ancillary data are often very diverse, may include maps, vegetation phenologies, and many kinds of information about human activities in the general area. human experts bring all these element s, plus their acquired skills and knowledge of related disciplines ...
Fritz Pollard and Bobby Marshall were the first black players in what is now the NFL in 1920. Pollard became the first (and until 1989, only) black coach in 1921; during the early-to-mid-1920s, the league used player-coaches and did not have separate coaching staffs.
In 1920, the inaugural season of the National Football League (NFL), 11 veterans of Major League Baseball (MLB) (including George Halas and Jim Thorpe) became the first athletes to accomplish the feat. Since 1970, only seven athletes have done so, including Bo Jackson and Deion Sanders.