Complex sentence: The proximal radioulnar joint is similarly derived in higher primates in the location and shape of the radial notch on the ulna; the primitive form being represented by New World monkeys, such as the howler monkey, and by fossil catarrhines, such as "Aegyptopithecus".
Split into simpler sentences: The proximal radioulnar joint is similarly derived in higher primates in the location of the radial notch. The primitive form is represented by New World monkeys, such as the howler monkey, and by fossil catarrhines, such as "Aegyptopithecus".