by Blueblades 18 Replies latest jw friends
To me, while evolution appears to be more or less the way it happened, there are still some concepts of the actual macrochanges that i can not see my way through. It's not that they didn't happen, but what caused them, and over how long a period of time. Also, as for the cause, was it from a force internal of nature, or from an external force. If external, was it a force coming from nature, or from elsewhere.
S
terry,
i know what you're saying. and i guess the same could be said about the big bang, or the general theory of relativity. there is always the slight chance that it could be turned on it's head. absolute certainty, right?
satanus,
hey man. while i don't see the real difference between a bunch of micro changes and one larger macro change, i do know what you are talking about. with regards some of the data, it seems that Stephen J. Gould's Punctuated Equilibrium explanation, makes some real sense. but yet, when approached from another angle, it seems to sound a bit silly. so it's tough. in the end, i prefer cumulative gradualism over all, when speaking on geologic time scales. but sometimes, around great extinctions for example, while still making sense, it also starts to seem dangerous, in my mind.
i know that punctuated equilibrium has fallen out of vogue lately, but in hindsight, it seems to fit some of the data best.
if there were some sort of super "race" of aliens out there, that aided life on earth in some way, then i would find that most wild. and who knows? there is absolutely no data to support the hypothesis, but from an imaginative standpoint, it would be thrilling!
cheers,
TS
I suppose aliens is a possibility. I was thinking forces from a more subtle dimension, forces w perhaps a small amount of intelligence, possibly up to our level, also possibly much lower like on the level of an ant. Imagine a god, a spiritual being node w the intelligence of an ant. Or, maybe a whole bunch of them. There must be an sf story about something like this.
Spass the dube, man
I suppose aliens is a possibility. I was thinking forces from a more subtle dimension, forces w perhaps a small amount of intelligence, possibly up to our level, also possibly much lower like on the level of an ant. Imagine a god, a spiritualbeingnode w the intelligence of an ant. Or, maybe a whole bunch of them. There must be an sf story about something like this.
nice! hive-mind-god.
(takes big ol' toke)
TS
Tetra
We see microevolution, but not macroevolution, although it must have happened. The interesting thing about microevolution is that it has not changed animals passed the boundary that would fall within what the wt calls 'kinds'. Not that that proves anything. I mean even goatherders could put that together from observations.
It's the hows, whys and how longs of macroevolution that i wonder about.
S
Is it just me or is TS looking more and more like Captain Cavemaaaaaaaan!! Ok, too many beers tonight.
It's the hows, whys and how longs of macroevolution that i wonder about
I think you'd be intrigued with the work being done one homeobox genes, Satanus. They can greatly affect overall structure of an organism with relatively small changes in code.
Sounds like jeans sponsered by some rapper. Thanks, i'll google them
S
roy,
thanks! LOL. but seriously, i would rather be called what i am (a paleolithic caveman in front of a computer) than some other lie, like special creation. he he.
satanus,
We see microevolution, but not macroevolution, although it must have happened. The interesting thing about microevolution is that it has not changed animals passed the boundary that would fall within what the wt calls 'kinds'. Not that that proves anything. I mean even goatherders could put that together from observations.
It's the hows, whys and how longs of macroevolution that i wonder about.
"macroevolution" is really just a human abstraction to help us explain evolution. all change is micro. there is no such thing as "macro-change", in a true technical sense. a good example of this concept are Ring Gulls. i have explained it before, but here is a sufficient explanation from http://scitec.uwichill.edu.bb/bcs/courses/Biology/BL14A/bl14al02.htm
Ring Species
There are several ring species, the most famous example is the herring gull (Larus argentatus). In the British Isles, these are white. They breed with the herring gulls of eastern America, which are also white. American herring gulls breed with those of Alaska, and Alaskan ones breed with those of Siberia. But as you go to Alaska and Siberia, you find that herring gulls are getting smaller, and picking up some black markings. And when the series of populations is followed all the way back to Britain, they have become Lesser Black-Backed Gulls (Larus fuscus).
So, the situation is that there is a big circle/ring around the north pole. As you travel this circle, you find a series of gull populations, each of which interbreeds with the populations to each side. There is a complete series of intermediate subspecies of one species or the other. In the British Isles, the two ends of the circle are functionally two different biological species of bird. They do not interbreed. They nest in different sites and have different appearances.
so all macro-change really boils down to cumulative micro-change.
and what is change? change is mutation during embryonic development based on environmental pressures. this is genotypic change. genetic change. change that stays with you, in your genome, and that you pass on to offspring. true speciation (so-called macro-change) occurs when a member of a species can no longer breed with the other members of "their" species, and create a new species or sub-species. but this is not a big mutation jump. it's not obvious at first. most often, it is but one micro-change that was enough micro accumulation to speciate . and if that organism survives to breeding age (assuming she finds someone to breed with), then they have now passed their mutations on. usually, they survive because their (and their ancestor's cumulative mutations) help them survive in some new environment.
so, on a genetic level, it's hard to say what "macro" actually is, as it is all so fine-grained over time. we are all "transitional forms" compared to our parents (or the previous organism in genetic space), and our children (or the next organism in genetic space). we are all transitional compared to where our offspring will be 20 years, 200 years, 2 million years from now. and genetically, we are always mutating very slightly from our parents. our chromosomal addresses are the same, but the digital content of the genome at those locations can be, and are often, different from our parents. a more extreme mutation would be the addressing system actually changing on the chromosome. and this happens too sometimes. every once in a darwinian blue moon.
if you want to call a mutation macro, because it caused a subspecies (that for all intents and purposes looks morphologically like it's parents), then that is fine, but it's an abstraction of hindsight for descriptive purposes. or if you want to call a change in the chromosomal addressing system, macro, then that is fine, as it is extreme. but not compared to the changes that lead up to it. in comparision to those, it's micro.
or conversely, take chimps, who look very different from us (relative to hindsight), but share something like 99% of our genome. we have 23 pairs of chromosome, and the chimp has 24 pairs. we both share a common ancestor. at some point in our history two chromosomes joined to make one, or the chimps split to make two. but at the point where we branched (not to mislead that it was a homo sapien that branched) "us" and the "chimps" looked quite similar, relative to that point in history. it's just that now we look different, after many many more micro-changes that we call macro in hindsight. the chromosomal addressing system between chimps and us don't match up anymore, but there are large swaths of content (or code, if you will), that do match up. this is the result of many small changes, not one big obvious change.
TS
