Clue: Game show guest detailed elephant's place in history (9)
Answer: PANELLIST
Explanation: Definition: Game show guest
An envelope ('place in') of NELLI[e] ('elephant') minus its (her) last letter ('detailed') in PAST ('history'). was a children's song of a date which fixes it in my memory. The Wikipedia link includes the snippet that the song is often used to give the right rhythm for CPR.