Pete Moore, an original member of the Miracles, the hitmaking Motown group led by Smokey Robinson, and a co-writer of some of its most enduring songs, died in Las Vegas on Nov. 19, his 79th birthday.

His wife, Tina, said the cause was complications of diabetes.

Mr. Moore’s credits included three melancholy Top 20 hits that were released in 1965, during an especially dynamic period for Motown and the Miracles: “Ooo Baby Baby,” written with Mr. Robinson; “The Tracks of My Tears,” with Mr. Robinson and the guitarist Marv Tarplin; and “My Girl Has Gone,” with Mr. Robinson, Mr. Tarplin and the group’s Ronnie White.

Adam White, the author, with the former Motown Records executive Barney Ales, of “Motown: The Sound of Young America” (2016), said in an email that this trilogy of Miracles songs “defines their talent and their art better than anything else.”

He added, “A measure of Pete Moore’s importance to the Miracles lies in the personal: that he and Smokey were friends from childhood; that he was in the earliest incarnations of the group — and that he was the best man at Smokey’s wedding.”