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Author
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Topic: evolution vs. creationism: evolution wins
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xevolutionist
Member (Idle past 6953 days) Posts: 189 From: Salem, Oregon, US Joined: 01-13-2005
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Message 181 of 310 (178404)
01-18-2005 11:56 PM
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Reply to: Message 154 by Quetzal
01-18-2005 1:44 PM
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Re: Some concerns about proof
found this, as it turns out, the erroneous conclusion was that it actually walked on it's fins! http://www.geocities.com/.../1427/coelacanth/coelacanth.html
| This message is a reply to: | | | Message 154 by Quetzal, posted 01-18-2005 1:44 PM | | Quetzal has replied |
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crashfrog
Member (Idle past 1497 days) Posts: 19762 From: Silver Spring, MD Joined: 03-20-2003
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Given that they have such a short generation time, is there evidence of bacteria evolving into new, more complex, life forms? Not bacteria, but another kind of unicellular microorganism:
quote:
Coloniality in Chlorella vulgaris Boraas (1983) reported the induction of multicellularity in a strain of Chlorella pyrenoidosa (since reclassified as C. vulgaris) by predation. He was growing the unicellular green alga in the first stage of a two stage continuous culture system as for food for a flagellate predator, Ochromonas sp., that was growing in the second stage. Due to the failure of a pump, flagellates washed back into the first stage. Within five days a colonial form of the Chlorella appeared. It rapidly came to dominate the culture. The colony size ranged from 4 cells to 32 cells. Eventually it stabilized at 8 cells. This colonial form has persisted in culture for about a decade. The new form has been keyed out using a number of algal taxonomic keys. They key out now as being in the genus Coelosphaerium, which is in a different family from Chlorella.
Colonality would be the transitional form between unicellularity and differentiated multicellularity.
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MangyTiger
Member (Idle past 6383 days) Posts: 989 From: Leicester, UK Joined: 07-30-2004
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Re: Some concerns about proof
found this, as it turns out, the erroneous conclusion was that it actually walked on it's fins! I suspected that's what you meant. This was discussed starting at Message 4 (and the last message referencing the coelacanth was 230, but there was a lot of other stuff going on as well). There was a long (and not terribly productive) discussion involving Robert Byers. Message 31 from Percy is perhaps the most significant bit in relation to the current thread :
Robert Byers writes: Whether it was Darwin or his followers it is the history that it was presented as a classic case of a creature that while a fish still had deveoped leglikes that led to its walking on the land. It was presented as proof of a intermidiate creature between land and ocean. The idea of its extinction was a part of their theory. It didn't die out but rather evolved out. That was their great point. Loudmouth has already replied to this, but I'd like to comment on another aspect. It is very common for the theory of evolution to be confused with reconstructions of life's evolutionary past. Reconstructing life's history from the theory of evolution can be likened to reconstructing the solar system's history from the laws of physics. For exaple, we send out space probes to analyze the composition of asteroids, and this information allows as to modify our ideas of the origins of the asteroid belt. But as we change these ideas, the laws of physics remain unchanged. It is the same for the theory of evolution. As we gather more evidence, our ideas about life's history, for example the evolution of the first land animals, changes. But the theory of evolution remains unchanged. Darwin formulated the theory as variability within a population. natural selection, and descent with modification, and today that is still the theory.
Confused ? You will be...
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coffee_addict
Member (Idle past 507 days) Posts: 3645 From: Indianapolis, IN Joined: 03-29-2004
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Message 184 of 310 (178445)
01-19-2005 2:27 AM
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Reply to: Message 174 by Poole
01-18-2005 10:32 PM
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Re: Jacen's Signature
I said it was to relieve stress not to be solved  Now you have ruined it for everybody else. Looks like I'm going to have to put something else down.
Here is something to relieve stress.
Assume that a does not equal b. a + b = t
(a + b)(a - b) = t(a - b)
a - b = at - bt
a - at = b - bt
a - at + t/4 = b - bt + t/4
(a - t/2) = (b - t/2)
a - t/2 = b - t/2
a = b
Since all numbers are the same, math is useless.
| This message is a reply to: | | | Message 174 by Poole, posted 01-18-2005 10:32 PM | | Poole has not replied |
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PaulK
Member Posts: 17828 Joined: 01-10-2003 Member Rating: 2.5
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Re: Some concerns about proof
I have no idea what you are talking about. The Coelocanth is more closely related to the line that lead to the tetrapods than the more common ray-finned fishes and that is true of both the modern and the fossil species. And you still have yet to say which "far-reaching" conclusions are heavily reliant on this partial mandible. It isn't even a particularly significant piece of evidence that tetrapods evolved from fish - the other two speciments you mentioned, as well as some you didn't - are far more important for that.
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PaulK
Member Posts: 17828 Joined: 01-10-2003 Member Rating: 2.5
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Re: Some concerns about proof
Well your original post only tells us that you found the evidnece and then decided to deny that it existed. We still don't know why you would do that.
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Quetzal
Member (Idle past 5902 days) Posts: 3228 Joined: 01-09-2002
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Re: Some concerns about proof
Thanks for the website. Nothing new there, but a couple of great pictures and a nice synopsis (although a bit dated) of the morphology and especially the differences between this critter and most modern fish. Ugly brute, isn't it?
found this, as it turns out, the erroneous conclusion was that it actually walked on it's fins! Unfortunately the website you linked to doesn't support this statement. The only sentence that could even be remotely construed this way is the following: quote:
(snipped discussion of the fin structure) This lobe has it’s own internal skeleton and muscles and the fin rays are restricted to a fan that attaches to the outer end of this lobe (see picture). The lobes give the fish a reptile like appearance and give the idea that the fish might actually be able to walk on its fins. These morphological features lead many scientists to believe the coelacanth lineage was the direct link to tetrapods, but recent molecular evidence suggests that lung fish might be more closely related to tetrapods. (emphasis added)
The author is not saying the fish walked on its fins. He quite clearly states that the idea the critter could "walk" was based on resemblance to critters that DO walk. Not that the Coelacanthidae DID walk. Quite a big difference, no? He even goes on to mention why the idea of coelacanths being ancestral tetrapods is incorrect. So, where is the big "oops" you promised?
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xevolutionist
Member (Idle past 6953 days) Posts: 189 From: Salem, Oregon, US Joined: 01-13-2005
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Message 188 of 310 (178509)
01-19-2005 10:34 AM
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Reply to: Message 168 by crashfrog
01-18-2005 9:32 PM
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sameness
By fundamentally I mean essentially. If inspected with a microscope you would observe no differences. They still live in the same manner, they still have the same morphology, the only difference being that they won't mate with another colony that has a different food source.
Perhaps they don't like their odor. The argument that not being willing to breed with another colony, makes it a different species, seems like stating that since Jennifer Garner refuses to mate with me she must be a different species.
| This message is a reply to: | | | Message 168 by crashfrog, posted 01-18-2005 9:32 PM | | crashfrog has replied |
| Replies to this message: | | | Message 189 by crashfrog, posted 01-19-2005 10:48 AM | | xevolutionist has not replied |
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crashfrog
Member (Idle past 1497 days) Posts: 19762 From: Silver Spring, MD Joined: 03-20-2003
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By fundamentally I mean essentially. But there's no such thing as species essentialism. Species don't contain some kind of "essence" that defines what species they are. A species is just a reproductive community.
If inspected with a microscope you would observe no differences. Oh? You inspected them?
The argument that not being willing to breed with another colony, makes it a different species, seems like stating that since Jennifer Garner refuses to mate with me she must be a different species. If Jennifer Garner wouldn't even recognize you as a potential mate, nor were you able to concieve offspring on her, she would be a different species. If you take issue with the argument then you take issue with the definition of "species". As I said, we stopped believing in species essentialism in the 19th century because there's no such thing as a species' "essence". Didn't you get that memo?
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Loudmouth
Inactive Member
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Re: evidence of evolution
quote:
Given that they have such a short generation time, is there evidence of bacteria evolving into new, more complex, life forms?
No, and they never did. However, they did form a commensal relationship with other unicellular species to form eukaryotes somewhere in our past. Also, there are bacteria that form multicellular colonies in response to starvation. From http://141.150.157.117:8080/prokPUB/chaphtm/188/01_00.htm :
The myxobacteria are Gram-negative, unicellular, gliding bacteria with rod-shaped vegetative cells (Fig. 1) Because of their gliding movement, colonies develop as thin, film-like, spreading swarms, particularly on media low in organic constituents (lean media) (Fig. 2). Under starvation conditions, the myxobacteria undergo an impressive process of cooperative morphogenesis: the vegetative cells aggregate and pile up, and the resulting cell mass differentiates into a fruiting body (Fig. 3). Myxobacterial fruiting bodies show various degrees of complexity, both morphologically and structurally. They typically measure between 50 and 500 m, and they can thus be easily seen with the naked eye. Within the maturing fruiting body, a cellular differentiation takes place during which the vegetative cells convert into short, fat, optically refractile myxospores (Fig. 1 and Fig. 3). The myxospores are desiccation resistant and allow the organism to survive unfavorable environmental conditions. There is also the example of C. vulgaris mentioned earlier, the formation of a mutlicellular colony that breeds true.
| Replies to this message: | | | Message 192 by crashfrog, posted 01-19-2005 12:45 PM | | Loudmouth has not replied |
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Loudmouth
Inactive Member
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Re: Some concerns about proof
quote:
The mosquitos are still mosquitos
Apes and men are still primates . . . Primates and marsupials are still mammals . . . Mammals and reptiles are still land vertebrates . . . Land vertebrates and sea squirts are still chordates . . . I guess you must not have a problem with large scale changes, given you can classify the two species with the same name.
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crashfrog
Member (Idle past 1497 days) Posts: 19762 From: Silver Spring, MD Joined: 03-20-2003
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Message 192 of 310 (178564)
01-19-2005 12:45 PM
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Reply to: Message 190 by Loudmouth
01-19-2005 12:21 PM
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Woah! Your example is way better than mine.
| This message is a reply to: | | | Message 190 by Loudmouth, posted 01-19-2005 12:21 PM | | Loudmouth has not replied |
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xevolutionist
Member (Idle past 6953 days) Posts: 189 From: Salem, Oregon, US Joined: 01-13-2005
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Message 193 of 310 (178650)
01-19-2005 4:50 PM
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Reply to: Message 177 by NosyNed
01-18-2005 10:52 PM
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Re: Some concerns about proof
This article mentions the fact that more than one evolutionist believed that coelacanth walked on it's fins. Since the fins were substantially the same on the living coelacanths, this proves to be yet another erroneous conclusion brought about by wishful thinking. http://www.geocities.com/.../1427/coelacanth/coelacanth.html
| This message is a reply to: | | | Message 177 by NosyNed, posted 01-18-2005 10:52 PM | | NosyNed has replied |
| Replies to this message: | | | Message 195 by NosyNed, posted 01-19-2005 4:58 PM | | xevolutionist has replied |
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xevolutionist
Member (Idle past 6953 days) Posts: 189 From: Salem, Oregon, US Joined: 01-13-2005
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Message 194 of 310 (178651)
01-19-2005 4:53 PM
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Reply to: Message 180 by NosyNed
01-18-2005 11:04 PM
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Re: Ear canals
In conclusion, despite all National Geographic’s best efforts, the fact that there were no transitional forms between land and sea mammals and that they both emerged with their own particular features has not changed. There is no evolutionary link. Robert Carroll accepts this, albeit unwillingly and in evolutionist language: It is not possible to identify a sequence of mesonychids leading directly to whales.[7]
| This message is a reply to: | | | Message 180 by NosyNed, posted 01-18-2005 11:04 PM | | NosyNed has not replied |
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NosyNed
Member Posts: 9004 From: Canada Joined: 04-04-2003
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Walking on fins
This article mentions the fact that more than one evolutionist believed that coelacanth walked on it's fins. Since the fins were substantially the same on the living coelacanths, this proves to be yet another erroneous conclusion brought about by wishful thinking. Would you please quote the precise part that says this?
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