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Author Topic:   Problems with Mutation and the Evolution of the Sexes
bluegenes
Member (Idle past 558 days)
Posts: 3119
From: U.K.
Joined: 01-24-2007


Message 91 of 180 (458993)
03-03-2008 8:30 AM
Reply to: Message 89 by CTD
03-03-2008 7:23 AM


CTD writes:

Now it's time to reassess the value of time spent participating on this forum, where half of what I say is intentionally misportrayed and truth is unwelcome. (See msg #52, for just one lame example. I'll not waste more time responding.)

All you need to do, if you disagree with anything in Message 52 is quote the relevant bits, and explain why. I'll be happy to explain and defend any of my comments in that message.

As for unwelcome truths, do repeat and expand on any "truths" you feel you've come up with. If you mean the kind of thing that I originally took you up on, which was this:

CTD writes:

Greetings, Lyston. As you can see, evolutionism is still as bankrupt as ever on this topic, and no serious attempt to tackle it is likely to be forthcoming.

I'm happy to discuss whether any serious attempts to tackle the origins and evolution of sexual reproduction are being made in relation to any research either of us can find. You haven't actually backed your assertion at all, and I'm sure that I won't be the only person reading the thread who suspects that your decision not to continue on this vein is actually nothing to do with your views being misrepresented, but rather, the opposite.


This message is a reply to:
 Message 89 by CTD, posted 03-03-2008 7:23 AM CTD has not yet responded

  
molbiogirl
Member (Idle past 723 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 92 of 180 (459025)
03-03-2008 11:36 AM
Reply to: Message 77 by Lyston
03-03-2008 1:11 AM


That would be human sexual reproduction. I can't say I know for sure, but I am sure that asexual reproductive organisms don't combine two cells, especially when they themselves are one cell.

There are 2 kinds of reproduction: sexual and asexual.

Asexual reproduction: Formation of new individuals from a single individual without the involvement of gametes.

Sexual reproduction: Process in which two cells, termed gametes, come together to form one fertilized cell that contains genetic information from both parental cells.

Science uses precise terminology. "Sexual" reproduction is not a general term that covers both asexual and sexual.

Genders, defined by male, female, hermaphrodite, or none at all (can't think of the name), are something I'm interested in.

Wrong.

Gender refers to behaviors and cultural definitions of what "belongs" to one or both sexes.

To repeat:

Gender: The behavioral, cultural, or psychological traits typically associated with one sex.

Sex refers to male and female.

Sexual reproduction, the process in which an organism or organisms create more of the said organism, is something I'm not interested in.

Funny. Your entire OP deals with the origin of the 2 sexes.

Lyston in the OP writes:

But here's where we run into a snag. When does the self replicating stop? If something mutates into something that can't self replicate, what happens? Something turns into a guy and is ready to start the mating process... but he has no mate. He's a mutation, a rare mutation that happens every so often.

Evolution tells us that not only did something evolve into a guy, but at the SAME time and SAME place, a thing of the SAME species evolved into an organism that perfectly matched as an opposite of the male, aka a female.

And again, in the post I am responding to:

How did it start becoming a male or female?

That is "the origin of sexual reproduction".

When debating "the origin of sexual reproduction" in a scientific forum, you need to be willing to discuss the topic using scientific terminology and ideas.

Gender is generally the purvue of sociology and psychology.

Not the ToE.

Should you wish to continue a discussion of gender, I suggest you start a new thread.


This message is a reply to:
 Message 77 by Lyston, posted 03-03-2008 1:11 AM Lyston has responded

Replies to this message:
 Message 101 by Lyston, posted 03-03-2008 8:09 PM molbiogirl has responded

  
molbiogirl
Member (Idle past 723 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 93 of 180 (459028)
03-03-2008 11:41 AM
Reply to: Message 78 by Lyston
03-03-2008 1:17 AM


This is not an evolution thread?

No. This is not a ToE thread. This is a mutation and sexual reproduction thread.

It was placed here based on your OP.

If you have any quibbles with placement, Admin would be happy to reconsider its placement. Just post a note in Message 1.

Who is Jeebus, and when did I bring his pals into my thread?

We do not discuss gods in the science forums.

Should you wish to discuss faith based nonsense, please take your comments to the appropriate thread.


This message is a reply to:
 Message 78 by Lyston, posted 03-03-2008 1:17 AM Lyston has responded

Replies to this message:
 Message 94 by Admin, posted 03-03-2008 12:11 PM molbiogirl has responded
 Message 102 by Lyston, posted 03-03-2008 8:11 PM molbiogirl has not yet responded

  
Admin
Director
Posts: 12580
From: EvC Forum
Joined: 06-14-2002
Member Rating: 3.3


Message 94 of 180 (459032)
03-03-2008 12:11 PM
Reply to: Message 93 by molbiogirl
03-03-2008 11:41 AM


molbiogirl writes:

No. This is not a ToE thread. This is a mutation and sexual reproduction thread.

Lyston is interested in the evolutionary explanation for the origin of the two sexes, what we would normally call sexual reproduction.

We do not discuss gods in the science forums.

True, but...

Should you wish to discuss faith based nonsense...

...maybe a bit of a softer touch?


--Percy
EvC Forum Director

This message is a reply to:
 Message 93 by molbiogirl, posted 03-03-2008 11:41 AM molbiogirl has responded

Replies to this message:
 Message 95 by molbiogirl, posted 03-03-2008 12:52 PM Admin has not yet responded

    
molbiogirl
Member (Idle past 723 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 95 of 180 (459040)
03-03-2008 12:52 PM
Reply to: Message 94 by Admin
03-03-2008 12:11 PM


Lyston is interested in the evolutionary explanation for the origin of the two sexes, what we would normally call sexual reproduction.

Absolutely.

However. S/he keeps discussing the ToE in general, as a theory.

There are plenty of threads for that.

Not here. Yes?


This message is a reply to:
 Message 94 by Admin, posted 03-03-2008 12:11 PM Admin has not yet responded

  
FliesOnly
Member (Idle past 2226 days)
Posts: 797
From: Michigan
Joined: 12-01-2003


Message 96 of 180 (459041)
03-03-2008 12:55 PM
Reply to: Message 51 by CTD
03-01-2008 12:14 AM


CTD writes:

BTW, shouldn't the 'ancestors' of mammals be portrayed with fur?

Your level of ignorance is stunning. The last time I checked birds are not mammals.

We are Synapsids (dimetrodons, by the way, are not dinosaurs).
Dinosaurs (and birds) were/are Diapsids.


This message is a reply to:
 Message 51 by CTD, posted 03-01-2008 12:14 AM CTD has not yet responded

  
molbiogirl
Member (Idle past 723 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 97 of 180 (459043)
03-03-2008 1:09 PM
Reply to: Message 77 by Lyston
03-03-2008 1:11 AM


Let's start over.

Maybe it could be seen better as I'm interested in the creation organs that make up a gender. How did something (that is either a hermaphrodite or something else) start to form the separate organs penis and vagina? How did it start becoming a male or female?

This is NOT evolution: A critter of a species without a penis/vagina gives birth to a critter with a fully formed penis/vagina.

btw. You do realize, of course, that neither a penis nor a vagina is necessary for sexual reproduction?

Sexual reproduction merely requires an exchange of genetic info between 2 organisms. (See also: Quetzal's example of bacterial genetic exchange, below.)

This IS evolution:

Quetzal in Message 33 writes:

The origin and maintenance of sexual reproduction is an area of active research. That means that the question has not been satisfactorily answered as yet (i.e., no concensus has developed). One of the problems is that sexual reproduction – or something resembling it – apparently evolved way down at the base of the organismal tree. For instance there are several haloarchea (eg., Halorubrum) which use recombination – i.e., sexual reproduction – in the full sense of the word. There are also several single-celled eukaryotes that also use actual recombination (such as Plasmodium) during reproduction. Finally, in one sense bacterial conjugation – where genetic material is transferred between one type of bacteria and another via an exchange of plasmids – can be considered a different form of “sexual reproduction” that evolved in a completely different domain of life. In other words, not only is sexual reproduction not limited to modern multi-celled organisms, but it apparently started evolving very shortly after life itself appeared.

So how did all the hanky-panky get started? There are several reasonable hypotheses (Catholic Scientist provided a wiki quote covering a number of them way back in message 5 – to which I notice you didn’t bother to reply). In general, the hypotheses can be divided into genetic and ecological explanations. CS’s wiki quote covered most of the genetic ones – if you have any questions on those, I’ll try and answer them although I’m far from an expert in genetics.

I personally prefer the ecological approach. Not, I hasten to add, because the answer is intrinsically better than the more purely genetic approaches, but rather because from training and experience I have a tendency (my friends sometimes say “a purblind determination” ) to view most questions in biology in that light. The most compelling of these explanations derive from an application of what is known as the Red Queen Hypothesis (with a tip o’ the hat to Matt Ridley, who first applied the term from its broader meaning to the specific case of sexual reproduction). For those of you who are unfamiliar with the term, it derives from Louis Carroll’s wonderful book Through the Looking Glass, where Alice met the Red Queen who said, “In here, it takes all the running you can do to stay in the same place.” In essence, it is a description of the co-evolutionary arms race between a predator and its prey (or a parasite and its host). In this race, the key selection pressure on each population is its counterpart in the relationship. Simplistically, as a f’rinstance, as a predator becomes more successful in catching and killing it’s prey, the prey population may suffer a decline to a point where rare individuals with a more effective strategy or physical ability to escape come to predominate (i.e., the population is said to have adapted to the new capability of its predator), thus leading to a decline in the predator population until a more successful strategy or physical ability comes to predominate, and so the cycle begins anew. Obviously there are limitations on how far this co-evolution can continue, primarily because the predator-prey relationship isn’t the only selection pressure on the two populations. Eventually something resembling an equilibrium is likely to develop, although there will continue to be fluctuations around this equilibrium.

One of the really interesting aspects of the Red Queen, and how I see it applying to the evolution of sex, is the parasite-host relationship (this isn’t the hypothesis’ only possible application to the question, but I think it is one of the easiest to illustrate, and has the advantage of having some good studies to back it up). Take a hypothetical population of clonal organisms with genotype A. If a parasite manages to infect this genotype, it will by definition be able to infect every single individual carrying the genotype. Because they’re clonal, the only thing the organisms in this case can do is to wait for the really rare beneficial mutation to appear in its lineage. Since the particular mutation may or may not appear, the population may be doomed to extinction. Let’s say the mutation DID appear, creating genotype B for instance, now we have type A in serious decline due to its parasite load in comparison to B (which for the moment is running around parasite-free). As A declines, its parasite also declines, creating selection pressure for it to adapt to the now dominant type B. If/when it does, B starts declining, A is already infected and in decline, so the clones have to come up with a genotype C, putting pressure on the parasite to adapt to C, and the Red Queen rollercoaster is well and truly underway.

Now, what happens if our host population is capable of throwing up variation much faster than the parasite can? Maybe even in a single generation? Well, the parasite is now in serious trouble. This is what recombination through sexual reproduction does. It is a much faster way of creating variation than waiting around for a lucky mutation. Beginning with a simple exchange of genetic material (i.e., as in bacterial combination), as organisms and their parasites got more complex – and the inter-relations between them got more complex – the Red Queen refined the simple exchange of genetic material into something more closely resembling actual sexual reproduction. From there, it’s only a matter of continuing to refine this adaptation to where in some species we now have two genders.

Others have provided links.

Message 5
Message 9
Message 30
Message 60

Please take the time to educate yourself.
Should you have any questions after you have read the links, we would be more than happy to answer them.

Edited by molbiogirl, : No reason given.


This message is a reply to:
 Message 77 by Lyston, posted 03-03-2008 1:11 AM Lyston has responded

Replies to this message:
 Message 104 by Lyston, posted 03-03-2008 8:54 PM molbiogirl has responded

  
Lyston
Member (Idle past 3906 days)
Posts: 64
From: Anon
Joined: 02-27-2008


Message 98 of 180 (459090)
03-03-2008 7:17 PM
Reply to: Message 86 by Dr Adequate
03-03-2008 2:14 AM


thank you for that. First time someone posted something directly related to the topic (not the changed title). I just wanted a plausible theory on genders, not sexual reproduction.
This message is a reply to:
 Message 86 by Dr Adequate, posted 03-03-2008 2:14 AM Dr Adequate has not yet responded

Replies to this message:
 Message 99 by molbiogirl, posted 03-03-2008 7:37 PM Lyston has not yet responded

    
molbiogirl
Member (Idle past 723 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 99 of 180 (459092)
03-03-2008 7:37 PM
Reply to: Message 98 by Lyston
03-03-2008 7:17 PM


I just wanted a plausible theory on genders, not sexual reproduction.

For the umpteenth time, gender is a SOCIAL construct. Not a biological one.

Gender refers to BEHAVIORS. Not naughty bits.

Gender = masculine.
Sex = male.

Gender = feminine.
Sex = female.

Got it?


This message is a reply to:
 Message 98 by Lyston, posted 03-03-2008 7:17 PM Lyston has not yet responded

Replies to this message:
 Message 103 by fallacycop, posted 03-03-2008 8:32 PM molbiogirl has responded

  
Lyston
Member (Idle past 3906 days)
Posts: 64
From: Anon
Joined: 02-27-2008


Message 100 of 180 (459093)
03-03-2008 7:38 PM
Reply to: Message 88 by Percy
03-03-2008 7:18 AM


First, just to clarify a bit more, while you are largely correct when you define theory, where people are taking issue is when you say something like, "it's just a theory," or, "it's a theory, not a fact." The reality is that in science, attainment of status as accepted theory is the highest of achievements for a particular way of interpreting the natural world. Being dismissive of theory is not all that dissimilar to being dismissive of the winning of a Nobel prize.

When you say "largely correct", I hope you mean I finally got something right and that it's not a typo. Yes, I know no one is pleased with my context of "theory", and it may sound like I'm looking at it as "just a theory", but I'm not. I acknowledge as what is the scientifically accepted (and proven through various experiments) method of the origins of the Earth. I'm not dismissing it. If I was, I certainly wouldn't have searched for a site to discuss/debate such a topic.

Stage 2 is actually discussing evolution as defined by evolutionary biologists.

I believe I tried to reach this stage back in comment 58. My quote is...
And, as I said in my second post but probably got drowned out, I'm here to learn, not just argue with or convince anyone.

I had even asked for the theory to outlined. I would, as the OP, like to continue to stage 2 please. :)
This message is a reply to:
 Message 88 by Percy, posted 03-03-2008 7:18 AM Percy has not yet responded

    
Lyston
Member (Idle past 3906 days)
Posts: 64
From: Anon
Joined: 02-27-2008


Message 101 of 180 (459095)
03-03-2008 8:09 PM
Reply to: Message 92 by molbiogirl
03-03-2008 11:36 AM


Funny. Your entire OP deals with the origin of the 2 sexes.

Yes, the sexes, not sexual reproduction nor asexual reproduction. To me, your definition sounds more like "gender stereotyping" (roughly the same as Gender Roles), something that we discussed in my psychology class. They define it as the "cultural or behavioral traits a society associates with ones gender" (and since its in a psychology book, let's just say it involves said "psychological traits"). Dictionary.com (based on Random House Unabridged Dictionary) defines gender as ones sex. En.Wikipedia defines gender as interchangeable with sex. So if my three sources are all incorrect, please tell me.

Gender is generally the purvue of sociology and psychology.

Not the ToE.

Should you wish to continue a discussion of gender, I suggest you start a new thread.


First, may I ask what purvue is? It comes up as incorrect on spell check and is not found in a dictionary. Maybe you meant purview, which would make more sense. Anyway, by definition not found by you, this thread is supposed to be about genders. By definition, it also is about the sexes. I'm not here for a cultural, behavioral, or psychological lesson with things involved with genders... or the sexes if you don't wish to "interchange" them.
This message is a reply to:
 Message 92 by molbiogirl, posted 03-03-2008 11:36 AM molbiogirl has responded

Replies to this message:
 Message 107 by molbiogirl, posted 03-03-2008 10:28 PM Lyston has responded

    
Lyston
Member (Idle past 3906 days)
Posts: 64
From: Anon
Joined: 02-27-2008


Message 102 of 180 (459096)
03-03-2008 8:11 PM
Reply to: Message 93 by molbiogirl
03-03-2008 11:41 AM


No. This is not a ToE thread. This is a mutation and sexual reproduction thread.

It was placed here based on your OP.


Originally title "Problems with Mutation", later changed by someone else to "Problems with Mutation and the Evolution of Sexual Reproduction". That is a wrong title change. It should be titled "Problems with Mutation and the Evolution of Genders". I made the thread, so I should have a rough idea what this is about. -.-
This message is a reply to:
 Message 93 by molbiogirl, posted 03-03-2008 11:41 AM molbiogirl has not yet responded

    
fallacycop
Member (Idle past 3601 days)
Posts: 692
From: Fortaleza-CE Brazil
Joined: 02-18-2006


Message 103 of 180 (459097)
03-03-2008 8:32 PM
Reply to: Message 99 by molbiogirl
03-03-2008 7:37 PM


Dare I say you're splitting hairs?
This message is a reply to:
 Message 99 by molbiogirl, posted 03-03-2008 7:37 PM molbiogirl has responded

Replies to this message:
 Message 106 by molbiogirl, posted 03-03-2008 10:13 PM fallacycop has responded

  
Lyston
Member (Idle past 3906 days)
Posts: 64
From: Anon
Joined: 02-27-2008


Message 104 of 180 (459099)
03-03-2008 8:54 PM
Reply to: Message 97 by molbiogirl
03-03-2008 1:09 PM


Please take the time to educate yourself.
Should you have any questions after you have read the links, we would be more than happy to answer them.

I read them. I'll sum them up real quick: (1) a cell tried to repair damaged DNA by copying another's. (2) Parasite infected a cell and spread its DNA. (3) A cell tried to eat a cell, but instead copied its DNA (or something close to that).

So here's my questions. What happens after the initial mutation? How does it continue?

And, how are you sure that things didn't start out with sexual reproduction and asexual was a mutation? I remember from a 7th grade video of single celled bacterium sending out a tentacle-like thing to another bacteria cell and transferring its DNA to it. How do you know that wasn't the first form of reproduction? I know it's an off chance, but can you prove its not possible? There is no way to tell what the first organism was, in my opinion. Maybe there is, so could someone explain that to me?

You tell me not to call Evolution a theory, but on the contrary, is it not called the Theory of Evolution? You tell me not to call it "just a theory" (which I haven't), but in truth it would have to be "it's just some theories". I understand that this is a field under study currently, but how can "all the evidence that supports the origins of this topic" be divided into not one, but three (four total mentioned) theories. It may be my Pro-Creation views that are biasing my opinions, but it seems hard to just say "yeah, life was created in one of those ways".

I'm not trying to just slap down your views, as you may actually have the "Truth" in one of those theories. Please understand that. I can guarantee that once again this will be seen as "arrogant and cocky", but please understand that it's not. I can here for understanding, not to mock/put down/prove wrong/dismiss Evolution. I want to understand it, as you can tell my knowledge is minuscule and flawed; nothing more, nothing less.

(BTW, when I say theories (plural) I'm referring to the three theories wiki mentioned as origins of "Evolution of Sexual Reproduction")


This message is a reply to:
 Message 97 by molbiogirl, posted 03-03-2008 1:09 PM molbiogirl has responded

Replies to this message:
 Message 105 by molbiogirl, posted 03-03-2008 10:09 PM Lyston has responded
 Message 115 by molbiogirl, posted 03-04-2008 10:32 AM Lyston has not yet responded
 Message 117 by Rahvin, posted 03-04-2008 11:52 AM Lyston has not yet responded

    
molbiogirl
Member (Idle past 723 days)
Posts: 1909
From: MO
Joined: 06-06-2007


Message 105 of 180 (459101)
03-03-2008 10:09 PM
Reply to: Message 104 by Lyston
03-03-2008 8:54 PM


I remember from a 7th grade video of single celled bacterium sending out a tentacle-like thing to another bacteria cell and transferring its DNA to it.

That's sexual reproduction.

Not asexual.

Remember. Sexual reproduction involves 2 organisms and a transfer of genetic info.

Quetzal mentioned bacterial transfer. Did you bother to read his explanation?

And, yes, chances are this was one of the "first" forms of sexual reproduction.

There is no way to tell what the first organism was, in my opinion. Maybe there is, so could someone explain that to me?

While the first organisms were not preserved in the fossil record (at least we haven't found them yet), there is plenty of evidence what they "looked" like.

I work in abiogenesis -- life arising from nonliving bits and pieces. Specifically, I work with ribozymes -- RNAs that auto catalyze.

Because life more than likely arose from an "RNA world", we can be pretty darn sure reproduction was not sexual in the beginning.

You tell me not to call Evolution a theory, but on the contrary, is it not called the Theory of Evolution?

I most certainly did no such thing.

You tell me not to call it "just a theory" ...

I most certainly did no such thing.

... (which I haven't), but in truth it would have to be "it's just some theories".

You have yet to understand the proper scientific definition of a theory.

The theory of gravitation is "just some theories" too.

As is the atomic theory.

As is the theory of relativity.

As is the germ theory of disease.

Betcha don't question the germ theory, huh?

The ToE is the best explanation of the available evidence, just as the theory of relativity is the best explanation of the available evidence.

And the neat thing about both the ToE and the theory of relativity is that both theories make predictions, sometimes decades in advance of the evidence.

Creo claim:

A true science must make predictions. Evolution only describes what happened in the past, so it is not predictive.

Evo answer:

1. Many predictions are possible based on the theory of evolution (e.g., predicting germ/pest resistances to antibiotics/pesticides, predicting general traits/locations of future fossil finds, predicting population responses to selective breeding attempts, etc.)

2. Common descent predicts a positive relation between degrees of homology across species for different proteins. That is, it predicts a close match between phylogenetic trees generated with different sequence analyses.

(http://wiki.cotch.net/index.php/Evolution_doesn't_make_predictions)

Darwin predicted that chimps were our closest cousins. In 2005, we sequenced the chimp genome and sure enough. 1-5% difference.

New Analyses Bolster Central Tenets of Evolution Theory
http://www.washingtonpost.com/wp-dyn/content/article/2005/09/25/AR2005092501177.html

That's the ToE making a prediction 150 years in advance of the genetic evidence.

I understand that this is a field under study currently, but how can "all the evidence that supports the origins of this topic" be divided into not one, but three (four total mentioned) theories.

A consensus hasn't developed in the area of sexual reproduction.

That's common when theories start out. Everybody throws in their 2 cents. Someday, someone is going to deliver the knockout punch.

By way of analogy, back when we didn't have the instrumentation to actually see the structure of DNA (NMR/electron microscopy/etc.), everybody had ideas about what the shape of DNA.

Watson & Crick delivered the knockout punch. The took X rays of a DNA crystal and built a model that explained the X ray images.

Someday we will deliver the knockout punch in the arena of sexual reproduction.


This message is a reply to:
 Message 104 by Lyston, posted 03-03-2008 8:54 PM Lyston has responded

Replies to this message:
 Message 110 by Lyston, posted 03-04-2008 1:28 AM molbiogirl has not yet responded

  
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