Adam and Eve

In 1987, the world was shocked by the announcement that the common ancestor of all humans’ mitochondria had been found- a woman that lived in Africa 200,000 years ago. Unfortunately, the general understanding of phylogenetics and coalescence was very low at the time, and this led to many misconceptions. Among these, many people mistakenly assumed that either a fossil had been discovered, or that only one single woman lived 200,000 years ago who was the mother of the human race- dubbed “Mitochondrial Eve”. Later, when scientists sequenced the Y chromosome from men, it was found that there was also a “Y-chromosome Adam”. This was sometimes seen as surprising too, especially when early estimates indicated that Y-chromosome Adam may never have met Mitochondrial Eve. Working together, collaboratively formulate a short post that explains...

1. Why Mitochondrial Eve should have been expected, and why the discovery of a Y-chromosome Adam was inevitable. What aspect of these particular loci ensures that a common ancestor could be inferred?
2. Would you expect either of those people to have been unusually lonely? Why or why not? (I'm actually not asking about their state of mind, but rather the size of the population in which they live!)
3. Furthermore, should you be surprised (or not) that there is a strong possibility that Mitochondrial Eve, the supposed Mother of the human race, never met Y-chromosome Adam?
4. Most importantly: Justify all of your answers to these questions using your knowledge of phylogenetics and coalescent theory.