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trogdor
Skeptic Friend
198 Posts |
 Posted - 04/18/2006 : 17:17:51
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There have only been a few articles posted on the "transitional fossil" page. This makes me sad (any bets on how soon Bill will use this to "prove" that there are no transitional fossils?)
so I've opened the flood gates. Write about anything. Cite. Link. Give pictures. I expect to see some good ones. nylon bug anyone? I want most of the posts here to be articles or comments about those articles. let's stay on task.
(I call CCR5 and AIDS!)
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pleco
SFN Addict
USA
2998 Posts |
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HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 04/18/2006 : 19:22:54 [Permalink]
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That's such a cool mutation, pleco! Certainly, this was a mutation which was beneficial to the bacteria involved, allowing them to digest nylon instead of sugar. But you know, of course, that Creationists will label this as mere "microevolution." They play a silly little game, first insisting that evolution has never been observed, then dismissing every actual scientifically observed example with their catch-all term, "microevolution." In fact, they seem to use this convenient term for all evolution which is observed to be occurring in the present.
"Microevolution" is not a problem of Biblical proportions for the Creationists, because the time scale doesn't directly threaten their interpretation of the Word of God. It would require a time machine to satisfy the phony requirements of the Creationists, as that would be the only way to "directly observe" evolution happening over time scale of eons.
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“Biology is just physics that has begun to smell bad.” —HalfMooner
Here's a link to Moonscape News, and one to its Archive. |
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H. Humbert
SFN Die Hard
USA
4574 Posts |
Posted - 04/18/2006 : 20:07:02 [Permalink]
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quote:
Originally posted by HalfMooner
But you know, of course, that Creationists will label this as mere "microevolution." They play a silly little game, first insisting that evolution has never been observed, then dismissing every actual scientifically observed example with their catch-all term, "microevolution."
As someone once said, accepting microevolution but not macroevolution is the equivalent of accepting inches but then refusing to believe they can add up to miles.
quote:
"Microevolution" is not a problem of Biblical proportions for the Creationists, because the time scale doesn't directly threaten their interpretation of the Word of God. It would require a time machine to satisfy the phony requirements of the Creationists, as that would be the only way to "directly observe" evolution happening over time scale of eons.
Not even then. Creationists would need to see god himself come down and write "Evolution is true" on a stone table. Anything less might be a trick of Satan.
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"A man is his own easiest dupe, for what he wishes to be true he generally believes to be true." --Demosthenes
"The first principle is that you must not fool yourself - and you are the easiest person to fool." --Richard P. Feynman
"Face facts with dignity." --found inside a fortune cookie |
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Ghost_Skeptic
SFN Regular
Canada
510 Posts |
Posted - 04/18/2006 : 23:44:03 [Permalink]
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quote:
Originally posted by H. Humbert
As someone once said, accepting microevolution but not macroevolution is the equivalent of accepting inches but then refusing to believe they can add up to miles.
I think this is exactly one of the intellectual problems that creationists have - they can not understand the implications of large numbers. Therefore they can not understand how with enough generations and a large enough population something as unlikey as benificial mutations becomes inevitable.
I can't think of a better example of evolution thatn the nylon eating bacteria. It is something that happened during our lifetime and definitely qualifies as "macro evolution" since it is such a radical change in an organism which allowed it to take advantage of a change in the environment. |
"You can lead a horse to water but you can't make him drink. / You can send a kid to college but you can't make him think." - B.B. King
History is made by stupid people - The Arrogant Worms
"The greater the ignorance the greater the dogmatism." - William Osler
"Religion is the natural home of the psychopath" - Pat Condell
"The day will come when the mystical generation of Jesus, by the supreme being as his father in the womb of a virgin, will be classed with the fable of the generation of Minerva in the brain of Jupiter" - Thomas Jefferson |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 04/18/2006 : 23:48:44 [Permalink]
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist! 
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Ghost_Skeptic
SFN Regular
Canada
510 Posts |
Posted - 04/18/2006 : 23:54:47 [Permalink]
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quote:
Originally posted by filthy
Stay on topic - we are talking about evolution not devolution. |
"You can lead a horse to water but you can't make him drink. / You can send a kid to college but you can't make him think." - B.B. King
History is made by stupid people - The Arrogant Worms
"The greater the ignorance the greater the dogmatism." - William Osler
"Religion is the natural home of the psychopath" - Pat Condell
"The day will come when the mystical generation of Jesus, by the supreme being as his father in the womb of a virgin, will be classed with the fable of the generation of Minerva in the brain of Jupiter" - Thomas Jefferson |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 04/19/2006 : 01:08:08 [Permalink]
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quote:
Stay on topic - we are talking about evolution not devolution.
There is no such a thing as de-evolution. What you see is what you get but only if you look real quick 'cause evolution never sleeps. Sad, in this case, ain't it? At the rate they're going, we'll soon find ourselves with something brand new but lacking a notochord.
I really don't know if I'm up for researching and writing another of these things, even though an interesting topic comes to mind mind. Gimmie a couple o' days.
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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| Edited by - filthy on 04/19/2006 01:10:13 |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 04/19/2006 : 07:43:30 [Permalink]
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What I habe in mind is going to require a lot of digging. Still dunno if I want to do it. But until then:
C. megalodon was not the direct ancestor of the Great White Shark. This guy was:
Above - 2" upper anterior tooth and 1 3/4" upper anterio-lateral tooth - Isurus (Carcharodon) hastalis - Extinct Mako Shark (Narrow-form) - Middle Miocene (13-15 million years old) - North Carolina, USA. Smooth cutting edge.
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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Siberia
SFN Addict
Brazil
2322 Posts |
Posted - 04/19/2006 : 08:00:41 [Permalink]
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| The horse's, of course! |
"Why are you afraid of something you're not even sure exists?"
- The Kovenant, Via Negativa
"People who don't like their beliefs being laughed at shouldn't have such funny beliefs."
-- unknown
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trogdor
Skeptic Friend
198 Posts |
Posted - 04/19/2006 : 20:07:59 [Permalink]
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As promised, here is my article on CCR5 and AIDS:
First some background information on AIDS. AIDS is caused by a virus, therefore it is not, strictly speaking, a living cell, it is merely a packet of genes inside an outside layer of proteins. Because viruses are not alive, there is new research focusing on them as a transitional form, so to speak between life and non-life.
AIDS attacks its victims like this: a soon as a person becomes infected, the HIV virus begins to attack white blood cells. It does this by prying open one of the white blood cells surface proteins and sending it's DNA inside, that DNA then uses the cells own functions to create more and more HIV viruses. Those viruses then exit the cell to go infect others. By the end of a single day billions of HIV viruses are made.
The HIV virus
HIV attacking a cell
But the human body is not just standing idly by as it is being hijacked by foreign invaders. At the same time as the viruses are multiplying, the immune system is attacking infected white blood cells and killing HIV viruses. (Killing in a vague sense, because the viruses are not actually alive.) How does the virus survive these fierce attacks? They evolve. Because the virus duplicates sloppily, (about 2 mutations per duplication) new strains that are more resistant to the body's defenses evolve quickly and are then quickly spread throughout the body. The immune system has difficulty changing it's attack so quickly and so the virus continues to survive.
This is an interesting image of the evolutionary tree of the HIV virus. Notice how it has jumped to humans from primates several times.
Now it's time to get into the real interesting stuff. Beginning in 1985 Stephen O'Brian looked at the DNA of people who were at high risk of getting AIDS and compared the genes of those who became infected, with those who did not. And he found…nothing. For a long time, until in 1996 when the researchers discovered a fact that I laid out early in this essay, that to get into a cell, the HIV virus needs to rip out a surface protein on white blood cells. That protein, called CCR5 was mutated in some individuals, causing fewer CCR5 proteins, sometimes none at all. People with these mutations can become infected with HIV and not be effected.
Who has these mutations? As opposed to being randomly spread out among the population as one might expect, the mutations are highly concentrated in Europeans and vary few other people have them.
The reason for this mutation is linked to another great epidemic; the Black Death. To create the large percentages of mutation as seen above, there would need to be incredible selective pressures. Selective pressures so great that the people with the mutation would be one of the only ones that survive. This happened during the Black Death. It also matched the area where the mutation is widespread and the time period where the mutation occurred. How the bubonic plague interacted with CCR5 is not yet fully understood. But now, due to great scientific detective work, there is a new idea in the fight against AIDS.
(All the information in this post is from Evolution: the Triumph of an Idea by Carl Zimmer. It is 5 years old and so some info may be outdated.)
also see: understanding evolution
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all eyes were on Ford Prefect. some of them were on stalks.
-Douglas Adams |
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Ghost_Skeptic
SFN Regular
Canada
510 Posts |
Posted - 04/20/2006 : 01:54:27 [Permalink]
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quote:
Originally posted by trogdor
The reason for this mutation is linked to another great epidemic; the Black Death. To create the large percentages of mutation as seen above, there would need to be incredible selective pressures. Selective pressures so great that the people with the mutation would be one of the only ones that survive. This happened during the Black Death. It also matched the area where the mutation is widespread and the time period where the mutation occurred.
Great stuff - It would have been interesting if they had checked for the mutation in the middle east - Israel, Syria, Palestine, Jordan et.c because as I remember, Bubonic Plague was brought to Europe by returning crusaders.
Bubonic Plague is still around with a couple of hundred cases a year in the US - half of them in New Mexico. It is easily treated with antibiotics (for now at least until it evolves resistance). I heard an interview with a guy had gotten it via his dog. The dog picked up infected fleas from a rodent. The dog didn't get sick - I think the fleas don't bite dogs - just rodents and humans. |
"You can lead a horse to water but you can't make him drink. / You can send a kid to college but you can't make him think." - B.B. King
History is made by stupid people - The Arrogant Worms
"The greater the ignorance the greater the dogmatism." - William Osler
"Religion is the natural home of the psychopath" - Pat Condell
"The day will come when the mystical generation of Jesus, by the supreme being as his father in the womb of a virgin, will be classed with the fable of the generation of Minerva in the brain of Jupiter" - Thomas Jefferson |
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 04/20/2006 : 05:58:29 [Permalink]
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Still working on mine. My references list has gotten so long that I'm beginning to think they're breeding when my back is turned. Next I've got to weed it out, then study.....
Why, why, WHY did I start this complicated insanity?!! 
Knew I should'a gone with Crocodiles....
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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filthy
SFN Die Hard
USA
14408 Posts |
Posted - 04/22/2006 : 03:12:16 [Permalink]
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I think I've bitten off a little more than I can chew. I was going to write about the origins of jawed fishes, way back in the Cambrian, but it's tough going because the fossils simply aren't there. It is thought that jaws evolved from front gill arches, but that will have to remain an open question until the rocks settle it.
I dunno. I'll do something with it somewhere/time down the line -- did you know that a hagfish is scarcely a vertebrate at all? Do you care? 
Someone -- might have been Bill -- mentioned trilobites a while back. Those are a interesting group of pretty complex animals, and in my travels, I happened across this link:
quote:
The arms race between predator and prey is a major selective force in evolutionary change in organisms. Operating through decent with modification, nature abounds with examples of the evolutionary arms races: faster predator begets faster prey, stealthier prey begets better scent and sight in the predator, that begets, in turn, better scent and sight in the prey. Bigger, sharper predator teeth begets harder thicker shell in prey; stronger predator poison begets genetic resistance to the poison in the prey -- the list is endless, and examples extend throughout the tree of life.
The life forms that feed upon an organism are just as much a part of the environment to which the organism's population must adapt to survive as are geological conditions, ice ages or meteor strikes, etc. The prey population that fails to adapt to new weapons of the predator, risks its survival. Similarly, the predator population that fails to adapt to new defenses of the prey, risks its survival. In short: "he/she that hesitates (to adapt) is lunch".
quote:
Schizochroal eyes of the Devonian Phacopid trilobite Hollardops merocristata
Each lens has an individual cornea that is
separated from adjacent lenses
quote:
Cambrian Trilobite Altiocculus harrisi with Anomalocaris bite marks from the Wheeler Shale in Utah
So, in place of a real essay, I'll go the easy route and submit trilobites and their defense systems, which are not all that different from those of animals today; just older. A lot older... indeed, the trilobites invented them.
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"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 04/22/2006 : 06:25:14 [Permalink]
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| Being a non-specialist in this sort of thing, I feel like I don't know enough about the topic to have a read favorite. However, one thing that really struck me (and still does, I suppose) is something I learned from our friend Peptide, posted here. It's about HERV's, and is similar to your post, trogdor. |
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Cuneiformist
The Imperfectionist
USA
4955 Posts |
Posted - 04/22/2006 : 06:41:28 [Permalink]
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quote:
Originally posted by trogdor
There have only been a few articles posted on the "transitional fossil" page. This makes me sad
Well, part of the problem, trogdor (for me anyhow) is that in many ways, all fossils are "transitional." My mother, for instance, is, in the slightest of ways, a transition from her parents to me.
If you were to have a fossil preserved from a single line of animals over a span of, say, 200 million years, which one would be the "transitional" one? The answer, of course, is both "all of them" and "none of them" and this is undoubtedly the problem. One could point to an example somewhere between the earliest fossil and the lastest one and call it "transitional." But by the same token, another could simply dismiss it and say that it's not "transitional" but rather just an example of such-and-such creature.
(I see part of this was addressed here, so I won't go on, but that's what I was thinking...) |
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