Study: Y-Chromosomal Adam Lived 208,300 Years Ago

Mitochondrial Eve is estimated to have lived between 99,000 and 200,000 years ago.   After all this time, she’s still sensitive about her age.

Dr Eran Elhaik from the University of Sheffield and his co-authors used conventional biological models to show that Y-chromosomal Adam is 8,300 years older than scientists originally believed. They put Y-chromosomal Adam within the time frame of the Mitochondrial Eve.

…The findings contradict a recent study – published in the American Journal of Human Genetics in February 2013 – which had claimed the human Y chromosome originated in a different species through interbreeding which dates Adam to be twice as old.

Source: Y-Chromosomal Adam Lived 208,300 Years Ago, Says New Study

How many “greats” would go before our shared grandfather?   The average generation time is about 25 years, so…208,300 divided by 25….  About 8,300 “greats”.

…and his name was probably one syllable.

Why don’t they just call him Mitochondrial Adam? Like Mitochondrial Eve…

Mitochondria are organelles (little functional units within our cells) that actually have their own DNA. When human offspring is conceived, only the mitochondrial DNA (mtDNA ) from the mother is passed down to the mitochondria of the offspring.This means that the DNA of the mitochondria in all of your body’s cells is maternally inherited. This fact makes it very useful to trace maternal lineages.

In contrast, Y chromosomes (a chromosome is a big bundle of DNA) are always paternally inherited. When egg and sperm meet prior to fertilization, the egg is always carrying an X chromosome, but the sperm could be carrying either an X or a Y chromosome.

Depending on which chromosome the sperm is carrying (X or Y) the offspring will be male or female. If the sperm carries X, then the fused zygote will have XX producing a female and if the sperm has Y then the fused zygote will be XY producing a male.

TLDR: Mitochondrial DNA is inherited through the female ancestral bloodline, while Y chromosomes are inherited through the male bloodline. You get to the common female ancestor through mtDNA, and to the common male ancestor through the Y chromosome.

The Irony…

…of calling them Adam and Eve, but they lived thousands of years before the Bible suggests.  It’s not that things in the Bible didn’t happen, but it’s an unreliable narrator – we’re finding gaps in time when comparing things like star position, tide implications and such.  But I digress…

Adam is too much of a misnomer. Not exactly the “first man” – why not call him Y-Chromosomal Genghis?

  1. There is still a lot of baggage with the name “Genghis” in many places in the world
  2. More people understand the concept of Adam than how Genghis Khan spread his DNA so successfully. And if they did, it brings us back to point #1 [obligatory Fight Club reference] because he raped his way across a continent…