why learn Evolution?
Jan. 26th, 2005 10:12 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
acroyearA poster on talk.origins asked the honest question, in light of how the curricula for most American biology classes treat evolution as some "separate section" irrelevant to the main text, why bother.
"In what way? What, besides evolution, requires evolution to understand?"
answer the following questions, where "why?" doesn't mean "what was the intent" as philosophy understands it -- it means what it means in science: "what sequence of events led to this state that we see today?"
having taken only one high school biology class (rushed through summer school at that) and not a single collegiate class, I can answer or at least theorize an answer for every single one of those questions: because I understand evolution (and a little bit about continental drift). these are BASIC, simple questions that any child might ask. with the knowledge of evolution, even a child can understand the answer. with it, the jigsaw of the biological world is complete.
with it, the answer to the current events question, "why did the stem cells the scientists were permitted to use become corrupted" exists. without it, there would be no way of understanding the genetic puzzle involved.
without it, the patterns are there, but no way to connect them or extrapolate from them. the similarities are there between species, but not the relationships. the ecological niches are there, but with no way of understanding how they got to be that way when the land or water was very different tens, hundreds, thousands, or milllions of years ago. without it, "because God made it that way" is an answer. but repeat that answer to children long enough and you'll end up with an extremely disillusioned child. "Because i said so" is NEVER an answer to the inquiriing mind, and so should never be an answer to a question of science.
with evolution, as with any truly scientific theory, one can predict. one can predict the impact of a geological catastrophe. one can predict the impact of a man-made catastrophe. one can realize what *might* happen, not just in terms of those creatures that die out (that's the *easy* part), but what will become of those that live through it.
even if we're wrong (of course we will be; nature is FAR more interesting than anything *humans* can dream up), we can predict, we can test, we can wait.
without it, there would be no way life itself would ever survive a catastrophe the magnitude of a nuclear war or asteroid collision, or even another ice age or global warming. if the species that exist today are all that is, this planet will die. and yet at any point in this planet's history, one could have said that.
yet life survived. the few survivers lived and bred; many of their children died, but a few didn't -- maybe those few had something special about them, something slightly different -- something as simple as slightly thicker skin, or thicker fur, or less fur, or ever so slightly better vision, or slightly more webbed feet, or the ability to glide for longer distances by giving just a little "push" up with a wing.
or maybe one particular tribe could survive a massive drought by being able to take hollow gourds, fill them with water from the one remaining source, and leave them behind buried in the sand along the hunting path so that they could drink the water later, surviving the long walk from the hunting grounds back to the original water source with the food the rest of the tribe needed to eat...
little, tiny, changes, and isolation from interbreeding with others that might restore the dominant genes to the next generation. that's all it takes. one thing lives, another dies. a tiny difference. almost unnoticeable.
but add up tiny changes over even the few generations between 15000 years ago and now, and the differences are astounding -- "artificial" selection has created ALL of the varieties, the "breeds", of dogs today from a single wolf-like ancestor. only 15000 years and a weinerdog is almost utterly incompatible in our minds with a st. bernard.
no obvious "mutation", no change in the children seemingly any better or worse than any other, yet the varieties evolved. they're here today.
do that over 600,000,000 years and tell me what a dog might look like.
we don't know. but we can guess!
without evolution, we couldn't even do that. without evolution, biology ceases to be a science; it would be only a classification system, requiring no creative thought, only rules and policies. "''cause God made it that way."
an easier life, sure, but true science was never easy. simple, elegant, almost artistic. but not easy.
"In what way? What, besides evolution, requires evolution to understand?"
answer the following questions, where "why?" doesn't mean "what was the intent" as philosophy understands it -- it means what it means in science: "what sequence of events led to this state that we see today?"
- 2 species of the same type of animal on separate islands in the galapogos are still slightly different, seemingly for no reason other than cosmetics. why?
- some moth species have the exact same color patterns on them as butterflies in the same region, yet their wings are chemically completely different, even to the point of reflecting completely different patterns in the ultraviolet spectrum. why?
- australia is full of marsupials, a type of mammal that otherwise only exists in *one* species outside of that region, here in north america. why? the fossil record shows an animal much like that one, only the size of a VW Bug, having lived 3 milllion years ago in south america. how did that happen? is there any connection at all?
- chickens carry the genetic instructions for growing teeth, and they also contain instructions that actually supress the hormone that triggers that growth -- reintroduce that hormone, and a reptile tooth grows. why?
- outside of the influence of man or disease, most ecological niches reach a state of equilibrium, where predator-prey ratios reach a point of stability. though the predators and prey may be different, the ratios are generally consistent throughout the world (and throughout the fossil record). why?
- mountain goats are able to climb what appears to be a 90 degree rock-face, and yet mountain lions are still able to hunt them. why?
- hunting animals tend to have forward-facing eyes, big ears, and an incredible sense of smell; nocturnal creatures tend to be colorblind; rabbits and many rodents, in spite of being extremely social animals, don't make much noise with their vocal chords; why?
- wales and dolphins are obviously mammals, with hair (whiskers), mammary glands, live birth, caring for young; what is their connection with the rest of the earth-born mammals with legs, feet, forward-facing nostrils?
- pandas have this stub of a digit, a *6th* finger, growing on the side of their paws, which they use for stripping leaves off bamboo. studies over the last 200 years of western presense in china has shown that this "thumb" is bigger in the current generation of pandas by almost an inch over 200 years ago when biologists first did their studies. why?
having taken only one high school biology class (rushed through summer school at that) and not a single collegiate class, I can answer or at least theorize an answer for every single one of those questions: because I understand evolution (and a little bit about continental drift). these are BASIC, simple questions that any child might ask. with the knowledge of evolution, even a child can understand the answer. with it, the jigsaw of the biological world is complete.
with it, the answer to the current events question, "why did the stem cells the scientists were permitted to use become corrupted" exists. without it, there would be no way of understanding the genetic puzzle involved.
without it, the patterns are there, but no way to connect them or extrapolate from them. the similarities are there between species, but not the relationships. the ecological niches are there, but with no way of understanding how they got to be that way when the land or water was very different tens, hundreds, thousands, or milllions of years ago. without it, "because God made it that way" is an answer. but repeat that answer to children long enough and you'll end up with an extremely disillusioned child. "Because i said so" is NEVER an answer to the inquiriing mind, and so should never be an answer to a question of science.
with evolution, as with any truly scientific theory, one can predict. one can predict the impact of a geological catastrophe. one can predict the impact of a man-made catastrophe. one can realize what *might* happen, not just in terms of those creatures that die out (that's the *easy* part), but what will become of those that live through it.
even if we're wrong (of course we will be; nature is FAR more interesting than anything *humans* can dream up), we can predict, we can test, we can wait.
without it, there would be no way life itself would ever survive a catastrophe the magnitude of a nuclear war or asteroid collision, or even another ice age or global warming. if the species that exist today are all that is, this planet will die. and yet at any point in this planet's history, one could have said that.
yet life survived. the few survivers lived and bred; many of their children died, but a few didn't -- maybe those few had something special about them, something slightly different -- something as simple as slightly thicker skin, or thicker fur, or less fur, or ever so slightly better vision, or slightly more webbed feet, or the ability to glide for longer distances by giving just a little "push" up with a wing.
or maybe one particular tribe could survive a massive drought by being able to take hollow gourds, fill them with water from the one remaining source, and leave them behind buried in the sand along the hunting path so that they could drink the water later, surviving the long walk from the hunting grounds back to the original water source with the food the rest of the tribe needed to eat...
little, tiny, changes, and isolation from interbreeding with others that might restore the dominant genes to the next generation. that's all it takes. one thing lives, another dies. a tiny difference. almost unnoticeable.
but add up tiny changes over even the few generations between 15000 years ago and now, and the differences are astounding -- "artificial" selection has created ALL of the varieties, the "breeds", of dogs today from a single wolf-like ancestor. only 15000 years and a weinerdog is almost utterly incompatible in our minds with a st. bernard.
no obvious "mutation", no change in the children seemingly any better or worse than any other, yet the varieties evolved. they're here today.
do that over 600,000,000 years and tell me what a dog might look like.
we don't know. but we can guess!
without evolution, we couldn't even do that. without evolution, biology ceases to be a science; it would be only a classification system, requiring no creative thought, only rules and policies. "''cause God made it that way."
an easier life, sure, but true science was never easy. simple, elegant, almost artistic. but not easy.
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no subject
Date: 2005-01-27 03:41 pm (UTC)when i use either word, i use it by its scientific meaning.
ID'ers are attempting to come up with evidence that *proves* God exists, in that it proves that there is no other way for something to have happened except that God did it. this is attempting to use proof in the scientific sense. it is also impossible. if such evidence conflicted with a specific part of evolutionary theory, evolutionary theory would adapt. just like (and i've used this before) Einstein didn't show Newton was wrong, just that he was using abstraction model that doesn't scale when the speed of light is concerned. Newton is utterly wrong, yet he isn't in that his core remains intact for the vast majority of the observations we see.
so it is with Darwin.
the point is that there are conceptual arguments by which any *scientific* theory can be DISproved, as you said. evolution is one such case. any form of spontanious speciation, where a creature is born with genetic traits that are not traceable to the genetic parents in any way would disprove *current* evolutionary theory in a second.
an easy test. we'll wait.
on the other hand, ID and creationism is not scientific becuase it can NOT be disproved. if at any point you're allowed to say "God waves his magic wand" and presto something different was born.
yes, you could *say* that, but it wouldn't be science.
and for that matter, if we saw that "miracle" happen, what should science do? capitulate? suddenly declare in Nature and Scientific American "There Is A God!"?
no -- it would see that as an act of nature and study it to find out what was different. it didn't follow the rules we know, so what rules did it follow?
would modern evolutionary theory change? of course it would. such a "miracle" would explain a great many things. the theory of how new species came along would change -- their survival as a species by natural selection WOULD NOT. that is the critical thing -- regardless of the specifics of how speciation happened, other parts of the theory (that we're related to apes, that complex life can still only come from other life, that animals adapt to survive in an environment or die before having children) all still hold up. just like gravity continued to suck in spite of the fact that Newton was wrong in his details. and just as Newton is still important to know in spite of how wrong he was at certain details, so too is Darwin.
would such a miracle have a detectable cause?
THAT's the key question -- if its cause is detectable, its science, and seeming "miracle" or not, eventually we could determine the rules by which such an event happened.
if its cause is undetectable, THEN science can claim there's a God.
but it would have to be REALLY darn undetectable...