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Foreword: I’m going to mention sexual organs here, so you have an aversion to reading this stuff, here’s my warning to you (I talk about it medically, there’s no sexualisation or anything).

Some of you have heard the religious hokum about how Eve was created from one of Adam’s ribs – and some have had the misfortune of meeting idiots who actually believe that men have one less rib than women because of this. Prepared to get scienced.

Now, of course, this isn’t an attack on religion, it’s just another informative article. I only bring up the religious flipside to address a conceptually wrong idea – that somehow women came from men and men were “here first”. This couldn’t be farther off the mark because, as the title reveals, all men were once women.

Let me explain. For those of you who don’t know how human gender is determined, it’s based on what’s known as the XY sex-determination system. This system applies not only to humans, but most mammals, some insects and some plants. To put it simply, women have two of the same sex chromosomes (XX) whereas men have two distinct sex chromosomes (XY).

Here’s the crux of the matter – as an embryo, everyone is “female” until the Y chromosome kicks in about 6-8 weeks after conception. Technically speaking, the embryo is undifferentiated (though it takes chromosomes from the mother and father to make the pair), but I’m addressing the conceptual flaw of “men came first” here, not the medical technicalities. The thing is, the Y is the only thing that determines whether the embryo becomes a male, therefore the “default” will be the only other option: female. Abnormal embryos with XXXY will still be male because of the Y, so we can see that the X is not a determining factor, and is thus the “default” case. My medicine student friend pointed out to me that the embryo isn’t considered female (because it already has XX or XY), which is why I put “female” in quotation marks. Remember, this is a conceptual issue – if one were to say “men came before women” they would be more correct to say “women came before men”, though medically they would both be technically wrong (the embryo is often referred to as a proto-female; I’m just saying that it’s more female than male, not that it’s definitely female). That’s also why males have nipples, which pretty much serve no purpose. Also, some of you may know that the female clitoris and male penis grow from the same genital tubercle when in embryo form (by the way, both enlarge when aroused). The tubercle is undifferentiated – the only thing determining whether it turns into a penis or clitoris is exposure to testosterone. Medically, the clitoris is said to be the homologue of the penis (the female counterpart of the penis). Some have oversimplified this by saying “the clit is just an under-developed penis”. Well, now that we know all men were once women, it’s more accurate to say the penis is just an oversized clit.

So the truth is, all men were once women, and thus all men come from women (not the other way around!).

Now before the guys go off with their tails between their legs, and the girls float off with their big heads, I wanted to point out that this fact has another implication. Women often call men “primitive”, but in reality, women are actually the baser form. In fact, studies have shown that the male Y chromosome is evolving much faster than the rest of the human genetic code.

“The Y chromosome appears to be the most rapidly evolving of the human chromosomes,” said study co-author Dr. David Page, director of the prestigious Whitehead Institute in Cambridge and a professor of biology at MIT. “It’s an almost ongoing churning of gene reconstruction. It’s like a house that’s constantly being rebuilt.”

But make sure to take this information in context! This doesn’t necessarily mean that men are the more evolved sex, since the Y chromosome only determines a person’s sex. However, the Y chromosome is undoubtedly special. Unlike the other 44 chromosomes, it is an individual and not part of a pair, and it is also an “evolutionary powerhouse”. Scientists are expectant of future discoveries regarding the Y chromosome as it shows so much potential (in multiple areas, not just determining sex).

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I try to keep this blog religion free but this post will probably cut close to the line (and if it crosses a line, it’s your fault not mine – religion doesn’t have to conflict with evolution, you just want it to). I just want to make it clear I’m not attacking any beliefs – I just want to make some things clear whilst championing truth and logical reasoning. If it makes you sleep better, you’re free to believe that evolution was “set into motion” by a god, but the fact is that evolution is very real.

On a side note, I’m sick of theists trying to use science to disprove science. It doesn’t work that way. You can’t suddenly decide to believe in a certain, small amount of science taken out of context to “prove” your god, and then turn around and ignore all the other science pointing to another answer. If you’re a believer, stick to your beliefs and stop trying to justify it. If you feel the need to use an opposing ideal to verify your own, then you obviously don’t have enough strength in your beliefs to rely on it alone. You don’t see scientists saying god proves that there is no god.

Back on topic: here are some facts about evolution that many people might not know.

  1. The Catholic Church has changed its public stance to accept evolution as a fact, the same way it changed its opinion on a heliocentric solar system (Earth revolving around the sun). I lead with this because the Vatican seems to have no problem reconciling its beliefs with this particular scientific fact, although its reasoning is a bit sketchy. In a nutshell, the Church says they’re not sure whether cosmological and biological evolution exist but if it does, then it’s because of god. As for evolution, the Church accepts that we evolved from other biological life forms, but claims that god “specially created” our “soul”.
  2. Humans did not come from monkeys. This claim is an oversimplification commonly employed by theists to try and disrepute evolution and is a combination of both the Strawman and appeal to emotion logical fallacies (making it a doubly stupid claim). First of all, humans are closer to modern apes than monkeys, which automatically makes theists using this claim a whole deal more ignorant. Second, we didn’t evolve from these apes either, we share a common ancestor. About 5-8 million years ago, our common ancestor diverged into two separate lineages, one of which went on to become modern apes and the other became us humans. In fact, even this is oversimplifying it. Our common ancestor evolved into the earliest hominid species 5-8 million years ago, and since then, there have been dozens of different species of human-like creatures. It’s not as simple as take a monkey, pop, oh look it’s a human; it’s millions of years of dozens of species evolving slowly over time, with homo sapiens being the greatest survivor. It’s almost like the mitochondrial Eve.
  3. Humans have roughly a 96% DNA similarity to chimpanzees. This figure was previously as high as 99% but has been revised over time. DNA comparison by itself is somewhat limited so let’s introduce the next point.
  4. The missing chromosome between humans and apes has been discovered. Some of you might know about this, but for those who don’t, chimpanzees, gorillas and orangutans have 48 chromosomes (if traced back far enough, humans have a common ancestry with these three separate species, with chimps being the closest). Humans, however, have only 46 chromosomes. If common ancestry were to be valid, one would expect humans to have a same number of chromosomes as our distant cousins. Chromosomes can’t just disappear, which would be fatal, so there are only two possibilities – either humans do not share a common ancestry with apes or two chromosomes got fused. Well, Dr. Ken Miller and other associates have located the two chromosomes that were fused through whole genome sequencing techniques. Chromosomes have centromeres which are DNA sequences used to separate them in the middle during mitosis and telomeres, which are DNA sequences at the ends. If two chromosomes were fused, we would have telomeres in the centre of the chromosome (instead of at the end). Guess what? They found the chromosome, it’s the Human Chromosome #2, which shows the exact point at which this fusion took place.
  5. There are many examples of evolution happening right before our eyes. It’ll take far too long for me to list  them and why, so I’ll give a quick list of the names and you can Google these for yourself if you don’t believe me (which you should). Peppered moths, three-toed skinks, crabs and mussels, Italian wall lizards, cane toads, Darwin’s finches, butterflies and parasites, viruses and superviruses (SARS, swineflu), flatfish, Australian skinks, elephants, fish in the Hudson River and many other species of lizards besides the ones I’ve mentioned.

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