On the crista sagittalis externa of Pan troglodytes.
D000367:Age Factors; D000818:Animals; D008297:Male; D009777:Occipital Bone / Q000033:anatomy & histology; D002679:Pan troglodytes / Q000033:anatomy & histology*; D010294:Parietal Bone / Q000033:anatomy & histology; D012886:Skull / Q000033:anatomy & histology*