Meiosis to Mitosis - Evolution's unsolved riddle of the origins of sexual reproduction.

The one glaring gap in evolutionary theory that persists to baffle us is exactly how we went from asexual (meiosis) to sexual (mitosis) reproduction. There is many theories floating about in the scientific community but we have still not "nailed it down" definitively. I am studying evolution as a layman and I know the religious community loves to point out this "gap" in our current understanding. Of course a lack of understanding is not grounds to jump to conclusions in the form of automatically assigning supernatural causation- the God Did It complex. They have it so easy on the other side. If anyone else has delved into this subject I would be open to suggestions about various information sources to check out. I did find one location at a Xtian apologetics website where they discussed current secular theory on sexual reproductive origins. It was an interesting read because they stayed with the facts for the most part and left their own commentary to a minimum. It is astonishing that the individuals who contributed to the article have doctoral degrees but still cling to the "young earth creationist" theory. I verified this by emailing them as I was unsure at the time if they were really proponents of young earth theory. And I know it is irritating to even embellish notions of a young earth argument with the title of "theory."

Some of these sexual origin theories are no longer as popular as they once were. I believe the "red queen" theory is still looked at favorably. At any rate I find it all very engrossing and intriguing.

What will be the breakthrough that gives us the additional insight into just what happened a billion or so years ago that set the stage for sexual reproduction to gain a foothold and become the preferred way to ensure our DNA was being carried forward faithfully? Inquiring minds want to know.....

Views: 866

Reply to This

Replies to This Discussion

Hey Ed, this article looks a lot more convincing to me than that YEC page.


Evolutionary Origin of Recombination during Meiosis

Recent evidence indicates that meiosis arose very early in eukaryotic evolution, which suggests that essential features of meiosis were already present in the prokaryotic ancestors of eukaryotes. Furthermore, in extant organisms, proteins with central functions in meiosis are similar in sequence and function to key proteins in bacterial transformation. In particular, RecA recombinase—which performs the central functions of DNA homology search and strand exchange in bacterial transformation—has orthologs in eukaryotes that carry out similar functions in meiotic recombination. Both transformation and meiosis (including meiotic recombination) in eukaryotic microorganisms are induced by stressful conditions, such as overcrowding, resource depletion, and DNA-damaging conditions, suggesting that these processes are adaptations for dealing with stress. If such environmental stresses were a persistent challenge to the survival of early microorganisms, then continuity of selection through the prokaryote to eukaryote transition probably would have followed a course in which bacterial transformation naturally gave rise to the recombination process that is central to eukaryote meiosis.

Sounds reasonable to me.



© 2023   Created by Rebel.   Powered by

Badges  |  Report an Issue  |  Terms of Service