Final answer:
Non-human primates communicate non-verbally through visual cues like facial expressions and body postures, gestural communications such as hand signs which can evolve into protolanguage, and tactile interactions exemplified by grooming and embracing, which aid in social bonding.
Step-by-step explanation:
Non-human primates use a variety of non-verbal communication methods such as visual cues, gestural communications, and tactile interactions.
For instance, primates utilize visual communication through facial expressions and body movements. A male chimpanzee may display dominance or warn others by raising his arms or staring, while a fearful grin might indicate submission or non-confrontation.
Gestures are also a significant part of primate communication. This includes hand signs, leading to protolanguage in apes when trained by humans. Along with this, primates communicate through touch, seen in grooming practices, embracing, or lip contact, which helps in maintaining social bonds.
Overall, these non-verbal forms of communication are not just limited to primates but are prevalent in the animal kingdom. They serve critical functions in conveying messages related to territory, food, predators, and mating signals.