Why did life start so early? Why did it stagnate in morphological structure for billions of years? Why were bacteria and archaea unaffected by environmental and ecological upheavals on a global scale? Why is all complex life monophyletic, arising just once in 4 billion years? Why do prokaryotes not continuously, or even occasionally, give rise to cells and organisms with greater complexity? Why do individual eukaryotic traits such as sex, the nucleus and phagocytosis not arise in bacteria or archaea? Why did eukaryotes accumulate all these traits?
