Breakfast cereal he launched the Cornflakes brand, which overnight captured a national market. Soon there were forty rival manufacturers in the Battle Creek area. His brother William K. Kellogg (1860–1951) worked for him for many years until, in 1906, he broke away, bought the rights to Cornflakes, and set up the Kellogg Toasted Corn Flake Company. William Kellogg discarded the health food concept, opting for heavy advertising and commercial taste appeal. Later, his signature on every package became the company trademark. The second major innovator in the cereal industry was Charles W. Post, a salesman who was admitted to Kellogg's sanitarium as
Winthrop Kellogg never as an animal, particularly a pet" . It would be Robert Yerkes who would help Kellogg with his plan. Kellogg received the Social Science Research Council fellowship to work at the Yale Anthropoid Station in Florida in order to prepare for the project in 1931. That summer the Kellogg family moved to Florida. To his surprise, soon after arriving Kellogg learned that another post-doctoral fellow Carlyle Jacobsen had been studying an infant ape since its birth a year prior. To Kellogg's benefit, there had been no clear attempt to "humanize the ape". Shortly after arriving, and earlier than expected,