The epochs of known time.
During the brunch of years that postdated the creation of the Squariverse (Universe), the great phase of Clown generation began.
Epoch 2 begins at the emergence of the first Clown. Prior proto-Clownids aside, the first true Clown marks the end of the age of generation.
We are currently in Epoch 2.
The next epoch shall mark the advent of Clown Death.