David Felton was a writer on Beavis and Butt-head, writing various episodes and parts for the books; he also wrote Daria's first appearance, "Scientific Stuff". Trying to establish any specific credits is difficult: there's very little record of who wrote what and the ending credits are not included in the DVDs. We're only aware he wrote "Scientific Stuff" because Mike Judge credited him in the Beavis and Butt-head: The Mike Judge Collection feature "Taint of Greatness (Part 1)".
Judge says that he and Felton collaborated on the character of Daria Morgendorffer; Judge credits him for coming up with Daria's character, as well as suggesting she dress "like Lynda Barry". John Garrett Andrews, who drew the initial Daria design, has said he thinks "Morgendorffer" came from Felton's mother's maiden name.
Before writing for the show, he worked for The Los Angeles Times and won a Pulitzer for his coverage of the Watts Riots. Recent work by Felton includes the Deep Listening Institute, a non-profit foundation promoting the work of composer Pauline Oliveros.