‘Twas the night before the Cretaceous–Paleogene extinction event
And all through the Mesozoic Era,
Not a creature was stirring,
Not even a pterosaur, plesiosaur, or ammonite.

When all of a sudden
There arose such a clatter
T-Rex reared to the sky
To see what was the matter

From up in the air
Rained comets below
spelling extinction for 75%
of Earth’s reigning fish, mammals, and sea life, you know.

from Wikipedia

The burrowing mammals all snug in their nests
Lived on to diversify
While the largest of land-dwelling organisms
Were among the first species to die

But on December 24th
Santa Bronto shall ride
Reminding us of the years
He used to preside

So this year, while you hang tinsel
On your Christmas evergreen
Remember all the Archosaurs, Crocodyliforms, and Pterosaurs
Who are no longer on the scene

You can almost hear them cry
Over your roaring Christmas fire:
“Merry Evolution to all,
And to all a good RAWR!”