thumb|Chimpanzee vocalizing
thumb|Pant-hoot made by an adult male chimpanzee, effectively demonstrating the introduction, build-up, climax and let-down phases.
The pant-hoot is a loud, structurally complex vocalization of chimpanzees. The call is generally divided into four distinct, successive phases: introduction, build-up, climax and let-down. The pant-hoot is most often produced jointly with other males, in a complementary behaviour known as chorusing, as opposed to producing the calls individually.
These loud, long-distance vocalizations are produced for numerous purposes in a variety of different circumstances and situations. Pant-hoot chorusing can be used to aid in the formation of social groups or parties amongst male chimpanzees, and used to display the dominance and strength of their party to conspecifics. Additionally, the level of pant-hooting in chimps vary based upon their individual dominance rank within a party.
Grunting is made in situations like feeding and greeting. Submissive individuals make "pant-grunts" towards their superiors.
Social bonding (affiliation)
thumb|Chimpanzee grooming, a reciprocal behaviour commonly associated with the formation of social bonds between individuals. habitat composition and genetic differentiation with respect to geographic separation and differences based upon experience and [[vocal learning.
Structure
The general structure of chimpanzee pant-hoots (introduction, build-up, climax and let-down) can be variable between populations, including instances of additions/removals of certain phrases, changes in the duration of each phrase and the rearrangement of the general sequential pattern of phrases, with these modifications being easily identified by researchers, experts and other human listeners. These structural differences may be attributed to behavioural contexts, genetic differences between members of different populations due to geographic separation, and consequently, varying habitat conditions and learning based upon experience (vocal learning).