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Are there more females than males in the world?

  1. Sep 27, 2010 #1
    If it is true, I will appreciate if somebody can share the proof/source.
     
  2. jcsd
  3. Sep 27, 2010 #2

    Pythagorean

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    I actually saw a proof in an evolution book showing how equal ratios is the stable point. I'll see if I can't find it.
     
  4. Sep 27, 2010 #3

    Monique

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    Last edited by a moderator: Apr 25, 2017
  5. Sep 27, 2010 #4
    Males tend to engage in riskier behavior than females. As a result, their death rates at all ages are higher than for females of the same age.
     
  6. Sep 28, 2010 #5
    Incredible information! Thank you for that. How about in the entire animal kingdom? We can't extrapolate data on humans to the entire animal kingdom. If it's true that females are more than males, why? What's the scientific explanation?
     
    Last edited by a moderator: Apr 25, 2017
  7. Sep 28, 2010 #6

    Monique

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    It depends, some animals can change their sex based on environmental conditions. Nile crocodiles for instance, where the sex is determined by the temperature during embryonic development. Some nematodes live as hermaphrodites, where males are generated spontaneously 0.01% of the time. I'm not aware of data resources on sex ratios in specific species.
     
  8. Sep 28, 2010 #7
    Right, species ratios would likely be an extrapolation of ratios observed in studied populations.
     
  9. Sep 28, 2010 #8
    There's a fish, the name of which I'm currently failing to remember which are all female except for one male in any group. If that male dies, the next largest and healthiest female begins a metamorphosis into a male, and it's not a "little thing" either, but entails major morphological changes.

    I would add that AFAIK, it is all crocodilians who's gender are determined by temp.
     
  10. Oct 19, 2010 #9

    Siv

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    Do you mean throughout the animal kingdom or only humans ?
    I know that in some parts of Asia (including India and China), the sex ratios are horribly skewed due to the practice of female infanticide.
     
  11. Oct 19, 2010 #10

    Monique

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    Hi Siv, that is indeed true (about the skewed ratios). It's in the link I provided: in the United Arab Emirates there are 2.2 males per female, which is on the top of the list.
     
    Last edited: Oct 21, 2010
  12. Oct 19, 2010 #11

    Siv

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    Hey Monique.

    Yes, but thats a different phenomenon. Probably common in the Middle East.

    What I was talking about is plain infanticide. If the baby is a girl, its killed. Sometimes if they do a 6 month scan and discover its female, they abort. Thats why in most maternity wards and scan centres you'll find the notice saying its illegal to ask for the sex of the child during a scan.
     
    Last edited by a moderator: Oct 21, 2010
  13. Oct 20, 2010 #12
    Why is it illegal to ask for the sex of the child? If someone is eager to kill his own child, he'll do it after the birth. It's plain stupid to fight stupid ideas with stupid ideas. Anyway in my country it is not illegal. The birth rate here is 1.06/1 male/female. I think that birth rate can be explained by the different mass of Y an X chromosomes.
     
  14. Oct 20, 2010 #13

    Monique

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    Your argument is ridiculous. Provide some data to show that a ban on in utero gender determination is "stupid".
    Can you provide data on that as well, as far as I know it is just speculation.
     
  15. Oct 20, 2010 #14
    In my country it is legal. Some people want to know. I don't see any benefit of denying them that information. Knowing it can be helpful as you can plan in advance what you will buy for the baby. You can start buying thing appropriate for boy or girl 3 months before the birth instead doing it in hurry. Usually that translates to color choices blue vs. pink, or something like that.

    I said "I think", therefore it is speculation.
     
  16. Oct 20, 2010 #15

    Monique

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    You answer is shocking. I think it should be clear that the combat against illegal abortions is more important than knowing what color to decorate a room in. I don't know what country you live in, but the fact that the birth ratio is close to average tells me that sex-biased abortions are not a major concern in your region.
     
  17. Oct 20, 2010 #16

    Siv

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    Wow, you're nice :tongue2:

    The reason they ban in utero determination of the child's sex is because then the people who dont want girls would abort immediately. And its risky to do so after the first trimester.
     
  18. Oct 20, 2010 #17
    With that attitude you must also forbid teaching medicine. What if someone decides to learn how to make abortions? BTW, who makes the illegal abortions? I guess that are people having the means and the knowledge to tell the gender of the baby. You must fight the people doing the illegal activities, not the people doing their job.
     
  19. Oct 20, 2010 #18

    DaveC426913

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    Betta splendens - Siamese Fighting fish

    A fine example of which is currently eyeing me with consternation, wondering how me being over here pounding on these little square things is facilitating the process of it being fed.
     
  20. Oct 20, 2010 #19

    DaveC426913

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    Sorry Mon, you're out of line. The onus is not on Upisoft to "show any evidence that it's stupid". His argument can be as simple as "I see no justification for it". Rather, the onus is on you to provide data that shows why the ban is justified in the first place (even if it is "well known").
     
  21. Oct 20, 2010 #20

    Monique

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    No, you do not need to forbid teaching medicine. These kinds of abortions are often done without any medical aid, people use needles to extract the fetus or take medications to induce abortion. It is something that is done hidden away from public view and is very dangerous for the pregnant woman. It's something done out of desperateness, because the social status of women is so different from men in those countries.

    DaveC: I don't think that saying that something is "stupid" is a reasonable argument.
     
  22. Oct 20, 2010 #21

    DaveC426913

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    Which is why I rephrased the words for him without changing the meaning. He can just as easily have said "I see no justification for this." This is perfectly valid, and puts the onus on you to offer an explicit reason why this practice is in place, which can then be debated.
     
  23. Oct 20, 2010 #22

    Monique

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    There is a difference Dave, there is a standard to uphold on the forum and people should learn to be articulate.
     
  24. Oct 20, 2010 #23

    DaveC426913

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    I agree. It's just that your initial answer of "provide some data to back up your claim of stupidness" served only to dignify a poor argument with a worse one.
     
  25. Oct 20, 2010 #24

    Monique

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    Let's get back on topic, shall we? Statements should be argumented.
     
  26. Oct 20, 2010 #25
    I'm sorry I didn't know the proper synonym for "stupid" that I had to use here. After all English is not my first, even not second language.

    Back to the topic. You can't stop motivated killer by hiding the gun. The same is valid here. You can't stop a motivated baby killer by denying access to information. You have to fight the motivation of the crime.
     
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