They were intrusive.

They had been driven in.

The question of whether they came from the same mastodon or from a different mastodon was resolved through the 3D reconstruction work that came later, in 2023.

But even in 2011, the protein analysis established something that was already significant: the embedded material was mastodon bone that had been driven into another mastodon’s rib from outside, through a channel that the CT images showed was consistent with an impact from a pointed object.

The Waters team published these findings in the 2011 Science paper.