Nipples

Peg writes:

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they dont have anything to do with sex do they?

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Biologically? Not really. The reason men have nipples is because women have nipples.The human is hermaphroditic during gestation up until about day 53 when various hormones start kicking in. The common thing you may have heard is that "everybody starts female," but that isn't true. Everybody starts hermaphroditic.Now, it is true that in the absence of the the male hormones that XY fetuses normally secrete, the fetus will develop along female lines, that doesn't mean the fetus is female. A human fetus has all structures for both male and female sexual characteristics. The vas deferens is not simply a different version of a Fallopian tube. Instead, the fetus has structures for both the vas deferens (Wolfram ducts) and Fallopian tubes (Mullerian ducts). As the fetus develops along male or female lines, the other structures regress. A male fetus will secrete Mullerian regression hormone which causes the Mullerian ducts to regress.This carries over to other structures in the body. Males have mammary glands just like females do. It's just that in males, the body never gets enough estrogen to make them develop. This is why male athletes who are on steroids often get what is colloquially called "bitch tits": Testosterone is processed by the body into estradiol, which is a female hormone. This can cause gynecomastia, or development of the mammary tissue.Why don't male nipples regress the way their proto-uterus and -Fallopian tubes do? Because there is no disadvantage in having nipples on a male.You will note that there are some people who have extra nipples. They follow what is called the "milk line." You will notice that other mammals have more than two nipples, unlike humans. Mark Wahlberg (yes...that Mark Wahlberg) has an extra nipple.Biologically, this isn't that bizarre. There is a body plan to how the fetus develops from a single cell into a multi-cellular organism. We should not be surprised if every now and again, some cells get "duplicated," as it were.

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Perdition writes:

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Evolution didn't push us towards monogamy

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Why not? Lots of species pairbond. Evolution affects behaviour. Why wouldn't evolution affect the behaviour of humans?

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Peg writes:

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all animals have their own list of predictable behaviors, but humans do not

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You really think this? And I mean that on both sides of the question.So I guess psychology is completely bogus. I mean, how on earth could we possibly think we could study human behaviour and understand it? Humans are "unpredictable"! And I suppose all those warnings about never approaching a strange animal lest it do something unpredictable were just bunk.

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we have the ability to choose how we want to behave...that is a huge difference

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It's a difference in degree, not kind. Other animals have the ability to choose how they want to behave, too, and humans can be easily manipulated. There's a reason advertising works.

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Peg writes:

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it makes sense because animals live by instinct but humans live by law

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So how to explain chimpanzees who live by law? And how to explain human instincts?There's a reason advertising works.

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whats the difference between the two?

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Nothing, really. You seem to think that humans aren't animals.

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If evolution was the answer, then humans would be subject to instinct like every other animal on the planet

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And they are, just like every other animal on the planet.Or do you deny the Stanford experiment? You remember the one. That's where they split students up into groups of "prisoners" and "guards" and made to simulate a prison. It quickly devolved into a real life version of Lord of the Flies with the guards becoming more and more abusive, drunk on their power they had.So is anybody surprised that it happened again at Abu Ghraib?

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We choose to live by laws

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...except for when we don't. Surely you have noticed the police who patrol our cities looking for people breaking the law.

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therein lies evidence of design rather then randomness.

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Except chimps have law, too.Again, you seem to be under the impression that humans aren't animals.

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

grandfather raven writes:

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we see rule-based social behavior outside of primates, too. heck, wolves have "laws" that they must follow, or be rejected by the pack

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And let's not forget that chimps and dogs both have a sense of "fairness," though it gets expressed differently.That is, dogs understand the concept that rewards should be given for good behaviour. If one is getting rewarded for behaviour and the other is not, the non-rewarded dog will stop complying since he can see that it isn't fair.Chimps, on the other hand, also understand the value of the reward and expect that to be equal. Dogs don't recognize that one is getting a prime reward while the other is getting a lesser reward. They both got rewarded and thus it's "fair." Chimps, on the other hand, can tell the difference between a good reward and a pathetic one and the ones getting the pathetic reward will stop complying since they can see that it isn't fair.Human "law" is a difference in degree, not kind.

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Hyroglyphx writes:

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The reason men have nipples is because mammals in utero, during the first gestational phase, are all female.

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Incorrect. During the first 53 days of gestation, all fetuses are hermaphroditic. At that point, XX fetuses will start regressing their male parts while XY fetuses will start regressing their female parts.How do you think hermaphrodites come into being? Parasitic twins?I highly recommend Hormones: Messengers of Life for a more detailed description of how biological sex develops in humans and how it can go awry.

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In fact, a penis is nothing more than an enlarged clitoris since as the fetus was developing she started out as a female but later developed as a male.

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You realize that it's the other way around, yes? A clitoris is an undeveloped penis just as the male mammary system are undeveloped breasts.Again, all humans start as hermaphrodites.

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

caffeine writes:

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I've been unable to find out if this is true, but I remember reading somewhere that all human embryos begin to develop vans deferens. If it is, then I don't think it makes sense to describe early embryos as females - they're undifferentiated.

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Close, but not quite.All human embryos are hermaphrodites up until about the 53rd day of gestation. A human embryo has complete structures for both a uterus and Fallopian tubes as well as for the vas deferens and epididymis along with a single set of undifferentiated gonads.The vas deferens is not just rejiggered Fallopian tubes. Instead, the embryo has both Mullerian ducts which will become Fallopian tubes if the fetus develops along female lines and Wolffian ducts which will become the vas deferens if the fetus develops along male lines.This is what allows hermaphrodites to exist in the first place: You need to have both sets of structures in order to have both develop.Again, I highly recommend Hormones: Messengers of Life for more details.

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Rrhain

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Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.