According to his AP obituary (linked above), Mr. Takamoto had graduated high school in Los Angeles when World War II began. He and his family were sent to an internment camp, where fellow internees taught him how to illustrate. He had no other formal training, but still got a job at the Walt Disney Studios, where he worked as an assistant animator on its feature films from 1947 to 1960.
Mr. Takamoto (IMDb listing) is probably known best for his work at Hanna-Barbera, where he started in 1961. While there, he worked in various capacities on many familiar H-B series, including “The Flintstones,” “Jonny Quest,” and “Super Friends.” He designed countless characters, including Scooby-Doo, and directed the 1973 animated adaptation of “Charlotte’s Web.”
Iwao Takamoto received a 2005 Golden Award from the Animation Guild, in honor of his fifty-plus years working in animation. His name is no doubt familiar to anyone who spent Saturday mornings in the 1960s, 1970s, or 1980s propped in front of a TV, waiting through the credits for the next cartoon to begin.
[EDIT: ToonZone obituary]