[SunkenCiv]

It remains a mystery why they left [University of Leeds]

[scottinoc]

Pangaea sucked. I don’t blame the dinosaurs. They got away from the one-world globalist crap that was going on even then. Thank you, tectonics!

[null and void]

Bloody Vikings!

[Ancesthntr]

There’s no mystery why they left - the placed just sucked, what with the kings and landed aristocracy preventing upward social mobility on the one hand, and the Socialist/Communist oppression and forced poverty on the other, who would WANT to live in that suckass continent? Geez, even the pea-brains figured that one out.

[Buckeye McFrog]

Like anyone else they came to America
seeking a better life.

[BipolarBob]

Build the Wall!! Keep out T-Rex! Do it for the chillun.

[sauropod]

Read

[reed13k]

Makes perfect sense if as a result of one of the asteroid hits the temperatures plummeted and they were seeking warmer climates as a result.

Assume that asteroid was in the Gulf of Mexico as shown on your map. The ash moves East/NE right over what is labeled Europe. Even the westward movement to NA makes sense to get out of the ash pathway.