penis with foot Rub penis up and down with own heel, toe or sole. Few juvenile, adolescent and adult males do so, without ejaculation. Cf. shake penis. See video. F funny face Adult male, Alofu, shows unusual facial expression to estrous females and adult males. Function unknown, but as he showed funny face to female unwilling to follow him despite frequent solicitation for consortship, function may be to reassure. See video. G G gallop Goodall: Fastest run of the chimps. van Hooffs Gallop. Pikas Gallop?. See video. gang attack See attack concertedly. Gashaka-Gumti Study area of Pan troglodytes vellerosus within Gashaka-Gumti National Park, Nigeria. Research organised by Sommer from 2002 to present. gaze Includes stare fixedly, peer, and watch. See video. genital inspection See inspect genitals. genito-genital contact