It is an excellent way to soother the tension that accompanies an encounter. In our own society, polite conversation has replaced physical grooming, but other may serve similar functions. Females groom mainly with their immediate family, and with certain males. Males whose relationship is tense may spend long sessions grooming, but those whose relationship is hostile or unresolved do not groom together. In relaxed situations, young chimps spend much time playing.
Juveniles play more vigorously with wrestling and chasing.
When playing, chimps show a play face, with the lower teeth bared, and they give hoarse panting laughter. Even adult chimps play together on rare occasions. Mating An oestrous female often attracts a group of males. She may mate with any of them, even infants and juveniles, or a high-ranking make may munopolize her. A male initiates mating by showing unmistakable signs of his readiness, and beckoning to the female or shaking branch.