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Originally Posted by Infinite_Loser
Let's see... Couple of questions here.
1.) Assuming all life on Earth can be traced back to single-celled organisms, how did gender evolve (As asexual reproduction produces offspring which are identical to the parents)? We could assume it's a mutation, but this would only explain how one gender came to be. Both genders would have had to evolve simultaneously, but I don't see how this would be possible without assuming that two separate populations-- One which evolved into male and the other into female-- Came in contact with each other. But this is highly, highly, highly unlikely. Meh...
2.) Furthermore, which came first-- Male or female?
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That's a very good question. Furthermore, I'm going to one-up it. Sexual reproduction is dangerous, and it's a lot of effing work. Think of the countless species that use mating displays; peacocks are a startling example, but even fireflies and crickets serve the purpose. These mating displays are designed specifically (as the name implies) to attract a mate, but they can just as easily attract predators. Furthermore, sex actually makes it
less likely for any one individual to pass on their genes due to sexual competition. Look at us, humans; how much time and energy do we put into sex? Think about it; almost everything we do is designed to project an image of success and prosperity, which in turn is meant to attract a better mate. How much easier would life be without sex?
As it turns out, not very. There are a multitude of hypotheses about why sexual reproduction came about, but they all essentially boil down to one thing; sexual reproduction allows us to improve our genetic structure more quickly and efficiently. When asexual organisms reproduce, the offspring are always exact genetic copies. Asexual reproduction, then, relies on damage to the genetic code in order to evolve. They're basically waiting around for a happy accident. To be fair, sexual organisms do essentially the same thing, but we have a way of stacking the odds in our favour. By creating each offspring from two distinct sets of genetic material we double our chances of mutation occurring (which, in effect, doubles our chances of a beneficial mutation occurring). When taken from the standpoint of a population rather than individuals, this tends to create a more robust organism that's better able to survive the hazards of existence. Furthermore, sex grants us a degree of control over how we evolve as a population through the mechanism of sexual selection. We can choose a mate whose genetic material will give our offspring the best possible chance.
Of course, answering the why doesn't do much to answer the how. The truth is that although we have several hypotheses on the matter, we don't really know how sex came about. We simply don't have enough information about early sexual organisms to really be sure of this. Recent evidence, however, suggests that sex actually evolved first in prokaryotic organisms, which are the earliest cellular organisms to exist. We're not talking about populations of fully formed multi-cellular organisms here; we're talking single cells that are so primitive they predate mitochondria and nuclei. The best hypothesis on the subject that I've come across is that sex originated as a form of predation, with one organism consuming another and then incorporating it's genetic code. In fact, it's likely that it was originally a result of cannibalism, since that creates a stronger possibility of compatible genetic code. This isn't as far-fetched as it sounds when one keeps in mind that prokaryotes don't keep their dna in a nucleus, cordoned off from the rest of the cell; since the dna is just floating in the cytoplasm, it's entirely possible that during a replication cycle a leftover strand from a prey organism could hi-jack the process. Once we've got organisms using two distinct sets of genetic code and benefiting from it, natural selection takes over. It's probable that the first sexual organism started out as one homogeneous population, and once sexual production began it then evolved into two separate strains, one to consume and the other to be consumed. From there we can imagine the two strains becoming gradually more distinct until you end up with two different subsets of the same organism that are dependent on each other for reproduction - in other words, two genders.
So in summary, sex is beneficial because it allows us to evolve more rapidly to keep ahead of predators and parasites, and it's most likely that male and female evolved simultaneously. One doesn't necessarily need to pre-date the other and that occurring is, as you rightly point out, much less likely.
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Originally Posted by roachboy
there need not "be" time for us to experience temporality---if we are basically electrical systems, it's likely that our experience of the fact of time is a projection based upon our experience of the characteristics of the systems that we are--dynamics or rhythms of wave forms, say, or an echo of them on a different scale. that we collectively project time and mark it in particular ways means for sure that our particular modality of experience is temporal, but not that there*is* time. i dont think time is an object that impacts on us. i dont think the big bang "created" it.
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I'd actually like to move on from this threadjack if possible, but in the interest of answering you, I'd like to point out that we are talking about existence here, and not experience. Setting aside the fact that it's impossible for us
not to experience temporality (I'm not sure that's a word by the way, but if it's not it should be), observed evidence does strongly imply both that time is a component of the Universe (which, for the purpose of our discussion here should be defined as the body containing all the stars and galaxies and other phenomena that form part of our existence, observed and unobserved) and that the Big Bang was the origin of our Universe. If we assume these two statements to be true, then it's logical to conclude that if time is part of the Universe and the Big Bang created the Universe, the Big Bang also created time. Taking that as a given, we can further conclude that since 'before,' 'after,' 'cause,' and 'effect' are all words that describe our experience of temporality, said words become meaningless in the absence of time.
Time is not an object. It would be more correct to say that time is a measure; it's a dimension of our Universe, just the same as length, width and height are. And just as we have words and measures to describe length, width and height we also have words and measures to describe time.
Time does not come from us. It's not something that we create. Rather, it's something we exist in. It's part of the chora, if you prefer. Of course, all of this is looking at it strictly from a scientific perspective; if one chooses to approach it from a philosophical perspective, one can be more liberal with definitions and hypotheses.