Foramen magnum
Homology weekly: Prognathy
I am going to take advantage of figures I prepared for a talk I gave recently, where I had to explain a diagnostic characteristic of ants during the introduction. As I have mentioned before, ants are peculiar among wasps and bees in that their mouthparts are directed forward, rather than downward, in a condition known as prognathy (pro-, anterior, projecting; –gnathus, jaw).

Hypognathus condition in insects (left image from Wikimedia commons; right drawing modified after Snodgrass 1935)