Yes, we are all related to each other!! We know that we have 46 chromosomes that play a vital role in deciding who we become. A chromosome is just a tiny part of our DNA. DNA or Deoxyribo Neuclic Acid determines things like how we look, how much we sleep, and even how fast our food gets digested. These 46 chromosomes have mutated or changed so many times over the years that we can not find out our common ancestor at all. But there is a 47th chromosome and, it is in our mitochondria that is the powerhouse of the cell. It is called that because it produces all the energy we use.
This DNA is very unusual. It does not mutate. This DNA is passed on from your mother because the eggs carry the mitochondria and, the sperm doesn't. So, scientists have been able to trace this mitochondrial DNA to a single woman who lived about a hundred and fifty thousand years ago in Africa. It is said that many other women lived alongside her but, their lineage has gone extinct. Only her lineage has lived and, that is why she is called the mitochondrial eve.
So, the next time someone says that you are not related to them, just tell them that everyone shares a great great....... great grandmother.
So, we are just one big family living on the earth!