Here they're talking about how hard dinosaur heads are, and telling kids not to smash heads with them, or something to that effect. I dunno, it inspired me to write this poem:
Dinosaurs are very big
And their heads are really strong
If you ever think of headbutting one
You'd be terribly, terribly wrong
Dinosaurs aren't around no more
Not even in the zoos
But if they were and you smacked into one
Your skull would split in two
Many dinosaurs are strong, stronger than they seem
Jen Connoly went ass to ass, in Requiem for a Dream