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i'm a reasonably thoughtful person. lots of scientific mysteries interest me.

here's something that's really been twisting my noodle lately...

giraffes... well zebra's too.. but im not sure if the stripes are for survival.

now i'm ok with the idea that a giraffe has a long neck to reach food.

ok. good plan.

but how the heck does one grow a longer neck?

is it a matter of all of the shortneck giraffes died so that over the span of thousands of years, the only giraffes around are tall ones?

or howsabout chameleons?

how does one *decide* to change it's skin...

over the span of the next 100 generations i'd like my (what's the opposite of an ancestor?) to be able to fly.

any idea how i could get them started... i'm really not sure how i grow wings.

any pointers would be helpful.

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zebras: stripes act like camoflauge. when there is a bunch of them in a group, they all blend together and look like one huge animal

giraffes: over time the ones who were "freaks" and had longer necks were able to survive because they didnt have to compete with others for food. since these were the ones that passed on their genes, we eventually got the giraffes we know and love today!

im not so sure about the color change thing.
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perhaps the Author of all things Designed them that way?

now I don't know shix from shinola ...
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guess they are still working on the whole transformer thing...
but i mean, we evolved from some kinda monkey/ape deal...
and even before that... symbiotes.
how the heck does an amoebe (or whatever) figure out it's gonna be me in a bajillion years.
(completely ignoring the fact that a sentient being can develop from a sperm and egg... that's just effed up)
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It's not that the short ones necessarily died. They just took a different evolutionary path - they could have ended up as something more like horses. As for the point where there are enough genetic differences to prevent interbreeding... good question.
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It's a good example of why evolution is hard to believe. Mutations, as we know them, handicap and put an animal at a disadvantage. So saying a long-neck was an evolutionary advantage goes against the law of the jungle in eating the weakest/mutated/handicapped.
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not to get all on topic-y but this isnt the case. not all mutations are "handicaps". or at least they arent for every animal. what about the classic moth example we are taught in school? sure those light colored moths didnt survive, but the dark colored (mutant) ones did.
and what about all these new viruses, bacteria, and such? those that are mutants are able to survive treatment with antibiotics and other drugs therefore can reproduce while non mutant ones cant.
mutations are how natural selection happens. if you have some random mutation that lets you survive while your normal neighbor cant, how is that a handicap?
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Agreeing with froggie. Not every mutation is a handicap. In this case, a slightly longer neck makes the animal no more likely to be killed than the others, whereas the short neck ones have a disadvantage because they cannot reach as much food.

And, if the populations of short necked and long mutant necked animals are coexisting because no threat kills them unequally (there is neither significant advantage nor disadvantage to neck length), the long necked animals may prefer to mate with similar long necked ones based on appearance alone. Then you would have two different species. Not to say that is what has happened, but it's a possibility.
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:1: good points CF, esp above...examples, MRSA, VRE and the growing number of antibiotic resistant bacteria you can find in hospitals everywhere
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All that agreement hinges on the environments of mammals being the same as insects or bacteria. There's a huge difference in applying theories on the microscopic and insect level to that of mammals, imho. I won't for a minute argue with you about bacteria, but the life of a giraffe is a whole different existence. For example, look at cheryl's list of bacteria and how fast the mutations that benefit the species happen there. Why doesn't that happen to mammals? Man has been loping alongside giraffes for thousands of years and they haven't changed. Shouldn't the 'improvement curve' of mutations continue? Why the standstill in recent centuries while bacterias only continue to mutate even faster? :shrug:
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well... maybe because bacteria are easier to keep alive? (i don't know much about this so don't mind me while i get unscientific)...
there's a lot that man is worrying about more then survival.. and we are pretty darn complex. i have no idea how i'm able to think thoughts... but i am.
what does a bacteria do all day? (seriously) how long does it live for? if it has a shorter life span, would it improve almost exponentially given the number of generations it could go through faster then a human (who lives like 70 to 80 years?)
if we tackle evolution - will we have to move this to on-topic?
i'm really more interested in how animals change the way they do... if for the simple fact that one or two got lucky, survived when the others didn't, made more babies that had the traits they did, and so on....
..although humans did change skin color depending on where they were... so maybe we can...
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Aren't mutations recessive too? I'm no geneticist, but isn't that the case? So really, if a mutant giraffe neck out there did evolve, current theory is it wouldn't reappear, no? It's astronomical odds making and to say it's happens hundreds of times for thousands of species is a big chunk-o-theory to swallow :shrug:
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Bacteria are much simpler than mammals. I think the evolutionary effect of mutations is greatly reduced when you get to the really complex lifeforms. I'm sure there are a lot of mutations in humans, but they don't show up because it's a relatively small part. Let's say for the sake of example a mutation occurs in one of every 100 bacteria. That's one percent of the organisms will have the mutation. But in people, if one percent of your cells have a mutation that lets you withstand radiation, you won't be able to withstand radiation. But that one bacterium out of 100 will because it's a fully functional organism. For a mutation to have an extensive effect on a complex organism it would have to occur very early in life at the first few cell divisions.
I'm just going off of what seems logical to me - someone let me know if I'm incorrect.
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on the topic of bacteria being able to display mutations more quickly than mammals; single celled animals can develop and reproduce MUCH more quickly than multicelled animals. that may also be a reason that mutations are more readily seen in bacteria.
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this makes me sick!!
:P
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