suck self. self-tickle 1 5 self-tickle See tickle self with object. semen Whitish rubbery liquid containing sperm ejected by penis. See ejaculate. See Fig. 33. Fig. 33 Semen: Semen drips from females bottom after copulation Semliki Study area of Pan troglodytes schweinfurthii within Toro-Semliki Wildlife Reserve, Uganda. Research organized by K. Hunt from 199 to present. senescence Symptoms of old age are presbyopia, cataract, greying hair on head, bent and balding back, worn teeth, loss of teeth, lack of estrus, slow movement, avoidance of climbing tall trees, reduced range, etc. See video. separate Party splits into two or more smaller parties or subgroups. See video. separating intervention See intervene to separate. sexual skin Anogenital region of females. See swelling of sexual skin. See Fig. 34. S 1 shake