Starling enjoyed collaborating with
William Bayliss (1860–1924), who was on the staff of
University College London (UCL), and together they published on the electrical activity of the heart and on
peristalsis. In 1891, when he was 25, Starling married Florence Amelia Wooldridge, the widow of Leonard Charles Wooldridge, who had been his physiology teacher at Guy's and died at the age of 32. She was a great support to Starling as a sounding board, secretary, and manager of his affairs as well as mother of their four children. In 1893 Bayliss married Gertrude, Starling's sister, so the two were brothers-in-law. When Starling was appointed professor at UCL in 1899, the scientific family was even closer. Bayliss and Starling were in the newspaper's headlines when involved in the
Brown Dog affair, a controversy relating to
vivisection. Bayliss and Starling investigated
pancreatic secretion, which at that time was believed to be entirely under nervous control. They showed that whenever food or acid was put into the
duodenum some blood-borne stimulus was released, causing the pancreas to secrete. They called this substance
secretin and Starling proposed that the body produces many secretin-like molecules, and in 1905 proposed that these substances should be called
hormones. By doing this, he began a whole new biological subject, which became known as
endocrinology. ==Medical education==