Land Mammal to Whale transition: fossils

randman writes:

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It doesn't matter if the whole species evolve or a group evolves, the point is when that species would no longer be able to sexually reproduce with the prior form, assuming one would be present.

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and

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An alternate claim, imo, is that the fossil record does not show the transitions because they did not occur.

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I'm curious, randman, just as a speculative learning exercise in the spirit of your own:1. What fossil findings would demonstrate a speciation event?2. How would one determine reproductive compatibility or lack of same between two contemporaneous fossil forms?Those criteria would be helpful to my learning experience.

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1. What fossil findings would demonstrate a speciation event?

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I have already provided a proposed way to demonstrate this. Now, it could be wrong, but for purposes of this thread, what I asked for were fossils showing the immediate prior species that evolved into the theorized intermediary and the immediate subsequent species.

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In other words, to actually document a speciation event in this transition.

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2. How would one determine reproductive compatibility or lack of same between two contemporaneous fossil forms?

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That's a good question I would hope evolutionists, but for purposes of this discussion perhaps we can start off with are there any credible candidates of this in the fossil record. In other words, if we have nothing even close, then the question is a moot point, which I suspect that it is.

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In other words, you have no criteria with which to identify or rule out the phenomena you insist cannot be found.

Thanks for calling for those numbers, Nosy: I've been fishing for a few of my own, since it first struck me back in Message 41 that 1) events are not fossilized, and 2) we have no criteria for determining species (defined via reproductive compatibility) in the fossil records.Then I started to wonder about randman's claims about the flattening curve of fossil discoveries. My "www" intuitive alert went off, albeit a little late.I follow fossil discoveries as closely as time allows, and it seems to me that the discovery rate is definitely accelerating: hominid discoveries in the past couple of decades have occurred with increasing frequency, and the finds from South America and China are staggering in both number and quality.At first I tried to do my own calculations: how many species to a measured plot of S. American rain forest, how many fossil species found in a measured fossil bed grid, etc., hoping to generate some approximation of how many species might plausibly have lived in a particular past era vs. how many have been found...well, let's just say I decided not to pull numbers out of randman's hat.Here is a useful characterization by Rick Cheel, Professor of Earth Sciences at Brock University in Canada (emphasis added):

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To give you some idea of just how incomplete the fossil record is, consider that 1.5 million different kinds of living animals and plants have been identified on Earth. However, this is not the total number of different plants and animals on Earth, new species are constantly being identified and the total number grows every year.

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Given the current rate at which new species are being identified, it has been estimated that the actual total is on the order of 4.5 million different species of plants and animals. In contrast, the total number of fossil species that have been identified is approximately 130,000. This is only a few percent of the total number of living species. Given that we know from the fossil record that the majority of fossil species are no longer present on Earth, the total number of known fossils is a very small (less than 1%) of the total number of species that have ever lived on Earth.

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Given that the fossil record is extremely sparse when compared to the number of species likely to have existed, the odds of finding a species and the immediately ancestral species and the immediately descended species are astronomical. Of course, that is supposing we could determine those relationships.Finally, for me, the most delectable irony is the reminder that we have not yet found every living species, or even a preponderance of them.This message has been edited by Omnivorous, 08-05-2005 09:07 PM

Nope, not fallacious. You are correct that it could be more precise, and I'll look into those numbers, but basically...*whooosh*that's the sound of hypersonic goal posts passing by...

randman writes:

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OK. So the claim is we don't see speciation events documented because the fossil record is too incomplete.

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Thank you for admitting that we don't see such events documented in the fossil record.

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Nope. Nice obscurantist effort, though: my assertion is that events do not fossilize.The observation was that the fuzzy depiction of one you put forth was 1) astronomically unlikely to be found in the short time we have been digging up fossils, and 2) unverifiable.That is why you defined it that way.

randman writes:

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Are you saying numbers here including bacteria, non-vertibrates, etc,...are relevant and somehow I am moving the goal-posts?

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Please tell me you don't honestly believe that.

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Look randman, let's be frank...well, I'll be frank, you be you.You toss out numbers like a deli ticket wheel, and ignore calls to back them up: '1000 speciation events'...'90% of fossil forms found'...etc.So, why, of course I believe that: the figures relate to a global average. I'm sure your incredulity springs from the same arithmetic I've done: the figures I presented suggest the half dozen or so ancestral species are about what we should have found so far, given that global average.Your tactics are those of a losing chess player: complicate the position whenever possible, and flee simplifying exchanges.I'm happy to dig for more specifically applicable numbers, partly because it will be a genuine learning experience, partly because I suspect it will make my assertion even stronger...but not because I think it will have any impact on you. Your assertions form one amalgamated appeal to consequences--the consequences to your beliefs.The finer grained data--number of extant aquatic species, the number of aquatic fossils found, the surface area of the earth scrutinized to date, the likelihood of salt-sea fossilization--promise to weigh on my side of the scale, not yours. We'll see--though I am sure your arms will wave when I post them.Nite.

NosyNed, how can you separate randman's OP claims about the fossil record's bearing on cetacean evolution from this thread? I'm puzzled.Anyway...randman linked to: "For the most part, this is the case with the entire fossil record. It would appear that the fossil record is very complete, yet there are few, if any possible transitional forms." (quoted text appearing with the graph in the original link...citing this to support his assertion that 90% of the fossil species that will ever be found have been found.I can't find any data points on this curve, randman. Not 90, not 80, not 70...Where did you come up with 90%?This message has been edited by Omnivorous, 08-07-2005 05:52 PM

randman, I'm not one of "you guys"--I'm this guy.There are no data points on that curve, yet you claimed it supported your notion that 90% of fossil species had already been found.But all it illustates is that the more you find of a finite quantity, the less of it there is to find: it is a conceptual graphic, not a data function. Either you have no understanding of the graphic representation of data, or you are debating in bad faith.You asserted that you possessed specific data to support your assertion that we cannot reasonably expect to find additional fossils.You have none.When we plot discoveries of cetacean ancestors, at least there are some data points--in my opinion, more than enough to trace the arc of cetacean evolution. I expect the intervals to be filled as fossil collection moves beyond the readily at hand fields of N. Ameica and Europe to S. America, Africa, Australia, etc.In fact, there is currently a flood of new fossilized species from China and Australia, the former yielding a magnificent proof of avian ancestry, the latter yielding many large mammalian species. S. America is yielding previously unknown 'dinosaur' species.This is not niggling detail. This is a question of your intentional misrepresentation of cited data.I always wondered why people cheat at cards: do they really feel like winners?

Sure:UCSD IT Service Portal - Information TechnologyScroll all the way to to the bottom.Edit: No problem, MangyTiger.This message has been edited by Omnivorous, 08-07-2005 07:29 PM