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Why humans are better than Cyanobacteria?

  1. Jul 22, 2016 #1
    What is an objective criteria of "being successful" for the type of species?

    If we compare humans vs cyanobacteria, then "total mass on Earth" and "the number of species" are both against us, humans ). Of course, you can say that humans are more "complicated", but unless defined it is poetry, not science.

    The only thing I can think of, is when our Sun fades humans (probably) will be able to escape to another stellar systems, while bacteria will die on Earth. However, evolution is not aware of the limited timespan of Sun so it could not be the cause. So while this subject looks intuitively simple (of course, simple evolves into something more complicated), on a second thought I don't see an solid underlying reason for it.
     
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  3. Jul 22, 2016 #2

    Delta²

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    I believe main reason is that we humans are intelligent life. Of course all living beings, and even cyanobacteria have some sort of intelligence, but human intelligence is far more advanced.

    Of course there might be aliens that are much more intelligent than humans.
     
  4. Jul 22, 2016 #3

    Ygggdrasil

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    In our bodies, there are just as many bacterial cells (mostly in our gut) as there are human cells. In some sense, we are just glorified bacterial incubators. As long as humans survive, bacteria will too.

    In purely evolutionary terms, successful species are ones that have not yet gone extinct. As in many fields, present success is not necessarily an indication of future success.
     
  5. Jul 22, 2016 #4

    Fervent Freyja

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    99% of species that the earth has ever hosted are already extinct. For right now, we cannot predict the success of a species- we don't thoroughly understand the variables and conditions responsible for the evolution of even one species. Like my landlord posted above, really only being alive today can meet any such criteria for success. Time-wise, humans are not the most successful species, they haven't been around long enough. There are many extinction scenarios where humans don't have better odds than other species. We are quite vulnerable in comparison.

    Maybe one day humans can take matters into their own hands and increase their chances at future success, but there is still a long way to go before they could colonize another home. Developing more scientifically proven RDA's for nutrition throughout all the stages of child development would be a real nice start before sending people into space to procreate. I have yet to find suitable estimations for my daughter. Considering the efforts and technology involved in the pharmaceutical industry, that is very disappointing.
     
  6. Jul 28, 2016 #5

    jim mcnamara

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    @Fervent Freyja Ask and you might get what you want 'Recommended Daily Intake' (google that from nih or nap.edu):

    There is a full pdf of this stuff, about 650 pages. You have to download or read it "chapter-wise". It goes into excruciating detail - age, sex, upper and lower limits, , footnotes with antinutrients and contraindications, and so on. Plus a large bibliography that you have to read papers from sometimes. Every value seems to have several footnotes, so reading and understanding may be slow.

    Part of Chapter on electrolytes and water.
    http://www.nap.edu/read/10925/chapter/25#606

    Go here, create a free account or login as a guest - this is the National Academies of Science - nap.edu, so it seems okay.
    https://www.nap.edu/login.php?record_id=10925
    You do this chapter by chapter.
     
  7. Jul 28, 2016 #6

    Fervent Freyja

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    Thanks Jim! I did heavy research on infant and toddler RDAs when I began weaning my daughter at 18 months- it was mostly based on outdated work and I couldn't find a detailed list with everything I wanted. I went ahead and custom made one during that time... She is almost 5 now, so I don't have to monitor her as closely and record her intakes anymore- we eat similarly and it's easier to gauge what she receives by watching her intake throughout the day and comparing it with her waste. We aren't totally certain of what trace elements are vital for human development just yet (we might want to know that before colonizing other planets)!
     
  8. Jul 28, 2016 #7

    jim mcnamara

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    @Fervent Freyja then you do know about the USDA nutrient database - the other standard tool in nutrition investigation as well....
     
  9. Jul 28, 2016 #8

    Fervent Freyja

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    Got a link for it?
     
  10. Jul 28, 2016 #9

    jim mcnamara

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  11. Jul 28, 2016 #10

    Fervent Freyja

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    This seems familiar, a quick scan through the file will show you what I meant about so much being outdated. Maybe I should stop being so picky. I did catch some recent entries based off work done in 2014+ though, thanks! :smile:
     
  12. Jul 28, 2016 #11
    Besides, they just start eating stuff off the floor and outside on the ground and in a few more years they'll nag you forever until you take them to McD's. I settled on Wendy's once a month (just thought it was a tiny bit healthier looking) but they still got their way, kind of. Their "C'mon's..." totally outdid my "No's" until they wore me down. I even threw the Geneva Convention rules at them to no avail. But good luck!
     
  13. Jul 29, 2016 #12

    jim mcnamara

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    @Fervent Freyja
    Actually all of the existing research for the RDI was reviewed and some new data brought in just a few years ago. You also have to realize that the final document actually becomes part of US federal regulations. Therefore it impacts school lunch programs, for example. It doesn't change often because of its importance.

    Also, the EU, Australia, and other governments have similar independently developed documents. If you think the US RDI list is messed up or somehow incomplete, check out Australia. You may see a few different values and maybe one added. I have not messed with this in years so I do not know the differences offhand, if any.

    With regard to the USDA nutrient list -
    Since the amount of soluble fiber in asparagus is not going to spontaneously change next week, the expense of reworking most past research outweighs usefulness. You will see new additions like polar bear liver - part of the Inuit people's diet.

    The database too is a really huge deal. The nutrition labels you see on processed foods are virtually all based on the USDA nutrient database, not independent research done by food manufacturers. The food label data is averaged values for a product. And again other countries have analogous data sets.
     
    Last edited: Jul 29, 2016
  14. Jul 29, 2016 #13
    Most of the time they get what they need from the food they eat, even if picky eaters.
    May be a bit too many calories for some.
    Just stay away from too many soft drinks, candies, chocolate bars, and potatoe chips.
    Put fruit out on a table dish for them to pick up as a snack.
     
  15. Jul 29, 2016 #14
    Yep, everything worked out OK.
     
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