There's also the results of a study which sems to indicate that most (but not all, about 80%) Native Americans are descended from the same family, identifiable by a genetic mutation that differs from all other humans, and ocurred 20,000 - 50,000 years ago.

------------------
"We shall not yield to you, nor to any man." -- Freak, The Mighty.

 

------------------
You know, when Comedy Central asked us to do a Thanksgiving episode, the first thought that went through my mind was, "Boy, I'd like to have sex with Jennifer Aniston."

-Trey Parker, co-creator of South Park

 

------------------
"Sully, for Shame! And don't be foolish! What are we trying to practice every day? If our friendship depends on things like space and time, then when we finally overcome space and time, we've destroyed our own brotherhood! But overcome space, and all we have left is Here. Overcome time, and all we have left is Now. And in the middle of Here and Now, don't you think that we might see eachother once or twice?"
- Jonathan Livingston Seagull
 

------------------
"I told you. You're dead. This is the afterlife. And I'm God."
--Q to Picard, "Tapestry".

I'll have to wait until you post that info you're talking about, because I apparently don't get Geographic anymore. And I mean the information, as in who found these fossils, how many people, how many fossils, where, when, good descriptions, etc. No opinions.

"There's also the results of a study which sems to indicate that most (but not all, about 80%) Native Americans are descended from the same family, identifiable by a genetic mutation that differs from all other humans, and ocurred 20,000 - 50,000 years ago."

Cool...

That reminds me of something I read a long time ago about mitochondria. Something about showing that mitochondria indicate that there must have been a single female progenator for the entire human race. Anyone know anything about this?

Can we pick up this debate where we left off, or does this have to be on the one topic of dino-bird missing links? If we can pick up where we left off, anyone know where we were? All I remember is that I had just made a point about, if a mutation occured that created a specimine that could not reproduce with other members of the previous species, then the exact same mutation would have to occur in a member of the opposite sex, or the reproductive mutation would die out immediately. I don't think I ever got an answer.

I don't suppose we could get the original thread unlocked and stick all this stuff on the end of it? Might be fun to make it even longer. : )

------------------
For every complex problem, there is a solution that is simple, neat, and wrong.
- H. L. Mencken
 

Just doing my bit as a librarian to encourage their use.

It is a mistaken belief that a SINGLE mutation causes a change in species. It does not. Rather, a group of changes, passed on and accumulated within a single community of organisms, over a long period of time (which can vary depending upon the reproductive cycle of the species in question, and many other things) does. It ain't like the X-Men, toots.

------------------
"We shall not yield to you, nor to any man." -- Freak, The Mighty.

 

I'd visit my local library, but it won't be finished for another six months, at minimum. The closest branch library to my house is 25 minutes away in bad traffic and construction, and I don't think I can convince someone to give me a ride just to go look at a magazine. This new branch that's being built, however, is three blocks from my house, which makes me extremely happy. We do use our library, though. I must have checked out 20 books in the last month (mostly Asimov, with a little Clarke some Bear). Librarian? Cool...

------------------
For every complex problem, there is a solution that is simple, neat, and wrong.
- H. L. Mencken
 

Well actually Catholics do accept homosexuals, what they forbid is premartial sex either for both heterosexual or homosexual persons. However are you telling me Tora that Lutherians have nearly accepted the fact of premartial sex amoung homosexuals, because that wouldn't make sense since heterosexuals can't dot that (and it not be a sin I mean).

------------------
HMS White Star (your local friendly agent of Chaos and a d*mn lucky b*st*rd:-) )

You probably haven't read my posts on this issue before, because I know exactly what the Catholics accept. Note that I said homosexual sex and not just homosexuals themselves.

"However are you telling me Tora that Lutherians have nearly accepted the fact of premartial sex amoung homosexuals, because that wouldn't make sense since heterosexuals can't dot that (and it not be a sin I mean)."

I'll have to ask her again. I specifically asked if they're allowed to marry, but she said that while they can't marry, their sex is allowed.

If anyone has to reply again, do it in a new thread. I didn't want to go off the topic TOO much.

------------------
"I told you. You're dead. This is the afterlife. And I'm God."
--Q to Picard, "Tapestry".

"I hearby find Lisa Simpson innocent of all charges. I'm also issuing a restraining order on religion. It must remain 200 feet from science at all times."

Brilliant episode.

------------------
"And much of Madness, and more of Sin, and Horror the soul of the plot."
--
The Conqueror Worm, by Edgar Allan Poe
 

[kidding! I lurk among the local shelves once a week, and every time I'm humbled by how *much* there is to know.]
 

And are you sure the catholic Church accepts Homosexuals? Because I always thought that was one thing that the bible is crystal clear on, that homosexuals are evil people who have cold black hearts which pump not blood like yours or mine, but rather a thick, vomitous oil that oozes through their rotten veins and clots in their pea-sized brains which becomes the cause of their Nazi-esque patterns of violent behavior, or isn't that true?

I've got a friend that knows that book that the quote about homsexuality being evil and all that is in, but he's not answering the phone right now. Ah well.

------------------
You know, when Comedy Central asked us to do a Thanksgiving episode, the first thought that went through my mind was, "Boy, I'd like to have sex with Jennifer Aniston."

-Trey Parker, co-creator of South Park

 

Changes in species are not made within individuals, but within communities, usually ones isolated from the parent group.

One mutation appears, is spread through the community, (but not to the parent group), and becomes common. Then another. Then another. And another, etc.

Eventually, through successive mutations WITHIN the community, it becomes a separate species. Able to interbreed with each other, but no longer with the parent group, because too much genetic change has occured. There is NO point at which one individual becomes unable to breed with other members of the community, because the whole community's genetic code is changing along WITH the individuals'.

------------------
"We shall not yield to you, nor to any man." -- Freak, The Mighty.

 

------------------
HMS White Star (your local friendly agent of Chaos and a d*mn lucky b*st*rd:-) )

The only way a specimine would be considered a new species would be if a mutation occured WITHIN its reproductive system, making it genetically incompatible with anyone without the mutation. (Well, there could also be some radical mutation in which the number of chromosomes changed, but if the number of chromosomes was lessened, vital DNA code would certainly be lost, and if the number of chromosomes was increased, the DNA would have to be gibberish, and would interfere with the normal DNA. In either case, natural selection would ensure that the mutation was not passed on.) Such a mutation would insure, by it's very nature, that it was not passed down to other generations. No other kind of mutation would create a new species.

------------------
For every complex problem, there is a solution that is simple, neat, and wrong.
- H. L. Mencken
 

Listen, it's really very simple. Take a bunch of sheets of paper. Divide them into two separate groups.

Now, fold one sheet once. That's a small, say 1-bit of DNA mutation.
Fold the rest of the sheets in that group. That represents the mutation being spread to the other members of that community (assuming it's selected for. Some are, some aren't. That's why it takes a LONG time.)
Now, fold one of the sheets a second time, in a different direction. That's a second mutation.
Fold the rest of the sheets in that group, again, too. That's the spreading.
Do this a dozen or so times. What you end up with is a bunch of objects, all similar, all having the same original form as, but now also very different from, the objects in the first group (the unfolded bits of paper.)

That's how it works. Massively simplified, of course.

------------------
"We shall not yield to you, nor to any man." -- Freak, The Mighty.

 

And for another thing, if everything was a mutation of a basic pattern, how do you explain the fact that not everything has the same amount of DNA? Any chromosomes added would be gibberish, basically millions of mutations, and thus many fatal ones would be included. And any chromosomes removed would be deadly, because I seriously doubt that we could afford to loose 2% of our DNA. If it's all mutation, then we'd all (all being all life, not all people) have the same number of chromosomes. Our DNA would just be different variations on a single ancestor, with variables changed, but none added or subtracted.

------------------
For every complex problem, there is a solution that is simple, neat, and wrong.
- H. L. Mencken
 

*smug grin*

Well, not really. I prefer 'Christian' now.

But one thing our R.E. teacher admitted was that the bible was absolutly crystal clear on homosexuality. Not some metephour, or anything like that. Not 'consider the lillies of the field', the bible states that homosexuality is a very evil deed.

He didn't agree, and neither did we, but as proper catholics we must treat homosexuals as evil snake worshippers.

And not have before marriage sex. Or use contraception.

*ahem*

And that happens...

------------------
You know, when Comedy Central asked us to do a Thanksgiving episode, the first thought that went through my mind was, "Boy, I'd like to have sex with Jennifer Aniston."

-Trey Parker, co-creator of South Park

 

...

That is...what I meant to say was...Cyclops? What are you talking about? Some childish endeavor that I would never engage in, surely.

*ahem*

As I meant to say, um...oh yeah. Don't you mean *smug mode*, Liam? (And yes, I did try snpp.com. They don't have the guides for that season done yet.)

Omega said: Well, he said some stuff. To be honest, I'm really not sure what you're driving at. What "sharp" division are you speaking of, exactly? You seem to be assuming that evolution works on the level of individuals. It does not. Instead, as First said, it operates on communities. And, over time, all the members of an isolated community are going to share a unique genetic code that will prevent them from interbreeding with members of their old species.

For instance, let's say that...oh, Jennifer Connelly and I live in some freaky beatnik commune. And so, as men and women often do, we have a child. Said child contains a minor genetic mutation. Said child goes off and does same with other members of same commune. Process repeats until minor genetic mutation is shared in the entire commune. New gene proves useful, so it continues to change. Eventually, everyone here becomes a new species. (A spectacularly attractive one, I might add.) How? Because the members of the commune are more closely related genetically than those outside of it. Meaning that I can reproduce with them, even though are genetic codes are not identical. But I can no longer reproduce with outsiders, who have not been able to incorporate ANY versions of this new mutated gene.

Or, in other words, say the gene is A5. I can reproduce with people who have A4 and maybe A3. But not people with A1, and those are the people outside of the commune.

------------------
"And much of Madness, and more of Sin, and Horror the soul of the plot."
--
The Conqueror Worm, by Edgar Allan Poe
 

The division of either being able or not able to reproduce with other specimines. See my next example.

I think I see what you're driving at, but it still doesn't work. You're suggesting multiple grades, as opposed to my two; saying that person A could reproduce with person B, and B could reproduce with C, but C could not reproduce with A (please ignore gender). Even if it was possible, it still wouldn't make any difference. B and C would have a child, and their child would inherit B's ability to reproduce with A, thus not creating a different species.

------------------
For every complex problem, there is a solution that is simple, neat, and wrong.
- H. L. Mencken
 

Besides, why are we arguing this? The whole process has been observed in the natural world.

------------------
"And much of Madness, and more of Sin, and Horror the soul of the plot."
--
The Conqueror Worm, by Edgar Allan Poe
 

------------------
HMS White Star (your local friendly agent of Chaos and a d*mn lucky b*st*rd:-) )

------------------
"And much of Madness, and more of Sin, and Horror the soul of the plot."
--
The Conqueror Worm, by Edgar Allan Poe
 

there are many ways in which mutations might occur, and virtually none of them involve changes to entire chromosomes. (this is why you have FAR more species than there are #'s of chromosomes possible in a cell.)

Yes, the paper is still paper, much as the DNA in our bodies is still DNA. HOWEVER, the SHAPE of it has changed radically, far moreso than the small percentage which our DNA differs from, say, pan troglodytes (a chimp).

"The average human being has about 50-100 mutations (differing them from EITHER of their parents,) of which about 3 may actually matter (they actually change a protein.) If the typical mutation were deleterious, life would go extinct in short order." - parenthetical expressions mine.

------------------
"We shall not yield to you, nor to any man." -- Freak, The Mighty.

 

------------------
You know, when Comedy Central asked us to do a Thanksgiving episode, the first thought that went through my mind was, "Boy, I'd like to have sex with Jennifer Aniston."

-Trey Parker, co-creator of South Park

 

------------------
It's all about the Pentiums, Baby!
"I'm down with Bill Gates, I call him Money for short
I phone him up at home and I make him do my tech support"

Furcula (wishbone) formed of two clavicles fused together in the midline.

Now we start getting on shaky ground. It used to be thought that the possession of a furcula distinguished birds from dinosaurs. Indeed, up until recently even clavicles were few and far between in even theropod dinosaurs (the suggested closest group to the birds and from which the birds evolved - see Ostrom 1976). However, it has been found that theropod dinosaurs did indeed have clavicles (e.g. Bryant &Russell 1993) and they have been found in several species, e.g., Segisaurus, Velociraptor, Euparkeria, Ornithosuchus, Saltoposuchus, Ticinosuchus. Also, Chure & Madson (1996) reported furculae in a non-maniraptoran, allosaurid dinosaur.

It has been found that the clavicles are often small and poorly ossified. This is no surprise, since they are of little evolutionary advantage to your average theropod dinosaur. However, birds too show this variation in ossification, especially amongst the carniates and some parrots, clavicles are reduced or even missing. Therefore the apparent absence of clavicles in some theropod dinosaurs may well be due to poor ossification rather than true absence. However, furculas have been found in some theropod dinosaurs, namely the Oviraptorosauria (Barsbold et al. 1990, Bryant & Russell 1993), for example Oviraptor and Ingenia. Thus furculas do not appear to be diagnostic to birds and certain members of the suggested closest group to the birds now appear to possess furculas so it is a neutral character.

------------------
"We shall not yield to you, nor to any man." -- Freak, The Mighty.