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Author Topic:   The Evolution of sex
halucigenia
Inactive Member


Message 5 of 28 (281751)
01-26-2006 12:42 PM
Reply to: Message 1 by beanhead
08-28-2003 12:47 AM


Yes sex evolved long long ago
As mark24 said long before gymnosperms 'sexual' plants appeared, if this is what this thread is actually about. My favourite revelation in biology class was that pteridophytes and bryophytes (ferns and mosses) actually produce mobile, flagellate sperm that fertilizes an egg in their sexual reproduction, just like us animals.
So our shared common 'sexual' ancestor was indeed a long long time ago.

This message is a reply to:
 Message 1 by beanhead, posted 08-28-2003 12:47 AM beanhead has not replied

Replies to this message:
 Message 23 by Brad McFall, posted 02-03-2006 7:09 AM halucigenia has not replied

  
halucigenia
Inactive Member


Message 7 of 28 (281924)
01-27-2006 4:00 AM
Reply to: Message 6 by Brad McFall
01-26-2006 6:09 PM


Haploid and diploid phase phenotypes
quote:
see how I will try to show that sex is matter of difference of 1-Dimensionality purely
you are going to have to explain a lot just for me to decipher what you are even trying to get at here (as usual Brad). That may be off topic but we will see where this thread goes.
quote:
The neat thing about ferns' sex is that I think some graphs about the different gene frequencies in haploids vs. diploids might indicate via the 1-D affects actual phenotype differences(not charms) of the heart shaped form which water mediates fusion of the different kinds of gametes in these plants.
Is there a problem with haploid and diploid phases of an organism expressing different phenotypes? Another interesting topic I had not thought of this before.
I was just amazed when I learned that plants had sperm

This message is a reply to:
 Message 6 by Brad McFall, posted 01-26-2006 6:09 PM Brad McFall has replied

Replies to this message:
 Message 8 by Brad McFall, posted 01-27-2006 12:58 PM halucigenia has replied
 Message 10 by mark24, posted 01-28-2006 7:56 PM halucigenia has replied

  
halucigenia
Inactive Member


Message 11 of 28 (282339)
01-29-2006 3:42 PM
Reply to: Message 10 by mark24
01-28-2006 7:56 PM


Re: Haploid and diploid phase phenotypes
Is that a comment about punctuation, or am I not to hold my breath for an explanation?
I do, eventually, want to understand just one of Brad's posts

This message is a reply to:
 Message 10 by mark24, posted 01-28-2006 7:56 PM mark24 has not replied

  
halucigenia
Inactive Member


Message 12 of 28 (282345)
01-29-2006 4:39 PM
Reply to: Message 8 by Brad McFall
01-27-2006 12:58 PM


Re: Haploid and diploid phase phenotypes
I have had some time to think about this Brad, and now I think that I understand, please tell me if I am anywhere close to your way of thinking.
The multicellular haploid adult form of the fern is a graph/set of the multicellular diploid adult form in the way that a mandlebrot set is a graph/set of the julia sets that it contains?
If you could graph the 1-D symmetry (fractal dimension) of the prothallus as a complex plane, then the distance between any two given gametes, wether on the same prothallus or not, would indicate the symmetry of the resulting multicellular diploid adult form?
I like fractals, and have had some success in generating fern-like and cell-like fractals using iterative algorithms. I have always thought that cellular development could be explained by fractal geometry.

This message is a reply to:
 Message 8 by Brad McFall, posted 01-27-2006 12:58 PM Brad McFall has replied

Replies to this message:
 Message 13 by Brad McFall, posted 01-29-2006 5:25 PM halucigenia has replied

  
halucigenia
Inactive Member


Message 14 of 28 (282385)
01-29-2006 8:34 PM
Reply to: Message 13 by Brad McFall
01-29-2006 5:25 PM


Re: Haploid and diploid phase phenotypes
If the the haploid form IS just the diploid form differentially sexualized then the differentialisation is only sexual in the fact that the gametes are formalised as the water flow descends across the prothallus thus dimentionalising haploid form. If the MOTILE sperm tend to give non random directions, does this not invalidate the starting point and therefore disrupt the non deterministic outome of the chaiotic attractor of the complex plane?

This message is a reply to:
 Message 13 by Brad McFall, posted 01-29-2006 5:25 PM Brad McFall has replied

Replies to this message:
 Message 15 by macaroniandcheese, posted 01-29-2006 8:47 PM halucigenia has replied
 Message 16 by RAZD, posted 01-29-2006 8:54 PM halucigenia has not replied
 Message 17 by Brad McFall, posted 01-30-2006 8:48 AM halucigenia has replied
 Message 26 by Brad McFall, posted 02-04-2006 10:48 AM halucigenia has replied

  
halucigenia
Inactive Member


Message 18 of 28 (282911)
01-31-2006 2:10 PM
Reply to: Message 15 by macaroniandcheese
01-29-2006 8:47 PM


Re: Haploid and diploid phase phenotypes
quote:
how are our haploid reproductive cells different than the haploid phase of moss etc? and thus wouldn't that make them the important phase and us just carriers or something?
  —brennakimi
The haploid phase of mosses and ferns have an adult phenotype separate from the adult phenotype of the diploid phase. In this life cycle we can assume that evolution is a factor in the morphology of the haploid phenotype as well as the diploid phenotype, therefore the haploid phenotype is as 'important' in the evolution of such organisms as the diploid form is in ours.
I can't see how evolution could influence our haploid form as much as it could influence an adult haploid form that exists separately from the diploid form, as in ferns and mosses.
Anyway I get your point, I think, let's call it the selfish haploid hypothesis?

This message is a reply to:
 Message 15 by macaroniandcheese, posted 01-29-2006 8:47 PM macaroniandcheese has replied

Replies to this message:
 Message 20 by macaroniandcheese, posted 01-31-2006 6:19 PM halucigenia has replied

  
halucigenia
Inactive Member


Message 19 of 28 (282960)
01-31-2006 6:10 PM
Reply to: Message 17 by Brad McFall
01-30-2006 8:48 AM


Re: Haploid and diploid phase phenotypes
The question of the sperm's motility was not meant to refute your hypothesis about dimentionality, but the graphing of the sperm due to the water flow. Surely the direction of approach is not as important as the spatial relationship between the location of the origination of the sperm and the site of the egg, even given the fact that the fertilisation takes place on a prothallus of a different individual, even though self fertilisation is not ruled out entirely. The symmetry question is entirely of the morphology of the prothallus I would have thought, not the sperm anatomy (though I can see the the symmetry of the sperm would affect its path towards the egg, though I can't see how this would be significant).
I don't think that water has a randomisation force, unless you are thinking Brownian motion effects?
Anyway, the non-determenistic nature of chaotic attractor of the complex plane certainly could be affected by a directed motion of a motile sperm towards the egg.
In a 1D symetry, or a symmetry greater than 1D, but less then 2D, (fractal dimension) the symmetry should certainly be independant of directionality of the motile sperm.
Gametic unions in the phase space of the prothallus, if they are non determenistic, should not be a precursor to the form of sexuality, even if expressed by different chromosomes IMO.
Let's hope that this communication is not lost as readily as the first mark on a blackboard.

This message is a reply to:
 Message 17 by Brad McFall, posted 01-30-2006 8:48 AM Brad McFall has not replied

  
halucigenia
Inactive Member


Message 21 of 28 (282973)
01-31-2006 6:50 PM
Reply to: Message 20 by macaroniandcheese
01-31-2006 6:19 PM


Re: Haploid and diploid phase phenotypes
quote:
precisely what i was thinking. i need to reread my margulis.
I was alluding to Dawkins.

This message is a reply to:
 Message 20 by macaroniandcheese, posted 01-31-2006 6:19 PM macaroniandcheese has replied

Replies to this message:
 Message 22 by macaroniandcheese, posted 01-31-2006 11:11 PM halucigenia has not replied

  
halucigenia
Inactive Member


Message 27 of 28 (287379)
02-16-2006 3:53 PM
Reply to: Message 26 by Brad McFall
02-04-2006 10:48 AM


Brad asks me what I am on about
Formalised in the way of creating a formal system capturing the essential features of the real world in a conceptual mathematical system. That is if, sexuality is remandable in a mathematical system at all, though I can't see how, which was my point. I am not alluding to formal and informal logical expressions at all. As for a changable attitude being remandable, I take it that you mean the directional attitude of the gemete and not my 'attitude' towards this intermittant discussion

This message is a reply to:
 Message 26 by Brad McFall, posted 02-04-2006 10:48 AM Brad McFall has replied

Replies to this message:
 Message 28 by Brad McFall, posted 05-14-2006 9:29 PM halucigenia has not replied

  
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