Interestingly, our cellular mitochondria were once believed to be separate organisms.  They’re the control centers of many of our biological functions. Also, they might be assholes. According to Parasite Eve lore, mitochondria are sentient beings, just waiting to re-emerge and assume control of humanity. Melissa Pearce was assumed to be the first human to be overtaken by such a possession, and transforms into Eve literally onstage during her opera performance.   

But why do we automatically assume that the mitochondria, if sentient, are dicks?  They might be really cool and friendly. If they’re really our little control centers, they could help us dance better, drive better, and make us stop being fat by making us dislike bad foods. They’d be our little microscopic socialist homies.