Mark Volman, a founding member of the 1960s pop-rock group The Turtles, died Sept. 5 in Nashville, Tenn., following a “brief, unexpected illness,” his representative said in a statement to People. He was 78.

Volman helped form the band with schoolmate Howard Kaylan; the group, initially known as the Crossfires, broke through in 1965 with a Top 10 rendition of Bob Dylan’s “It Ain’t Me Babe.” The Turtles went on to score wider fame with the 1967 hit “Happy Together,” which became one of the era’s best-known pop singles and helped cement the band’s place on television variety stages of the period, including a performance on The Ed Sullivan Show.

Over the course of his career, Volman performed with numerous lineups of The Turtles and remained active in live shows into the 21st century. Photographs from recent years show Volman performing on the Happy Together Tour in 2023; the veteran act continued to draw audiences with nostalgia-driven bills that paired 1960s hits with contemporary concert production.

Mark Volman performs Happy Together Tour 2023

The Turtles’ original 1960s lineup included Al Nichol, Chuck Portz, Jim Tucker and Don Murray alongside Volman and Kaylan. The band’s success in the mid-1960s grew from folk-rock and pop influences into radio staples and touring opportunities, producing a string of records that sustained its commercial profile through the decade.

Volman and Kaylan’s partnership became a lasting element of their careers; beyond The Turtles, the duo pursued other projects and collaborations over the years while continuing to be associated with the group’s catalog. Public statements about Volman’s death noted the suddenness of the illness; his representative was not immediately available for further comment.

Mark Volman and Howard Kaylan, 1970

Volman’s passing comes at a moment of renewed interest in 1960s pop and rock catalogs, as anniversaries and legacy tours have kept the era’s music in public circulation. The Turtles’ recordings, particularly “Happy Together,” continue to receive radio play and licensing placements that introduce the songs to new listeners.

Representatives of surviving band members had not released immediate statements, and details about memorial arrangements were not available. Media reports on Sept. 5 cited the statement to People announcing Volman’s death and the cause as a brief, unexpected illness.

Mark Volman’s contributions to the sound and image of 1960s American pop-rock, both as part of The Turtles and in subsequent musical endeavors, left a mark on a generation of listeners and performers. Coverage from the band’s archives and contemporaneous press documents his role in a period of rapid change in popular music, when television exposure and chart success helped define careers and legacies that endure in the decades that followed.