Glad to help. But first, your last sentence has a false presumption -- male/female genders do *not* have to arise at the same time.
As for the rest of your question, here's a response I wrote a while back in responsen to a similar question:
Though not all creatures reproduce sexually, many do. Why are there two sexes? Did they evolve simultaneously?I see three semi-independent questions here:
1. Why is sexual reproduction advantageous?
2. Why only *two* sexes?
3. How did the two sexes arise from non-sexual ancestors?
To address these, some common misconceptions need to be cleared up.
First, sexual reproduction does not actually require two or more sexes/genders. Sexual reproduction, fundamentally, is just the exchange of genetic material between two (or more) organisms. These organisms don't have to be "male" or "female" in any sense, and in fact many single-celled organisms (e.g. yeast) engage in sexual reproduction by fusing two separate cells, exchanging DNA, then separating.
The second misconception is that specialized male and female forms had to arise at exactly the same time (and *poof*, all at once). They didn't.
So to put it all together, the rise of sexual reproduction as we know it today in animals (and remember that many plants also engage in sexual reproduction, including male/female specialization) could easily have come about through progressive stages such as:
1. Unicellular organisms which reproduced asexually (i.e. by simple division), e.g. bacteria.
2. Unicellular organisms which gained the ability to fuse and exchange DNA in addition to division/budding, e.g. yeast.
3. Simple multicellular organisms (little more than communal colonies of unicellular organisms). Any single still would still have the ability to reproduce (and thus spin off a new colony) by either budding or two-celled sexual exchange. For example simple molds.
4. Simple but more advanced multicellular organisms, where different cells in the "colony" gain the ability to become more specialized based on location or chemical environment. Some regions would become specialized for ingestion of food, for example, while others would become more specialized at sexual reproduction (including specialized gametocyte cells, as well as simple "genitalia" or reproductive sites). Reproduction via single-celled division by any cell would become lost and the organism would now either entirely or primarily on on sexual reproduction (although the gametocytes would still in theory have the option of reproducing asexually). E.g. the higher fungi.
5. Full-blown specialized multicellular organisms as we know them, with specialized organs, etc., with a heavy dependence upon sexual reproduction via specialized organs, and a specialized differentiation between the "donor" and "receiver" cells involved in pairwise sexual reproduction at the cell level (e.g., "sperm and eggs"). At this point the organism is technically hermaphroditic -- there are not "male" or "female" forms. Instead each individual has the anatomy necessary to both donate sperm and produce/nurture eggs, and sexual reproduction involves a bi-directional transfer, with each of the individuals both donating and receiving sperm during the "sex act". E.g., earthworms.
6. From step 5 it's a relatively straightforward step to specialize into two separate sexes, *one at a time*. For example, a mutation could lead to a subpopulation of individuals which have lost the ability to donate sperm, but still have the capacity to produce eggs and have them fertilized. This subpopulation would not die out, since it could still reproduce by being fertilized by the remaining hermaphrodites in the population. Thus it is feasible to have a viable population consisting of a mix of hermaphrodites and "females", without specialized males yet existing. Or it could start in the opposite direction if the first "mutant" subpopulation involved individuals which lost the ability to produce eggs, but still had the capacity to fertilize the remaining hermaphrodites (i.e. "males"). At this point the "specialists" (that is, the "males" or "female" subspecies as the case may be) would be expected to specialize even further in become better DNA "donors" or "receptors", and this would create a genetic "arms race" which would be likely to cause members of the remaining hermaphroditic subpopulation to eventually specialize into the "other" sex, although that could take a lengthy amount of time. But the point is that it needn't arise overnight to "match" the appearance of the "first" sex, as might appear at first glance.
As for *why* sexual reproduction (i.e. why couldn't life have just gotten by for several billion years asexually), there are various forces at work. The first is that the "shuffling" that takes place during DNA exchange produces vast amounts of new variation, far faster than occurs during asexual reproduction. This buffers a species against being wiped out by various challenges, such as environmental changes, a new predator, a new disease, etc. The more that the individuals in a species resemble "clones" of each other, the more they can *all* be felled by a single adverse event which they are all vulnerable to in the same way. With higher variation, statistically many individuals will by chance be less susceptible to whatever adversity strikes the population.
Also, evolution takes place much faster in species which reproduce sexually than in those which reproduce asexually (for a given generation time and birth rate). In a sense a creature that reproduces asexually is its *own* "species", since it doesn't interbreed with any others of its kind. If beneficial mutation "A" takes place in one asexual bacterium, and beneficial mutation "B" takes place in the bacterium right next to it in the petri dish, those two beneficial mutations will never come together, not even in future generations, in order to make a "doubly blessed" individual. But in a species with sexual reproduction, *all* the beneficial mutations that occur in *any* individuals have the potential of being "shuffled together" in a subsequent generation in order to produce individuals which benefit from *all* of those beneficial mutations. Evolutionary "advancement" is greatly facilitated. (And even the creationists who claim not to believe in "macroevolution" should be able to see how this still helps to make beneficial "adaptation" vastly more efficient.)
So through a variety of effects, species which acquired sexual reproduction (with or without separate sexes) would be expected to "outevolve" those species which had not. And as you look around, you'll note that indeed most "complex" organisms reproduce sexually (including plants), and even unicellular organisms frequently do so or find a way to achieve similar outcomes (e.g. "lateral transfer" of DNA in unicellular organisms).
Why two sexes instead of a world of hermaphrodites? Presumably because having specialized males and females opens up more possibilities for more efficient functioning by each. Also, have a two-sex system *enforces* sexual reproduction, whereas hermaphrodites can often "fertilize themselves" -- which combines the worst aspects of both sexual and asexual reproduction with few of the advantages.
As a sidebar it's interesting to note that some animals (which ordinarily reproduce sexually) still retain the ability to reproduce by "simple cell division" at times. Through a process known as "parthenogenesis", females of the species produce a diploid egg cell which is a "clone" of its own DNA, and female offspring are produced without any fertilization by any male (a true "virgin birth"). Animals which can do this include some species of insects (e.g. aphids), fish, amphibians, and reptiles. And apparently a kind of half-assed parthenogenesis has been found to occur in domestic turkeys.
Why *only* two sexes? Probably because while there is a direct route for the production of specialized male/female forms from hermaphroditic beginnings, there doesn't seem to be any obvious way to produce *three* types, nor would there be any obvious advantage to doing so (and several obvious disadvantages).
Once that has been explained satisfactorily, I'll listen to more evidence that the TOE may be true.
Now that it has, what else would you like to see evidence of? Perhaps you could go back to post #14, although I fail to see why you couldn't have "listened" to that even without the sex-ed talk first.
Here's another one from Einstein, which is not particularly supportive of a 4.5 billion-year-old earth:
"People like us, who believe in physics, know that the distinction between past, present, and future is only a stubbornly persistent illusion."
But it would be pretty useless if they did not arise at the same time. They would have died out in one generation so the mutation would have been lost.