part of part of Homo sapiens occipital bone zone of bone organ superior nuchal line of squamous part of occipital bone 2026-03-19T00:00:00Z A zone of bone organ forming the upper of two curved ridges on the external surface of the squamous occipital bone, extending laterally from the external occipital protuberance. It provides attachment for the trapezius, sternocleidomastoid, and splenius capitis muscles. David Osumi-Sutherland