The Nature and Significance of Fossil Intermediary Forms

I'm currently working on an article (thought its difficult, seeing as I cannot work on my PC which has a large amount of helpful resources) on Fossil intermediary forms and their significance. As far as I know, the question of how you identify a transitional is the most relevant question. You can read what I have so far here:http://www.promisoft.100megsdns.com/...aft/transitionals.htm--Some suggestions from evo's on the question of transitionals in the fossil record would be great. What is it you want answered or find is ridiculous regarding the argument?------------------[This message has been edited by TrueCreation, 12-07-2002]

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Sorry, TC, but your essay is filled with strawman versions of evolution to rail against.For example: This is incorrect. Off the cuff, I would prefer to say that the ToE predicts populations will adapt to their environment. If the environment does not change, then natural selection will act to PREVENT change in the phenotype, thus there is no "continuous transition" except in the trivial sense of a record on a non-changing population over time.Here's another: You've just eliminated some of the prime candidates for evolutionary change as outlined by Darwin himself and popularized by Gould. Taken together with this sentence... ... you are eliminating geographic isolation and genetic drift in small populations as potential causes of speciation (and thus transitional fossils).You've basically defined transitional fossils in a way to exclude any possiblity that a fossil will be one. In fossil records where complete records exist of the history of every species and the transitions between them, geographic isolation and local environmental change are always prime factors in speciation.

"Sorry, TC, but your essay is filled with strawman versions of evolution to rail against."
--Well come on, What is included in the article's draft currently is simply things off the top of my head. Mostly resulting from the fact that I havn't come to conclusions yet so they will likely be altered anyways. That it is filled with strawman may be entirely true. I'd just like to correct them. Hence the reason I asked for suggestions/comments in this thread."This is incorrect. Off the cuff, I would prefer to say that the ToE predicts populations will adapt to their environment. If the environment does not change, then natural selection will act to PREVENT change in the phenotype, thus there is no "continuous transition" except in the trivial sense of a record on a non-changing population over time."
--Its incorrect? How so? There is a continuous transition in that every organism is a relative of another's. Whether there are points of static evolutionary progression is irrelevant to the statement. But maybe I should have been more clear?"... you are eliminating geographic isolation and genetic drift in small populations as potential causes of speciation (and thus transitional fossils)."
--This is partially explained in my last sentence:

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These potential inconsistencies can not be considered applicable only in an isolated geographical area, periods of migration and isolations by geological means [land bridges, rivers, etc.]. Evolutionary degenerations such as the loss of flight or hydraulic migration should also be considered in that this may have been the method which was used when the population was translocated or phylognetically split from the original population.

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--But I do think that what you specifically were referring to should be mentioned directly in the article."You've basically defined transitional fossils in a way to exclude any possiblity that a fossil will be one. In fossil records where complete records exist of the history of every species and the transitions between them, geographic isolation and local environmental change are always prime factors in speciation.
"
--Not really. Seeing as I have defined an 'anomaly' as being a fossil of which there is no good quantity of the same species of fossil with the same morphology able to be found within the vicinity of its date. If there are abundant fossils found for the pre-existing species and there is only one or so found for the fossil which would constitute a transition into the next species, of which there are also abundant examples of. If it is shown there is a significant span of time where the transition would occur. Many millions of years or even a few million years, then it is difficult to reason (unless the populations morphology would effect it) that there would be so few examples of the transitional.--What I plan on for the article is pretty blurred right now, but these comments are helping very much.------------------

TC:My take: a transitional fossil ("B") is a member of a species that shares features with fossils of organisms of two other, distinct species ("A") and ("C").
1. Some features in A are found in B
2. Some features in C are found in B
3. A feature present in A and absent in B is absent in C
4. A feature absent in A and present in B is present in CEvolution predicts that some fossils will be transitional with respect to other fossils, and that ordering of fossils believed to be transitional will match the chronological ordering of fossils either forward or in reverse (i.e. ABC or CBA but neither ACB, CAB, BCA nor BAC). The tetrapod lineage shows a lot of these critters, starting with Panderichthys which had both fish and tetrapod features and is found precisely between "fish only" and "amphibian appearance" strata. Another example from slightly later - but still before true amphibians - is Ichthyostega. This critter has fewer "fish" features than Panderichthys, and more "tetrapod" features, but still less tetrapod than, say Acanthostega.What you've got to keep in mind is that there isn't necessarily a direct lineal relationship between the different species we consider transitional. It isn't a series of "begats". It's not a geneology. Evolution predicts that IF tetrapods (for example) evolved from fish, we should at some point find some critter that has features of both located in the relative position in the rocks which are believed to come from the right time frame. And guess what? This is exactly what we find - creationist denial to the contrary.

--Thanks Quetzal, quite well expressed. Though is there anything which contradicts my assertions in the developing article? We do have the appearence of transition all throughout the fossil record, though the nature of the transition itself is what I would place the most emphasis on.------------------

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Originally posted by Miguel:
Darwinism states that live has evolved through small steps over time, but the fossil record doesn't show the necessary level of transitional forms to justify the level of gradualism that Darwinism requires.

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Miguel,What is the "necessary level" of transitional forms?Mark------------------
Occam's razor is not for shaving with.

Miguel,

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Imagine a film. That's the level of transitional forms the very slow and cumulative process of Darwinian evolution requires. Even if we imagine that not all living creatures had left a fossil record, at least some examples of this kind of transition should be evident in the fossil record, considering the astronomical number of live forms that had died. This is not the case.

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Bolds mine.But intermediate/transitionals do exist, rendering your argument moot. The paragraph is very absolutist. You are claiming that intermediate forms don't exist, since you write "this is not the case".Given that they do exist, I ask again, what is the "necessary level" of transitional forms?Mark------------------
Occam's razor is not for shaving with.

"Darwinism states that live has evolved through small steps over time, but the fossil record doesn't show the necessary level of transitional forms to justify the level of gradualism that Darwinism requires. "
--I'm not really going to apply my synopsis to whether it falsifies or presents difficulties for evolutionary theory. Its basically a guideline which will be useful in distinguishing this outside of the article.-------------------

I think Miguel is hinting at what I am trying to get at (hence my considerably old notion that it isn't necessarily the transitional, but the transition). If there are examples of evolutionary transitions from marine to amphibian creatures, how many significant mutative events in the population does this constitute? The timing for the transition is equally important as what the transition is composed of.------------------

Miguel

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Originally posted by Miguel:
Even Darwin recognized this problem. I know darwinism is an ideology, but you don't need to be more darwinistic than Darwin.

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Please respond to post 10.Darwin died over 100 years ago, a lot of new fossils have been found since his day, & according to MJ Benton, the Professor of Vertebrate Palaeontology at Bristol University, the fossil gaps are being filled in at a faster rate than new ones are being created.Intermediates exist, you are claiming that there isn't the "necessary level" of them. I want to know how you quantify such a thing.Mark------------------
Occam's razor is not for shaving with.

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Originally posted by TrueCreation:
I think Miguel is hinting at what I am trying to get at (hence my considerably old notion that it isn't necessarily the transitional, but the transition). If there are examples of evolutionary transitions from marine to amphibian creatures, how many significant mutative events in the population does this constitute? The timing for the transition is equally important as what the transition is composed of.

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If you are discussing 'transitional fossils' why are you
concerned with the 'number of mutative steps' to get from
one to the other?Are you suggesting that for every pair of 'transitionals' there
should be another intermediate?That being the case no wonder creationists are never satisfied,
after all you can divide by two ad infinitum![Added as an after thought]Think of it this way, in any supposed evolutionary chain
we are looking (at each step) at the end result of
an isolation+selection process. To obtain the gradual steps
that led up to each point in the chain would require
a HUGE number of fossils from each intervening year between
the parent and child species.Do you think that is likely with fossilisation?
Even if you had all the bones how much difference
would constitute a 'change' rather than 'natural variability'?The fossil record DOES show tranistional forms, and I'm sure
that most evo's on this site could reel off list after list.Most creationists object by saying 'Ah yes, but what came
in between them two?''Clutching at straws.' springs to mind.[This message has been edited by Peter, 12-19-2002]

Just a general question - is it correct or incorrect to assume that people of African descent (black) arose form the same ancestors as those of non-African (white*)? That is, are all people, regardless of color, derived from the same ancestral human population(s)?[*We are all, ultimately, of African origin, this is just a semi-rhetorical question...]

Miguel,I took issue with you on one point, intermediate fossils. What is the "necessary level" of intermediates for evolution to be supported? Please answer this question.Why people find the explanation that most things that die don't fossilise so unbelievable, I'll never understand. If you check Bentons data, it shows cladistic analyses & stratigraphy improving (overall) as the RCI improves (From data found at http://palaeo.gly.bris.ac.uk/cladestrat/cladestrat.html). That is; the better the fossil record for certain lineages, the greater the correlation of phylogenies & their branching orders, & the appearance of fossils in the rocks). The fossil record supports evolution. Period. Even if there were no intermediates, change over time would still be supported. It simply means that the time resolution of the record isn't good enough to generally spot those changes.Tell me, why else would a good fossil record for a clade return a better stratigraphical match than a poor one?Mark------------------
Occam's razor is not for shaving with.[This message has been edited by mark24, 12-19-2002]

I believe so. But people from all colors are still members of the same species. The differences between them are geneticaly very small. Based on our genes, geneticists say there are no races.M: Based on analysis of many of the same genes differences between humans and chimps are greater than among humans but also relatively small. It increases a bit as you look between humans and gorillas. More between humans and orangutans and so on. If humans arose from a common ancestor based on inheritance of traits i.e. genes, what compelling reason do you have that the same does not hold true among species considering you accept that humans are similar by descent?