A long time ago, wood (Lignin) wasn’t biodegradable. Trees just piled up instead of rotting. That resulted in oil deposits. These we turn into plastics. Bacter

A long time ago, wood (Lignin) wasn’t biodegradable. Trees just piled up instead of rotting. That resulted in oil deposits. These we turn into plastics. Bacteria acquiring genes to feed on plastics would lead to closing the circle again. Although supply will be cut short when humanity gives up producing plastics.