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Science

Dinosaurs Grew Fast and Bred Young 63

Smivs writes "It is thought that dinosaurs were able to breed before they were fully grown, much like todays mammals. This ensured that they could breed before they were predated in the violent world of the Mesozoic era. Calcium-rich medullary bone, which, in birds, is used to produce egg shells, was found inside the fossilized shin-bones of two specimens: the meat-eating Allosaurus and the plant-eater Tenontosaurus.Sarah Werning and Andrew Lee of the University of California, Berkeley, deduced from growth rings inside the bone that the two females were aged eight and 10, very young for dinosaurs, which lived to about 30. 'This shows us beyond any doubt how fast dinosaurs grow,' said Kevin Padian, a professor at UC Berkeley's Museum of Palaeontology. 'They're growing as fast as big birds and big mammals.'"
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Dinosaurs Grew Fast and Bred Young

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  • Humans too... (Score:4, Interesting)

    by psychicsword ( 1036852 ) * <The@@@psychicsword...com> on Tuesday January 15, 2008 @06:25PM (#22059294)
    There are example of humans breeding commonly at young ages too.
    In the middle ages it was common for children to get married and although they tended to have kids when they where older, this wasn't always the case.
    A quick google search turned this up:

    In the middle ages with death all around from acts of god(viruses) and where large and very long wars were common it seems that humans did a similar thing.
    Also from what I remember from studying the Middle Ages in school they had around a 40 year life expectancy which is very similar to the Dinos' life expectancy "two females were aged eight and 10, very young for dinosaurs, which lived to about 30." I understand it isn't the best source but like I said it was a quick search you may find another one if you wish.

    If you want an example from more recently here is one.

    According to their own estimate of total population (which is another contentious issue), this implies that around 5.5 million South Africans were living with HIV at the end of 2005, including 240,000 children under 15 years old. [avert.org]
    Now this doesn't mean they are giving birth to kids but they are sexually active and those are just the ones with HIV.
    Now I know this isn't evidence but it is a possibility and I wouldn't be surprised if the dinosaurs did it.
    PS I am just throwing this out I have no experience in the area and it is just a thought. So please nicely correct me if I am wrong.
    • Re: (Score:2, Offtopic)

      by ivan256 ( 17499 )

      Now this doesn't mean they are giving birth to kids but they are sexually active and those are just the ones with HIV.


      Or that they were born to parents that were HIV positive and contracted it at or before childbirth...
      • by sowth ( 748135 )

        Or they had a blood transfusion...

        I don't understand why that poster assumed they all got HIV from sex. Yes, that is one possible way to contract it, but not the only way.

        • I didn't mean to say that the whole group was sexually active I was trying to say that at least some of them would have been sexually active and instead of just saying that there could be people under 15 having sex and kids with no evidence is a little bit weaker than having a number that has strong links to unprotected sex which can lead to giving birth to children. And yes I know that HIV can be transmitted in other ways, such as tainted needles, bad transfusions, and parents who were infected, and any ot
        • Re: (Score:3, Informative)

          by BeanThere ( 28381 )
          The odds of getting HIV from a blood transfusion in South Africa is incredibly miniscule, all our blood is tested. The vast, vast majority of infections is via sexual activity. It's definitely safe to say that the majority of that 240,000 got HIV from some form of sexual activity, so I think the point stands.
          • by cnettel ( 836611 )
            Do you include birth in that number, because if not, I think you need to back it up further.
            • Just to be clear, that wasn't my number. Like I said though, transmission by sexual activity vastly outshadows all other transmission mechanisms, including by birth (odds of a HIV positive mom passing it onto unborn child are not that great, IIRC about 50%).

              The teen pregnancy and abortion statistics in South Africa are off the friggin charts, this is not some secret or unknown or debatable question we're dealing with here, we're talking about pretty well-known facts via other stats. And that's just pregnanc
              • Re: (Score:1, Interesting)

                by Anonymous Coward

                Like I said though, transmission by sexual activity vastly outshadows all other transmission mechanisms, including by birth (odds of a HIV positive mom passing it onto unborn child are not that great, IIRC about 50%).

                5.5 million South Africans were living with HIV at the end of 2005, including 240,000 children under 15 years old.

                So, 5.5 million minus 240,000, divided by two (assuming half are female) gives us 2,630,000 potential mothers. If only one-fifth of them bear children, that gives us 526,000

              • Re: (Score:1, Insightful)

                by Anonymous Coward

                The teen pregnancy and abortion statistics in South Africa are off the friggin charts, this is not some secret or unknown or debatable question we're dealing with here, we're talking about pretty well-known facts via other stats.

                This is the same fear-mongering pseudo-statistic that gets thrown out in debates in the US from time to time. You do realize, don't you, that the phrase "teen pregnancy and abortion" can also include people between the ages 16 to 19? A year-by-year analysis, I suspect, would revea

                • *Sigh* ... you are *completely* clueless, on so many levels, I cannot help you out of it, sorry.
      • There were rumors at one time that a home remedy for AIDS was to have sex with a virgin. A lot of these girls were simply raped if there is any truth to it.
        • Of course there was no truth to it.
          • by Miniluv ( 165290 )
            I believe the parent meant the reports that this rumor was floating around. Seeing as I've heard it reported by both the BBC and NPR and attributed by both to several well respected NGOs doing work on the ground in South Africa and other parts of the continent I'd say it was almost certainly truly being put out there and practiced, though I doubt it amounted for more than a minority percentage of infections.

            The other comment which suggested that prenatal infection was likely a major factor was much more lik
          • No truth to the rumor being present or no truth to the having sex with a virgin would cure AIDS? Or both?

            I figured it would be untrue about curing AIDS, I just don't know much about the rumor itself.
            • No truth to the rumor. By what mechanism could anyone ever be cured of a disease by sleeping with someone who happened not to have had sex before? The rumor led to untold numbers of rapes, unfortunately.
    • Re: (Score:1, Informative)

      by Anonymous Coward
      Well, some of the folk in Africa believe that AIDS can be cured by having sex with a virgin.

      Also, think of the children that got AIDS from their mothers.

      A very sad story.
      • by Amouth ( 879122 )
        all i can say is that whom ever started that hummor over there died or dies of AIDS - very slow very painfuly
    • Kind of like rednecks...
    • Re: (Score:3, Informative)

      by Chris Burke ( 6130 )
      Also from what I remember from studying the Middle Ages in school they had around a 40 year life expectancy which is very similar to the Dinos' life expectancy "two females were aged eight and 10, very young for dinosaurs, which lived to about 30."

      Just a note about these two numbers. "Life expectancy" is an average value that takes into account the length of time that everyone lives, regardless of cause of death, and like all averages without any other context this can skew your perception. It's not that
      • It's that a huge number of people died when they were very young, dragging down the average.
        Is that not what I am saying they had many who died very very young and made the rest reproduce like rabbits to compensate for the death. It could have been similar for the Dinos but instead of miscarriages they kids were eaten.
        • I'm just pointing out that the 40 year life expectancy in the Middle Ages is not a number comparable to the 30 year age of these dinos. That's how long one -could- live, while 40 years was a statistical average across the population.

          The point you were making that they may have had children earlier in the Middle Ages as a consequence of the death rate is valid. Just the point of comparison between the ages of the dinos and humans isn't as evident.
          • The point you were making that they may have had children earlier in the Middle Ages

            I think it's pretty unlikely that they could. Consider that the onset of puberty is getting earlier, that implies that it was later then than it is now. Then add in disease and malnutrituion which are going to retard development rather than accelerate it.

            If people were marrying earlier it was most likely for financial or political advantage, and mainly royalty & the nobility.

          • "That's how long one -could- live, while 40 years was a statistical average across the population."

            An excellent point. 90% of people born during the Middle ages died by the age of 12, but those who reached 13 had good probability of living the Biblical three score and ten years (70).

            "The point you were making that they may have had children earlier in the Middle Ages as a consequence of the death rate is valid."

            But it was the the childhood death rate they were trying to overcome, not that among adults. As i
        • Re: (Score:3, Informative)

          >> Is that not what I am saying they had many who died very very young and made the rest reproduce like rabbits to compensate for the death.

          I have to agree with this statement. Look at family statistics here in the U.S.A. prior to around 1940. Family pictures often show a long line of kids from short to tall. Infant mortality was a very real thing and families were larger back then - pretty much had to be. Heck, after WWII, there was this thing called the Baby Boom to replenish the population.

          By t
      • "Life expectancy" is an average value that takes into account the length of time that everyone lives, regardless of cause of death, and like all averages without any other context this can skew your perception. It's not that people died of "old age" at around 40 (presumably due to the harsh life they lived), they could easily live to be 60, 70, or even older. It's that a huge number of people died when they were very young, dragging down the average. What that 40 year life expectancy is really showing you i

    • Re:Humans too... (Score:4, Insightful)

      by damn_registrars ( 1103043 ) <damn.registrars@gmail.com> on Tuesday January 15, 2008 @07:48PM (#22060280) Homepage Journal

      including 240,000 children under 15 years old.

      HIV can also spread from the mother to the fetus. Those children under 15 could be a population of children who received the virus from their mother, but have not yet died of the virus.

      Although it is possible that some portion of those under-15 children could be sexually active, as well. However, if you scroll further down the same page, you'll see that of the three age groups under 15 (2-4, 5-9, and 10-14), the youngest of the three actually has the highest percent prevalence. This could be indicative of a high rate of transfer of the virus from mother to fetus, with the infected newborn generally living to be around 4 years old.
    • by Gabrill ( 556503 )
      I think you abused the word, "common". Your own blog link not only quotes exceptions as the young royal age of marriage, it further states that non-royalty, or "commoners" typically married around the age of 22, due to family income and responsibilities. Add to that the fact that your comparing reptiles to humans, and we might as well throw in stats for worms, insects, birds, and why not bacteria? Not everything relates to humans, and you shouldn't try to grasp everything as a relation to yourself.
    • Now this doesn't mean they are giving birth to kids but they are sexually active and those are just the ones with HIV.
      Although AIDS and HIV are an STD, if you have AIDS and give birth to a child, there is a chance that the child will be born with AIDS. So just because they have HIV does not mean that they are sexually active.
    • HIV can be transmitted from mother to child, and through poor hygiene (getting other's blood in your own small cuts), and through the (medical or drug) use of needles that aren't properly sterilized. HIV infection is not any clear indicator of sexual activity.

      Not that I would be surprised at sexual activity at 15 - as far as I remember, the average sexual debut age here (Norway) is 15 for girls (17 for boys). It is at least clear that sexual debut before 15 is quite common.

      Eivind.

  • Poor Dinosaurs... (Score:4, Interesting)

    by __aaclcg7560 ( 824291 ) on Tuesday January 15, 2008 @06:30PM (#22059362)
    ...were aged eight and 10, very young for dinosaurs, which lived to about 30.

    And some people still think Logan's Run [imdb.com] is science fiction.
  • by katterjohn ( 726348 ) on Tuesday January 15, 2008 @06:51PM (#22059662)
    and also a dinosaur
    • by Tablizer ( 95088 )
      and also a dinosaur

      Yeah, but just try to reach behind with those little arms to scratch your back.
         
  • by themushroom ( 197365 ) on Tuesday January 15, 2008 @07:14PM (#22059952) Homepage
    > Dinosaurs Grew Fast and Bred Young

    So do urban humans. Did dinosaurs have rap music too?
  • Sarah Werning's profile page @ Berkeley [berkeley.edu] -- Her photos [berkeley.edu]

    I think the story at science daily [sciencedaily.com] is more interesting than the BBC one.

  • This behavior is perhaps what is expected. In a highly predatory environment, it's far more advantageous to reproduce early on because you may not live to reach adulthood. Those kids are less likely to survive than if the organism had waited until maturation, but they are effectively "worth" more as they in turn will reproduce quickly, and so on. This high generation rate as well as very strong forces of selection probably contributed to the increased multitudes of life jumping into existence.
  • Oh, wait, that was Rock&Roll, wasn't it...
    Guess my g-g-g-generation are turning into dinosaurs.
    • Not nececssarily. Elvis lived fast, died young (kind of) but definitely left a big scary corpse...

      ...ducks and runs
  • You were too fast to live, too young to die, bye bye.
  • ...dinosaurs, which lived to about 30.
    Growing up, I was very curious of this figure. Everywhere I saw dinosaurs talked about, it's how long ago they lived, or how long each period lasted. But almost always overlooked is the average lifespan of a dinosaur.

    Glad to finally find out.

    - RG>
    • "But almost always overlooked is the average lifespan of a dinosaur"

      I don't think the figures given are a particularly good guide, because fossilisation events on land in particular tend to be much more frequent when some sort of disaster occurs such as a flood drought, volcano blowing up, etc., and we rarely have very many examples of a particular dinosaur type anyway, so the age that these adult animals died at doesn't necessarily say a huge amount about either their average or maximum life spans under no
  • Dinosaurs Grew Fast and Bred Young

    They also lived fast, died young and left beautiful corpses.
  • This is why the church is against dino porn!

After all is said and done, a hell of a lot more is said than done.

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