Doctor Sid is voiced by Donald Sutherland, a Canadian actor with a film career spanning over 50 years, whose first great successes came with three war films: The Dirty Dozen in 1967 with Lee Marvin and Charles Bronson; in 1970, as the lead Benjamin Franklin "Hawkeye" Pierce in Robert Altman's M*A*S*H (film); and as tank commander Sgt. Oddball in Kelly's Heroes, with Clint Eastwood and Telly Savalas. His voice is quite distinct, as is his son's, Kiefer Sutherland, best-known for his role as Jack Bauer on the TV action/thriller series 24.
Dr Sid is from the United States Military Force Science Division
His little book, much like Dr Henry Jones' Grail diary. There is a leaf to remind him of Gaia's plight.