Tonian Period

The Tonian Period was the earliest geological period in the Neoproterozoic Era, stretching from 1000 to 720 million years ago. During the Tonian, the supercontinent Rodinia (surrounded by the Mirovian ocena) which had formed in the Stenian, broke up.

During the Tonian, there was a large radiation in acritarchs. Animals also first appeared in the Tonian, with one example being the early sponge Otavia antiqua.

Adjacent Periods
The Tonian Period was preceded by the Stenian Period, of the Mesoproterozoic Era, and succeeded by the Cryogenian Period.