Look at a primate or a Neanderthal skull and compare it with a modern human's. Notice anything missing? We have one feature that primates, Neanderthals, archaic humans--any species, for that matter--don't possess: a chin.
Aquarius was pasted down from Lucy's mom. Possibly when Lucy was younger she would play with her moms celestial spirits.This is the saddest and sweetest, cause anyone who watched fairy tail would know how deeply Aquarius cared for Lucy