9) Emergence of nucleated cells

Paramecium: Image license Flickr Creative Commons

2 billion years ago, despite the enormous drag of its tidal seas the planet is still spinning fast. Each day – one revolution – lasts only about 18 hours. It is at this time that the first nucleated cell emerges. Tiny individual cells learn to cooperate and specialize within giant cell cooperatives. Perhaps this begins as one cell forces its way into another refusing to leave but eventually, some coalesce into symbiotic relationships with some parts making food and others moving the organism here and there. The individual parts become less independent but more secure as inseparable parts of the new wholes. Cooperatives!