what type of head anatomy would simians evolve

The end goal is to have human like beings with vestigial horns or antlers, but I am unsure of what types of horns they should be. Apparently there are three type of horn:

1. living horn-bony outgrowths covered in keratin(sheep/cow/goat)
2. antlers- which grow, die and fall of annually in adults (deer/elk/moose)
3. keratin horns- made of keratin, the stuff of hair, nail and hoof(rhino)

which of these would most feasibly develop in the common ancestor of old and new world monkeys? for example, whichever of the these three types is the lightest would be better for arboreal simians

posted over 7 years ago

Eloc‭

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