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Author Topic:   Why There Are Two Sexes
miosim
Member (Idle past 5677 days)
Posts: 57
From: NH, USA
Joined: 04-07-2007


Message 1 of 63 (445800)
01-03-2008 11:02 PM


I have no degree in Biology, but I would like to present the hypothesis about the two sexes emergence. I started working on this idea many years ago, but didn’t finish it, partially because I didn’t have much of opportunity to discuss it with experts. I sent it a couple of times to scientists, who in my opinion could’ve been interested, but the idea didn’t generate much of enthusiasm. The most comprehensive respond I received was as follows:
“ . There is a large amount of data that indicate that a process like what you describe is not happening in biological systems that are studied presently. Nobody would have necessarily stated that their data rule out a mechanism similar to what you propose because they wouldn't think about this possible mechanism.”
I would like to have a more specific objection to my hypothesis. Can someone point to these evidences? Or maybe someone knows the data that are in favor to this hypothesis and even could propose the experiment to falsify or to confirm this hypothesis. Any contribution will be greatly appreciated.
P.S.
Sorry for my grammatical and stylistical mistakes. Unfortunately, my 15 years old editor-in-chief is too busy with her own homework. Please let me know if something I am writing is unclear and needs corrections.
Thank you,
Mark Iosim
_________________________WHY THERE ARE TWO SEXES EXIST?_________________________
STRUGGLING WITH EXISTING PARADIGM
Years ago, I was curios about very general aspects of living systems development and even started my own investigation. Step by step the scope of my investigation was narrowing down and eventually it led me to a very controversial hypothesis about DNA molecule genetic activity that however may explain two sex’s existence.
The double strand DNA molecule contains one DNA strand inherited from the parental DNA strand and one newly synthesized. Both strands carry genetic information, however, according to my hypothesis, only one of them - newly synthesized strand is genetically active in the double stranded DNA molecule, while another strand is blocked from transcription. As a result, sister DNA molecules, emerging as result of single DNA autoreplication, while having identical genetic code, should have a dramatic difference in their genetic expression, because they have different newly synthesized DNA strands. Another word, according to this hypothesis, DNA autoreplication process always yields two sisters DNA molecules (and sister cells accordingly) of opposite complement types.
Unfortunately this hypothesis contradicts to one essential paradigm of molecular biology stating that in the most cases, sister DNA molecules must have identical genetic activity. Though, I could not understand how that paradigm was tested, i.e. how the genetic activity of single DNA molecules was determined. Even modern methods, are often unable to determine a single DNA molecule genetic activity. Instead, the cumulative genetic activity pattern of "DNA soup", consisting at least of thousands or even millions DNA molecules, is only tested. Despite a thorough literary search and discussions with experts in the field, I came upon an unexpected result: nobody could uncover any proofs for this paradigm, regardless of a general confidence in their existence.
THIS HYPOTHESYS IS DEAD ON ARRIVAL.
I have continued developing my controversial idea that seems to contradict not just a paradigm, but a common sense also, because our hypothetical cells have a limited access to its own genetic information. Yet, I may argue that a cell doesn't need genetic information itself, but the products of that information only. This is like a cake. You do not need to know the recipe to enjoy it. Genetic information serves as a recipe for cell products. If a cell has enough of them, it should not worry about the genetic recipe. For instance, our blood cells do not contain genetic information (nuclear DNA), but the necessary products only and the cells successfully maintain their living standards.
Regardless the limited access to some genetic recipes our hypothetical cells should have complete set of necessary genetic products, because cells may inherit them from a parental cell. The “pregnant” parental cell holds inside its boundary two sister cells that emerge as a result of DNA autoreplication process. The sister cells “cook” different (complement) dishes, but able freely share them while being inside the same boundary of a parental cell. These products, inherited by sister cells after separation, must provide them not only with a vital capacity, but also make them practically indistinguishable.
When parental ingredients become consumed, to survive our hypothetical cells have no choice, but auto-replicate again to refill missing genetic products. So, our hypothetical cells propagate, not because they are "worry" about future generations and survival of species, but because cells “worry” about they own vital capacity. Dependence of this cell on propagation must have forced their breeding that eventually, should cause the predominant spreading of these cells (compared to the cells, whose survival doesn't depend on autoreplication). Therefore, "our" cells may have been the main materials for evolutionary steps that followed i.e. they must have been the brick, which had been laid in foundation of the living Nature of our planet.
EMERGENCE OF TWO SEXES
It is well known that under conditions of low temperature or starvation, the cells cannot grow and auto-replicate themselves. Under this condition, our hypothetical cells must die after parental product’s depletion. This is not a speculation only. There are numerous observations (but no explanation) of massive cell deaths occurring during a long artificial block of cell auto-reproduction. To survive in this circumstance, the cells of opposite type can merge with each other and the resulting cell can generate a complete set of necessary genetic products and this way is capable of survival.
There is a striking similarity between the cells of our model and well-studied single-cell eukaryotic organisms. In their populations, each cell produces two sister cells of opposite type and as a result, the population consists of two type of cells. Under conditions preventing cell growth and auto-replication, the cells of opposite types merge to start the most ancient rituals, referred as the sexual process.
Based on this and other facts I came to a conclusion that sexual process emerged as a survival mechanism during unfavorable environmental conditions. In the beginning, cell merging was divorced from reproduction that emerged later. Eventually cell-merging process led to recombination of genetic material. During evolutionary stages that followed, recombination proved its advantage and has become more regular in character. However, even now we can often observe cell couples, who neglect their roles. These couples go through conjugation, but like a reminder of past times, they do not mix their genetic material and don't form a family (zygote).
In this post I covered a basic mechanism that may explain emergence of two sexes. This model may explain some other aspects of two sexes existence you can read about in my essay "WHY THERE ARE TWO SEXES EXIST?" home.earthlink.net/~miosim/.../why_there_are_two_sexes_essay.pdf
The most complete form of this hypothesis is "DNA Asymmetric Gene Activity”
http://home.earthlink.net/~miosim/.../dna_asymmetric_gene_activity.pdf
Edited by Adminnemooseus, : Changed topic title from "WHY THERE ARE TWO SEXES EXIST?" to "Why There Are Two Sexes". Could also have been "Why Two Sexes Exist". One way or the other, I'm getting rid of all those upper case letters (maybe I could sell them to Arachnophilia?).
Edited by miosim, : No reason given.
Edited by Adminnemooseus, : Shortened display form of two URL's, to restore page width to normal.

Replies to this message:
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Adminnemooseus
Administrator
Posts: 3974
Joined: 09-26-2002


Message 2 of 63 (445807)
01-03-2008 11:35 PM


Thread moved here from the Proposed New Topics forum.

  
Adminnemooseus
Administrator
Posts: 3974
Joined: 09-26-2002


Message 3 of 63 (446359)
01-05-2008 9:26 PM


Thread moved here from the Miscellaneous Topics in Creation/Evolution forum.
{Added by edit: The topic originator contacted be by e-mail and suggested that the "Biological Evolution" forum is a better place for this topic.
I agree. - Adminnemooseus}
Edited by Adminnemooseus, : See above.

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 4 of 63 (446365)
01-05-2008 9:51 PM
Reply to: Message 1 by miosim
01-03-2008 11:02 PM


and
why aren't there several sexes?
Enjoy.

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This message is a reply to:
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Replies to this message:
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molbiogirl
Member (Idle past 2641 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 5 of 63 (446368)
01-05-2008 10:00 PM
Reply to: Message 4 by RAZD
01-05-2008 9:51 PM


Re: and
Well. Genetically speaking, there are.

This message is a reply to:
 Message 4 by RAZD, posted 01-05-2008 9:51 PM RAZD has replied

Replies to this message:
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RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 6 of 63 (446369)
01-05-2008 10:10 PM
Reply to: Message 5 by molbiogirl
01-05-2008 10:00 PM


Re: and
shhh ... (don't spoil the fun)
Edited by RAZD, : fun

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miosim
Member (Idle past 5677 days)
Posts: 57
From: NH, USA
Joined: 04-07-2007


Message 7 of 63 (446377)
01-06-2008 12:13 AM
Reply to: Message 5 by molbiogirl
01-05-2008 10:00 PM


Re: and
molbiogirl:
Well. Genetically speaking, there are.
molbiogirl,
Can you please collaborate on this, even it would spoil fun for RUSD.

This message is a reply to:
 Message 5 by molbiogirl, posted 01-05-2008 10:00 PM molbiogirl has replied

Replies to this message:
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molbiogirl
Member (Idle past 2641 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 8 of 63 (446390)
01-06-2008 1:26 AM
Reply to: Message 7 by miosim
01-06-2008 12:13 AM


Re: and
Sorry, RUSD! The jig is up.
(Miosm, it's RAZD ... Rebel American Zen Deist)
M, I don't suppose you've had Intro Genetics.
You seem to think that XX = F and XY = M.
But that's not entirely true.
Female
XX normal
XO Turner 1:3000
XXX Triple-X 1:1000
XXXX No name 1:???
XXXXX No name 1:???
Male
XY normal
XXY Klinefelter 1:500
XXXY No name 1:???
XYY "Supermale" 1:900
XXYY "Supermale" 1:???
I would imagine there is an XXXXY too. And possibly other variations (XXXYY, XXYYY, etc.).

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Replies to this message:
 Message 9 by Taz, posted 01-06-2008 2:01 AM molbiogirl has replied
 Message 10 by arachnophilia, posted 01-06-2008 2:14 AM molbiogirl has replied

  
Taz
Member (Idle past 3291 days)
Posts: 5069
From: Zerus
Joined: 07-18-2006


Message 9 of 63 (446393)
01-06-2008 2:01 AM
Reply to: Message 8 by molbiogirl
01-06-2008 1:26 AM


Re: and
Oh come on! Those are abnormalities.

This message is a reply to:
 Message 8 by molbiogirl, posted 01-06-2008 1:26 AM molbiogirl has replied

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arachnophilia
Member (Idle past 1343 days)
Posts: 9069
From: god's waiting room
Joined: 05-21-2004


Message 10 of 63 (446396)
01-06-2008 2:14 AM
Reply to: Message 8 by molbiogirl
01-06-2008 1:26 AM


you forgot a few
the naturally occuring X0 males, as in insects, and the whole gamut of Z's and W's.


This message is a reply to:
 Message 8 by molbiogirl, posted 01-06-2008 1:26 AM molbiogirl has replied

Replies to this message:
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molbiogirl
Member (Idle past 2641 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 11 of 63 (446398)
01-06-2008 4:11 AM
Reply to: Message 9 by Taz
01-06-2008 2:01 AM


Re: and
Well, yes, Taz, they are abnormalities.
But some of them don't appear abnormal.
The "metafemales" are only slightly below average in intelligence.
Most Klinefelters are normal enough to pass unnoticed in society.
As are the "metamales". In fact, most "metamales" don't even know they have the extra chromosomes.

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molbiogirl
Member (Idle past 2641 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 12 of 63 (446399)
01-06-2008 4:12 AM
Reply to: Message 10 by arachnophilia
01-06-2008 2:14 AM


Re: you forgot a few
Thanks, Arach. I didn't forget. I limited it to humans since I thought that was what his OP was referring to.
Edited by molbiogirl, : sp

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Replies to this message:
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arachnophilia
Member (Idle past 1343 days)
Posts: 9069
From: god's waiting room
Joined: 05-21-2004


Message 13 of 63 (446400)
01-06-2008 4:20 AM
Reply to: Message 12 by molbiogirl
01-06-2008 4:12 AM


Re: you forgot a few
ah. well, i had assumed otherwise, since the emergence of this particular kind of sexual reproduction is far older than humanity. but then again, creationists might not be aware of that sort of thing, right?


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miosim
Member (Idle past 5677 days)
Posts: 57
From: NH, USA
Joined: 04-07-2007


Message 14 of 63 (446407)
01-06-2008 8:35 AM
Reply to: Message 12 by molbiogirl
01-06-2008 4:12 AM


molbiogirl,
Indeed I didn’t have Intro Genetics and therefore I am trying to use any opportunity to fill the gaps. I thought you are referring to a weird cases where more than one cell merge together for reproduction. But I do not want to go into this area, especially if it isn’t what you meant.
The phenomenon you described belongs to sex determination mechanism that actually depends not only on X or Y chromosomes, but on autosomes abnormality also. I briefly mentioned this phenomenon in my essay as follow:
“ . According to the chromosome theory an infant’s sex is definitely determined by a distinct sex-chromosome pair when the women’s X-chromosome joins with the man’s X- or Y-chromosomes. Depending on the combination XX or XY, parents will joy a girl or a boy. This theory has been proved by a good deal of fact, but there are number of examples, which are exceptions of this rule. For instance, the genetic factors of sex in plants often depend upon surrounding conditions and in some animals (for example media Crenomytilus grayanus dunker) depends on age. Experiments on fruit flies revealed that not only sex chromosomes, but also other chromosomes could determine sex, independently from the zygote’s sexual constitution. Another very important factor for sexual differentiation are hormones. By injecting female hormone into a chicken embryo, it is forced to become a female, even by its chromosomal constitution it was destined to become a male. When it hatches, this artificial female cannot be distinguished from an ordinary, "normal" female.
In the beginning of 20th century, the idea of organism bio-potentiality was formulated. According to this idea, an organism has inclinations for both, male and female sexes, and determination of sex occurs during development. For example, in the beginning stages of embryo development, human gonads of both sexes are non-distinguishable. Such gonads contain two main structures - cortex and medulla. During development of male embryos, the cortex degenerates, and the medulla forms a testicle. In female embryos, a medulla degenerates, and the cortex forms an ovary.
Based on the idea of bio-potentiality and employing our model, we can build a speculate scenario of the organism sex development. The main roles are cast between "patriarchal" and "matriarchal" cells that determine male and female properties of an organism ..............”
molbiogirl:
I limited it to humans since I thought that was what his OP was referring to.
The main concept is not as sexy, as it appears from the title of this thread. It isn't about sex in humans, it is rather about sex in microbes. Actually the main mechanism I am proposing in my hypothesis is the cell differentiation mechanism, in which sex is just only one specific case of this differentiation. Of cause, I tried to extend this hypothesis into development of human sex also, but it isn’t in my OP. My OP is intended just to comply with the requirement for OP to be short and specific. For actual discussion, I expect, that at least the essay
http://home.earthlink.net/~miosim/sitebuildercontent/... will be read.
For reader having background in Biology or who interested in Molecular Biology I would recommend to read the more formal version of this hypothesis.
http://home.earthlink.net/~miosim/sitebuildercontent/...
___________________________________________________________________
RASD, having fun yet?
I did some homework and look over your essay “Sexual Selection, Stasis, Run-away Selection, Dimorphism and Human Evolution”. This is outside of my interests, but you may be interested to read about research of Vigen Geodakyan
Vigen Geodakyan
He developed a very elegant theory about distribution of evolutionary roles: for a male to "design and test" of new varieties and for a female, to “save the best”.
Have a fun.
Edited by miosim, : No reason given.
Edited by Adminnemooseus, : Shortened display form of two (same?) URL's, to restore page width to normal.

This message is a reply to:
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Replies to this message:
 Message 15 by RAZD, posted 01-06-2008 9:32 AM miosim has replied

  
RAZD
Member (Idle past 1405 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 15 of 63 (446414)
01-06-2008 9:32 AM
Reply to: Message 14 by miosim
01-06-2008 8:35 AM


RASD, having fun yet?
Most definitely, miosim. Figured the name out yet?
This is outside of my interests, but you may be interested to read about research of Vigen Geodakyan
Vigen Geodakyan
He developed a very elegant theory about distribution of evolutionary roles: for a male to "design and test" of new varieties and for a female, to “save the best”.
I didn't see anything elegant in that paper, and your description is still just female selection, seeing as males cannot intentionally develop (design) more variation.
The paper also seems to make several false divisions of things into two camps when there can be a lot of overlap (eg - right-handed vs left-handed ignores all levels of ambidextrous individuals). Sometimes a spectrum is a better concept. Something that can also apply to the development of cell differentiation.
The main concept is not as sexy, as it appears from the title of this thread. It isn't about sex in humans, it is rather about sex in microbes. Actually the main mechanism I am proposing in my hypothesis is the cell differentiation mechanism, in which sex is just only one specific case of this differentiation.
Sex in asexual microbes of sex in sexual microbes? Again there are several organisms where there are more than two sexes. Why use sex if you want to talk about differentiation (doesn't that just confuse the issue)?
http://home.earthlink.net/~miosim/sitebuildercontent/... will be read.
For reader having background in Biology or who interested in Molecular Biology I would recommend to read the more formal version of this hypothesis.
http://home.earthlink.net/~miosim/sitebuildercontent/...
Am I missing something? They seem to be the same essay. Same as in the OP too.
For instance, the genetic factors of sex in plants often depend upon surrounding conditions and in some animals (for example media Crenomytilus grayanus dunker) depends on age.
And the sex of alligators is determined by heat in the nest.
Another very important factor for sexual differentiation are hormones. By injecting female hormone into a chicken embryo, it is forced to become a female, ...
And a human male that does not produce testosterone will grow up looking like a female except the internal sex organs will be male.
Meanwhile snails are bisexual androgynous hermaphrodites.
Enjoy.
Edited by RAZD, : snails tales
Edited by Adminnemooseus, : Shortened display form of two quoted (same?) URL's, to restore page width to normal.

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we are limited in our ability to understand
by our ability to understand
RebelAAmericanOZen[Deist
... to learn ... to think ... to live ... to laugh ...
to share.

This message is a reply to:
 Message 14 by miosim, posted 01-06-2008 8:35 AM miosim has replied

Replies to this message:
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