Complex sentence: Also, the historical Verne would have been in his mid-thirties at the time of that conflict, whereas Chris Demetral, the actor who portrayed him on television, was in his mid-twenties.
Split into simpler sentences: Also, the historical Verne would have been in his mid-thirties at the time of that conflict. Whereas Chris Demetral, the actor who portrayed him on television, was in his mid-twenties.