eli5 How are so many ancestors possible?

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Posted elsewhere but would like explained like I’m 5.

What I can’t get my head around is: I had 2 parents, they had 4 (in total) who would have had 8 in a geometric progression, so going back even 1000 years or 20 generations (assuming an average lifespan of 50 years) is 2,097,152 ancestors for just me, and given that there is a reported 7.9 billion people on earth alive today it seems mathematically impossible that all those people could have existed.

In: 7

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Anonymous 0 Comments

People die. A lot. Like ALL the time. Before you’re done reading this reply, people died.

Humans have been around for couple hundreds of thousands of years. Probably been a few hundred billion people in those years; to put that in perspective, it would take you roughly 3 days to count to 1 million. It would take you 30+ years to count to 1 billion.

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