He graduated from La Jolla High School in 1944, and studied math and science at Occidental College in Los Angeles, completing a double major in pre-med and psychology.
Following the route of the Portolá expedition of 1769 to make photos to illustrate a text derived from diaries of the trekkers, Crosby rode 600 miles on muleback on remote trails.
[2] Crosby's field research, writing, photography, and advocacy of the Great Mural cave paintings of Baja helped the region to be named a UNESCO World Heritage Site in 1993.
His views were vindicated in 2022 with the publication of a scientific paper detailing the results of an extensive carbon-dating study conducted by a team of geoscientists and archeologists from Australia, Mexico, and Argentina.
[10] Some of Crosby's early photography is collected in the book Tijuana 1964: A Photographic and Historic View (SDSU Press, 2000); and his only novel is Portrait of Paloma (Sunbelt, 2001).