"We all share this basic machinery in cells, and it's not related to whether you're photosynthetic or whether you're phagocytes or whether you are a fungus or whether you're an animal cell. We all share the same machinery. Why? The possibility is that it's not about adaptation to the external world, it's about adaptation to these s. These pesky bacteria that went on to become a mitochondria. Maybe this conflict of interest... [that] had to be resolved somehow was what was driving a lot the elaboration of cellular machinery. It's a kind of local... intimate conflict."