Most people,
despite their religious affiliation or lack thereof, know the general idea of the story of Adam and Eve from Christianity,
they are said to be the first man and woman created by god, well geneticists
use these popular terms for labeling the first X and Y chromosome of the human
species when using genetic analysis to date them. Recently a new study by Eran Elhaik from the University of Sheffield was published in the European
Journal of Human Genetics giving a new approximation of the “Y-chromosome
Adam”. The new date for when the first male with the Adam chromosome lived is
208,000 years ago, only 8000 years prior to when Homo sapiens are estimated to
have risen, via fossil data.
About a year ago a study
was released that placed “Adam” to have been living approximately 33800 years
ago, right around the same time frame that Neanderthals are genetically
sequenced, via fossil records, to have appeared. Elhaik noticed how this study
implied that the Y-chromosome would have to predate all anatomical modern
humans, meaning there was a abundant amount of interbreeding between the variations
of human species living at the same time, rather than the odd accounts that had
been speculated. Yet, there is very little fossil record in behalf of this old
study, Elhaik deemed this to be the result of poor data analysis and stated
that the study was disastrous since it placed the oldest member of Homo sapiens
prior to when the species had come to be: he referred to this poor study as
folly due to a “space-time paradox”, which prompted him to repeat the study
himself.
A person is composed of
their parents’ chromosomes, an XY from the father and an XX from the mother;
the Y chromosome is attributed to male characteristics and other sex dependent connotations,
it is, normally, only given to males this is the reasoning for receiving the
male character’s name from the biblical story. Meanwhile the X-chromosome,
which can be given by both parents, is called the mitochondrial genome for one
of the X-chromosomes from the mother is always given to the offspring, so the
name the common ancestor of the X-chromosome to Homo sapiens is given is the “mitochondrial
Eve”, falling in suit with the biblical story line. “Mitochondrial Eve” is
actually supported by the fossil record and placed at a very similar time frame
to the “Adam chromosome”, she is a at a fairly definite 208,300 years ago.
So although it does seem
that the “Adam” and “Eve” of our species did appear around the same time frame,
based on genetic analysis of the fossil records, it also seems they were a bit
older than the creation date given by Christianity… which is about 14,800 years
too young actually and the land was more than likely no garden of Eden.
Nicole Peterkin (3)
The biblical reference can confuse some, but is there a better option that still gets the point across?
ReplyDeleteIts really interesting to think that the human population was at one time small enough to have there be an identifiable "Adam" and "Eve". This is the same reason that there is larger genetic variation in some troops of chimpanzees than in the entirety of the human race. Its an unsettling though that in comparison to most other species on the planet Homo sapiens is almost entirely inbred.
-Stephen O'Brien
It is interesting the ways in which human kind can be approximated to a certain point of an X and Y chromosome appearance. Even more intriguing is both individuals are approximated to have existed around the same time. Of course this is based upon fossil data, which could mean that Adam and Eve could be even closer approximation. This information does not seem to invalidate the claim of Christians, which is that Adam and Eve existed, for the estimation is not isolated to 14,800 years, but in fact many Christians think Adam and Eve existed at much before this estimate. Overall, what a truly great and thought provoking study!
ReplyDeletePosted by Michael Dailing.
Sorry for the confusion, the goal of this topic was not to spark a religious debate or denounce their beliefs, but merely because the naming method of the chromosomes I used light banter to tie the source of the naming to the time frame. There was no doubt a first of our species, in both sexes, at some point in time, but the correct time frame was all that was in question, which was more accurately placed by Elhaik's study.
DeleteNicole Peterkin
This comment has been removed by the author.
ReplyDeleteI'm still a little uncertain of what the overall message here is. Did the paper claim to find the source of the first Y chromosome? I have read about "Mitochondrial Eve" as the common ancestor of all modern humans, but what is the source of our Y chromosome?
ReplyDeletePosted by Tim Daly
Yes, the study done by Elhaik was to correctly identify the time frame of when the mutation to the Y chromosome that our species is known and identified by happened. I guess I really didn't acknowledge the fact that Neanderthals and homo sapiens have different chromosome structures in my sum up; I'll definitely try to be more clear next time. thank you.
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