucial hormone that triggers the prothoracic gland to release prothoracicotropic hormone (PTTH), which regulates the process of metamorphosis. This was the first experimental confirmation of the function of neurosecretory cells. He went on to discover another hormone, called the juvenile hormone, which prevented the development of adult characteristics in R. prolixus until the insect had reached the appropriate larval stage. Wigglesworth was able to distort the developmental phases of the insect by controlling levels of this hormone. From these observations, Wigglesworth was able to develop a coherent theory of how an insect's genome can selectively activate hormones which determine its development and morphology. Source: Wikipedia (en)