obligatory fun fact: the word ‘cretaceous’ comes from the latin word for ‘chalk’ (creta), because the big chalk deposits in western europe were made in the cretaceous period. so next time you’re falling asleep in class, just remember the writing on the blackboard you’re totally ignoring is actually made of dead algae that lived alongside t-rexes.

…that is, unless you’re teacher uses gypsum-based chalk… in which case never mind.