June 3:
(1) (1723) Italian physician and naturalist Giovanni Antonio Scopoli is born. He published many books and reports, such as De Hydroargyro Idriensi Tentamina, which was about mercury poisoning among mercury miners.
(2) (1873) German-born pharmacologist and psychobiologist Otto Loewi was born. He is credited for discovering the brain chemical acetylcholine, for which he won the 1936 Nobel Prize in Physiology or Medicine.
(3) (1879) American biologist Raymond Pearl is born. He is credited as being one of the founders of biogerontology, a sub-field of gerontology concerned with the biological aging process.