Roddy McDowall was 43 in Battle for the Planet of the Apes when he played the character 'Caesar'.
That was over 51 years ago in 1973.
In 1998 he died aged 70, starring in 166 films in his career, 98 of those after Battle for the Planet of the Apes was first released. If he were alive today he would be 95.
In Battle for the Planet of the Apes, I think Roddy McDowall looks: