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Interesting Stuff Thread

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  • Registered Users Posts: 1,454 ✭✭✭bogwalrus


    things are getting much clearer for me now. tnx again for your time.


  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    bogwalrus wrote: »
    things are getting much clearer for me now. tnx again for your time.

    No problem. If you have any other questions feel free to ask :)


  • Registered Users Posts: 23,283 ✭✭✭✭Scofflaw


    Yep, with the notable exceptions of dogs and cats...

    Which form interesting exceptions, since they're not domesticated in quite the same way as the others - although, if one thinks about it, the dog, like the pig, is actually omnivorous, but otherwise fits the bill (as does the pig). Cats, of course, don't, but I suspect not everyone would agree that cats are domesticated, as opposed to merely being domestic.

    cordially,
    Scofflaw


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Apparently the dog (or perhaps wolf) was the first animal to be domesticated. The idea goes that initially early humans would follow wolves which would lead them (inadvertently) to prey. The humans with their weapons were capable of taking much larger prey than the wolves could. Once the humans took their fill the wolves could scavenge what remained. Apparently then over time the symbiosis grew, becoming more organized.

    Not so sure about cats. Perhaps we noticed having them around kept away rats etc.


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Could this be an example of evolution in action?

    http://dsc.discovery.com/news/2008/07/25/whale-shark-size.html

    Natural selection favoring the small it would seem.


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  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    Galvasean wrote: »
    Could this be an example of evolution in action?

    http://dsc.discovery.com/news/2008/07/25/whale-shark-size.html

    Natural selection favoring the small it would seem.

    Various shark species have been shrinking over the 400-million odd years that they've been around. Perhaps the more recent selective pressure is something to do with a shortage of food... The article cites human targeting of the larger individuals though.


  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    anyone got a decent article on how evolution creates new/different species?

    Right, try this:

    http://thebiologista.blogspot.com/2008/07/great-wormtown-spade-disaster-part-1.html

    It's a couple of pages but it's a nice no-jargon kinda storybook version of speciation. It brings in the effects of mutation, habitat fragmentation and the main mechanisms of evolution itself and it shows how they combine to end up generating two species from one. It's done in a very basic, almost piss-take style but as a jumping-off point for discussion of speciation it's pretty good.

    Hope that's a help.


  • Registered Users Posts: 23,283 ✭✭✭✭Scofflaw


    Galvasean wrote: »
    Could this be an example of evolution in action?

    http://dsc.discovery.com/news/2008/07/25/whale-shark-size.html

    Natural selection favoring the small it would seem.

    It's interesting to consider that, over time, anthropogenic habitat fragmentation might well lead to a form of 'virtual' island dwarfism. I'm not sure if that has had time to develop anywhere as yet, though - possibly somewhere like England or other long-established anthropogenic environments.

    cordially,
    Scofflaw


  • Registered Users Posts: 6,401 ✭✭✭jtsuited


    bloody great idea for a thread. surprised it was never here before.

    interesting thing in the bees article about how competing for social rank causes the brain to develop.
    Would that mean that stratified society is actually making us more intelligent as we are forced to compete?


  • Registered Users Posts: 6,737 ✭✭✭Asiaprod


    Scofflaw wrote: »
    It's interesting to consider that, over time, anthropogenic habitat fragmentation might well lead to a form of 'virtual' island dwarfism. I'm not sure if that has had time to develop anywhere as yet, though - possibly somewhere like England or other long-established anthropogenic environments.

    cordially,
    Scofflaw
    See the lost tribe of Pilau (National Geographic)
    [Edit] Oops, my bad, was not anthropogenic, but it is interesting


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  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    jtsuited wrote: »
    bloody great idea for a thread. surprised it was never here before.

    interesting thing in the bees article about how competing for social rank causes the brain to develop.
    Would that mean that stratified society is actually making us more intelligent as we are forced to compete?

    That would depend on the nature of the competition. In modern human society, competition is almost entirely based on intelligence, but it's hard to say if we can yet observe evolutionary changes based on this due to the relatively short time scale.


  • Closed Accounts Posts: 27,857 ✭✭✭✭Dave!


    Hey Atomic Horror, I sent you a PM!


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Various shark species have been shrinking over the 400-million odd years that they've been around. Perhaps the more recent selective pressure is something to do with a shortage of food... The article cites human targeting of the larger individuals though.

    But would it not be unreasonable to speculate that the hunting of larger specimens (to get the bigger fins), in a sense favouring them over the smaller ones, could be taking them out of the gene pool leaving the smaller ones to populate the species?
    Of course this is all a bit hypothetical since whale shark breeding patterns are poorly understood at best. Their young and mating habits are virtually unknown. We don't yet know what age/size they reach sexual maturity at.


  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    Galvasean wrote: »
    But would it not be unreasonable to speculate that the hunting of larger specimens (to get the bigger fins), in a sense favouring them over the smaller ones, could be taking them out of the gene pool leaving the smaller ones to populate the species?

    It's rather hard to say whether the reduction in the average size is actually representative of a change in the frequency of any specific genes without more extensive work. If larger sharks are being targeted and killed then we would fully expect the average shark size to reduce for that reason alone.


  • Registered Users Posts: 23,283 ✭✭✭✭Scofflaw


    That would depend on the nature of the competition. In modern human society, competition is almost entirely based on intelligence, but it's hard to say if we can yet observe evolutionary changes based on this due to the relatively short time scale.

    The general consensus appears to be that we still are evolving, quite rapidly, but that it's a political minefield to say so, since it immediately throws up the whole issue of race.

    Much of the evolutionary pressure indeed seems to be concentrated on brain functions, but there are other issues - an increase in frequency of genes that offer greater resistance to HIV in Africa, for example.

    There's quite a good article on human evolution here on New Scientist.

    cordially,
    Scofflaw


  • Registered Users Posts: 6,401 ✭✭✭jtsuited


    Scofflaw wrote: »
    but that it's a political minefield to say so, since it immediately throws up the whole issue of race.
    yup that would get very very messy but i think would be an incredibly cool area to investigate.

    like i figured that where resources were more scarce and conditions less hospitable (the further north in europe) the more intelligent peoples prospered.
    Hence scandinavians being so good at poker, and having one of the most educated populations in the world (i think i read the average age of leaving education was late-20's).
    Just a hunch (and not one I'd hold with much conviction) but I figure there is something to it.


  • Closed Accounts Posts: 6,609 ✭✭✭Flamed Diving


    jtsuited wrote: »
    and having one of the most educated populations in the world (i think i read the average age of leaving education was late-20's.

    Would that not be symptomatic of their political system? What if their education system was entirely private with fees akin to the USA?


  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    Scofflaw wrote: »
    The general consensus appears to be that we still are evolving, quite rapidly, but that it's a political minefield to say so, since it immediately throws up the whole issue of race.

    Much of the evolutionary pressure indeed seems to be concentrated on brain functions, but there are other issues - an increase in frequency of genes that offer greater resistance to HIV in Africa, for example.

    As with the sharks above, it's easy to see the effects of selection over quite short time periods. The increasing prevalence of alleles that protect against HIV follows this too- at least one that I know of has been extant for several centuries and is now undergoing positive selection (they mention it in the article: CCR5(delta)32. I have no doubt at all that our species is very much still evolving. But over the time that we've been able to directly observe it, this sort of allele frequency change is about as much as we've seen in humans. If it weren't, the Lenski E.coli results would not have been such a big deal! There's no compelling reason for us to assume that human evolution has halted at all and I'm always confused as to why people would imagine that it has. Until the day we eliminate sexual reproduction in favour of 100% fidelity cloning, we will evolve.


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    I think human evolution could well be skewed by our own success. With our modern medicine and technology people who would have died off before breeding are now living longer and managing to reproduce. Ditto for fertility treatment.
    With this whole new fangled fad of monogamy that we have now we're getting many one male/one female reproductive situations, where in nature one female may reproduce with several males, generally only the fittest of the season. We're also very complicated. Unlike in other species where one or only a couple of traits would make a male desirable to a female, in humans we have loads. Some are desirable for their looks (which can be skewed should someone get say plastic surgery, making them good looking but without help from their genes), some for their minds, some for physical abilities, etc.
    It comes across to me as if there is no evolutionary pressure in humans to head in a particular direction.


  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    Galvasean wrote: »
    I think human evolution could well be skewed by our own success. With our modern medicine and technology people who would have died off before breeding are now living longer and managing to reproduce. Ditto for fertility treatment.

    This merely means that a wider range of traits are being inherited. Selective pressures will still act upon these and despite modern medicine, many conditions will still result in a reduced (albeit improved relative to prehistoric man) likelihood of reproduction.
    Galvasean wrote: »
    With this whole new fangled fad of monogamy that we have now we're getting many one male/one female reproductive situations, where in nature one female may reproduce with several males, generally only the fittest of the season.

    Fitness is nothing more than fitness to reproduce. It can be measured by many traits.
    Galvasean wrote: »
    We're also very complicated. Unlike in other species where one or only a couple of traits would make a male desirable to a female, in humans we have loads. Some are desirable for their looks (which can be skewed should someone get say plastic surgery, making them good looking but without help from their genes), some for their minds, some for physical abilities, etc.

    Just means that sexual selection is more complex than it might have been before. The selection pressure still exists, people still die childless even in the western world.
    Galvasean wrote: »
    It comes across to me as if there is no evolutionary pressure in humans to head in a particular direction.

    I very much disagree. The fact that there are many selective pressures merely makes our likely evolutionary course unpredictable.


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  • Registered Users Posts: 23,283 ✭✭✭✭Scofflaw


    Galvasean wrote: »
    With this whole new fangled fad of monogamy that we have now we're getting many one male/one female reproductive situations, where in nature one female may reproduce with several males, generally only the fittest of the season.

    Hmm. Actually, our genitalia and sexual dimorphism suggest that we are 'naturally' semi-monogamous. We produce relatively little sperm, the vast majority of which under ordinary circumstances is simple fertile sperm rather than 'competitive' sperm designed to block or disable other males' sperm. We also lack the variety of twiddly bits (flanges, barbs, etc) found on the penises of competitive species (competitively polyandrous ones). We don't have the level of sexual dimorphism found in species which are permanently polygynous or polyandrous, although we do have some.

    Altogether, these traits, as well as the extended period of postnatal care required for human infants, suggest that we are naturally mostly 'serially monogamous' rather than polygamous, but that we use a flexible mixture of sexual strategies depending on resources.Human history tends to bear this out.

    cordially,
    Scofflaw


  • Registered Users Posts: 9,788 ✭✭✭MrPudding


    I think this is a repeat, but I know I missed it, so here is a heads up.

    Dawkins on Darwin:

    http://www.channel4.com/video/the-genius-of-charles-darwin/series-1/

    MrP


  • Registered Users Posts: 6,401 ✭✭✭jtsuited


    Scofflaw wrote: »
    Hmm. Actually, our genitalia and sexual dimorphism suggest that we are 'naturally' semi-monogamous. We produce relatively little sperm, the vast majority of which under ordinary circumstances is simple fertile sperm rather than 'competitive' sperm designed to block or disable other males' sperm. We also lack the variety of twiddly bits (flanges, barbs, etc) found on the penises of competitive species (competitively polyandrous ones). We don't have the level of sexual dimorphism found in species which are permanently polygynous or polyandrous, although we do have some.

    Altogether, these traits, as well as the extended period of postnatal care required for human infants, suggest that we are naturally mostly 'serially monogamous' rather than polygamous, but that we use a flexible mixture of sexual strategies depending on resources.Human history tends to bear this out.

    cordially,
    Scofflaw
    jeepers good points.
    good one to remember the next time some drunken conversation about monogamy comes up in a nightclub!!!


  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    jtsuited wrote: »
    jeepers good points.
    good one to remember the next time some drunken conversation about monogamy comes up in a nightclub!!!

    Yep, the "science" of that seems to be a favoured topic of the ladies man. Usually by comparison to species who have nothing resembling our biology or social structure. People really will use whatever vague interpretations of philosophy and science they can recall to justify just doing whatever the hell they like.


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Yep, the "science" of that seems to be a favoured topic of the ladies man. Usually by comparison to species who have nothing resembling our biology or social structure. People really will use whatever vague interpretations of philosophy and science they can recall to justify just doing whatever the hell they like.

    You know worker ants follow their leader's instructions without question...
    Bow before me insects!!!


  • Registered Users Posts: 5,888 ✭✭✭AtomicHorror


    Galvasean wrote: »
    You know worker ants follow their leader's instructions without question...
    Bow before me insects!!!

    :eek:


  • Registered Users Posts: 30,746 ✭✭✭✭Galvasean


    Your awe pleases me.


  • Closed Accounts Posts: 27,857 ✭✭✭✭Dave!


    Does anyone know of any research, etc., on how evolution relates to make-up? I'm talking about lipstick and eyeliner and all that sh*t...

    I seem to remember it being mentioned in some talk I was watching on t'interweb.

    Physical attraction is usually a proxy for finding an appropriate mate, and there are common things that each sex finds attractive in the other because it makes them look healthier or stronger, eg. women like broad-shoulders on men, both sexes like symmetry, and so on...

    Make-up is used to emphasize or alter particular facial features by playing with our perceptions, making lips look fuller, introducing shadowing to areas to make the nose look more slender, eyes look bigger, or whatever! And by so doing, you are making yourself fit more into the pattern which the opposite sex is likely to find attractive, and so you are more likely to mate and propagate your genes :)

    I'm just looking for more info on this, as I think it's pretty interesting.

    Failing that, if someone could direct me to research about attractiveness itself, and what is considered attractive by each sex. As I mentioned earlier, broad shoulders, symmetry, etc.


  • Closed Accounts Posts: 6,609 ✭✭✭Flamed Diving


    Dave! wrote: »
    Does anyone know of any research, etc., on how evolution relates to make-up? I'm talking about lipstick and eyeliner and all that sh*t...

    I seem to remember it being mentioned in some talk I was watching on t'interweb.

    Physical attraction is usually a proxy for finding an appropriate mate, and there are common things that each sex finds attractive in the other because it makes them look healthier or stronger, eg. women like broad-shoulders on men, both sexes like symmetry, and so on...

    Make-up is used to emphasize or alter particular facial features by playing with our perceptions, making lips look fuller, introducing shadowing to areas to make the nose look more slender, eyes look bigger, or whatever! And by so doing, you are making yourself fit more into the pattern which the opposite sex is likely to find attractive, and so you are more likely to mate and propagate your genes :)

    I'm just looking for more info on this, as I think it's pretty interesting.

    I believe there was a study done with birds where they would take two male birds and attempt to make one look for attractive by giving it an artifically bigger tail, or a little decorative 'hat' on its head. Then they released one female into the cage to see which one she would choose. It turns out that the female chose the male which was 'dressed up' the majority of the time. I don't have a link or anything, it was on TV when I saw it.


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  • Closed Accounts Posts: 27,857 ✭✭✭✭Dave!


    I believe there was a study done with birds where they would take two male birds and attempt to make one look for attractive by giving it an artifically bigger tail, or a little decorative 'hat' on its head. Then they released one female into the cage to see which one she would choose. It turns out that the female chose the male which was 'dressed up' the majority of the time. I don't have a link or anything, it was on TV when I saw it.
    Cheers, that's pretty interesting. I'd be curious to see how chimps and the likes act in aa similar situation. Probably the same.


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