Is that really James Brolin . . .

. . . in the orange shirt dancing the watusi with the amply-endowed, yellow-frilly-dress girl in the opening scene?

Doesn't look like him at all.

I wonder if it's

(1) a professional dancer and Fox just gave Jimmy Brolin billing in it to get him a credit (he was a contract player at Fox in the 60's and they were very high on his eventual leading-man potential)

(2) just another imdb mistake