Luigi Aloisio Galvani (September 9, 1737 - December 4, 1798) was an Italian physician, physicist, and biologist, recognized as the pioneer of bioelectromagnetics. In 1780, he discovered that the muscles of dead frogs' legs twitched when struck by an electrical spark. He coined the term animal electricity to describe the force that activated the muscles of his specimens and regarded their activation as being generated by an electrical fluid that is carried to the muscles by the nerves. Volta objected to Galvani's conclusions about "animal electric fluid", but the two scientists disagreed respectfully and Volta coined the term "Galvanism" for a direct current of electricity produced by chemical action. Thus, owing to an argument between the two in regard to the source or cause of the electricity, Volta built the first battery in order to specifically disprove his associate's theory. Galvani died in 1798 at the age of 61. Today the study of galvanic effects in biology is called electrophysiology.