Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site sphinx.UChicago.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxn!ihnp4!gargoyle!sphinx!beth From: beth@sphinx.UChicago.UUCP (Beth Christy) Newsgroups: net.origins Subject: Re: Lemme axe yew a question (Evolutioners) Message-ID: <1021@sphinx.UChicago.UUCP> Date: Tue, 20-Aug-85 18:07:04 EDT Article-I.D.: sphinx.1021 Posted: Tue Aug 20 18:07:04 1985 Date-Received: Sat, 24-Aug-85 01:49:34 EDT References: <2517@vax4.fluke.UUCP> Organization: U. Chicago - Computation Center Lines: 79 In Message-ID <2517@vax4.fluke.UUCP> hopeful@fluke.UUCP (Rod Blaine Foist) writes: >Sposin evolution's true. Ah hear tell that we hewmens an da >GOrillas (da apes) come fum da same ancestry. Now let's call dis dude, the >po' boy fum which Chita an us come, let's call him A-0. Lets call us, A-N. >Nowif'n Ah got da picture right, they's a bunch a characters in between ol >A-0 an us A-N types. How many of these in-betweeners (call 'em "n") is >they, Ah don't know. Ah also hear tell that they's two camps--the >gradualists (Ah'll call um Grads) an da Punctuated Equilibrium types (Ah'll >call um Puncs). > >Well, whether da Grads or da Puncs is right only means how many "n's" they >is, right? Now Ah also heared that, as Stanley Friesen once said (April >9th), "Evolution *only* talks about increased *adaptation* and *not* >improvement". Soif'n that means that each "n" between A-0 an A-N was more >adapted, now hyere's mah question: How come there ain't any of these dudes >ALIVE today? We got apes an we got hewmens still alive an well today. How >come they (apparently) ain't nothin in between LIVING? Well, your question is postulated in a rather misleading way, but I'll give it a try anyway. What's misleading is the concept of A-0...A-N. Numbering things with integers sort of implies a clear cut break between A-i and A-i+1. We need to be aware that there are infinitely many numbers between i and i+1, and a lot of transitional phases between what are now clearly distinct forms (obviously not *infinitely* many, but a lot). Now to (try to) answer the question: In some sense, there *are* transitional forms of humans alive today, or at least transitional traits. Let me clarify: suppose for example that humans originated in Africa in climates similar to those that exist there now. Further suppose that dark skin and hair were common traits among some group A-0 of humanoids of the time. If those traits recessed in the humanoids who moved to different climates, they'd be transitional traits for those folks, yet would still be present in those humanoids who remained in similar climates. Now there is great diversity among humans who live in the same climate in terms of skin color, hair color and texture, eye shape, ..., since people have moved around alot recently (the folks who live in the suburbs will probably just have to try to picture this in their minds :-) - sigh :-( ). So the transitional traits that one group may have passed through are still present in other comingling groups. Now why isn't there *greater* diversification, i.e. why doesn't an A-N and an A-(N-x) (read that "A sub N minus x") exist now, where A-N and A-(N-x) are seperate *species*? Well, for some portion of A-(N-x) to develop into a whole new species A-N, enormous amounts of time must have passed during which some of A-(N-x) were exposed to new environments. Now if, during that amount of time, all environments available to A-(N-x) changed, it's quite likely that the remainder of the group would have adapted to the changes, thereby becoming A-N or B-M or X-Y. So some particular climate would have had to remain essentially constant over vast periods of time. Well, there just aren't that many places that have stayed that constant that long. The possible exception would be deep ocean, and in fact extremely old species have been found there. We certainly haven't explored deep ocean thoroughly, and we may well find intermediate species and their shallower-water descendants still living (for that matter we may have already - I'm not really that up on it). There are very old species in other places, but the fact that they've existed in the varying environments that have existed over time would indicate that they're pretty stable, and hence no sub-group would have been likely to evolve into a new species. Which is only *my* long-winded explanation. Now that you've made it this far into it, I suppose it's too late to mention that it may well be totally off the mark. Oh well - you pays your money, you takes your chances. -- --JB (Beth Christy, U. of Chicago, ..!ihnp4!gargoyle!sphinx!beth) "Oh yeah, P.S., I...I feel...feel like...I am in a burning building And I gotta go." (Laurie Anderson)