PBS Eons on YT does a good job of diving into the many and extreme phases that Earth has seen. Check it out! https://www.youtube.com/watch?v=_1LdMWlNYS4&list=PLi6K9w_Ubf...

Also, Darwin wrote a lot about the extreme variations that we see in the 'balanced' ecosystem. He tallied up the birds near him and found that ~4/5ths of all the birds would die every winter. He remarked that a 10% death rate illness in humans would be considered a huge event, but that every year, nearly all the birds near him just up and die. This was in a passage on how the 'balance' that we see is really just a lot of species furiously competing with each other and trying to eek out minuscule improvements in the deadly chaos.