Problems with Mutation and the Evolution of the Sexes

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.)

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.

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.

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

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

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.

How did it start becoming a male or female?

This is not an evolution thread?

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

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

We do not discuss gods in the science forums.

Should you wish to discuss faith based nonsense...

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

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

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?

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.

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

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.

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

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.

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

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.

No. This is not a ToE thread. This is a mutation and sexual reproduction thread.It was placed here based on your OP.

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 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.

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.