Summations Only

Actually that's not accurate. The Indian Plate broke away from Madagascar between 90mya and 85mya. The most widely accepted date for contact with the Asia Continent is 55mya, but recent work done here has moved the date back to 65mya. The ocean floor was sliding beneath the Asian Plate during this time, but it was when the land masses came into contact that the Tethys was closing. Perhaps your 50 - 60my was from the break-up of Gondwanaland?Also realize that the Indian Plate was setting a land-speed record (knee slap) moving at 15 - 25 cm per year, covering about 6,000km during that time span. Of course, the collision slowed the advancement of the plate considerably (to about 10cm / year, I believe - it is currently at 5cm / year). At that rate, it would have travelled 1,000km in 10my! So the closing of the Tethys (ie. it no longer existed) would have only taken about 10my and would also have been very violent.So, if you look at the dates for Indohyus, Pakicetus and Ambulocetus they occur concurrently with this closing of the Tethys. If the date of initial contact is in fact 65mya, this compounds the issue. I am not saying this discredits the series, but it is something I think deserves to be to explored. Actually, it could help explain the divergence and diversity we do see.HBD

I am even willing to drop down to 10 million years, but consider even that.

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Evolution could happen because evolution did happen? Circular reasoning.

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My question is not so much "could" it happen as "did" it happen. I am not questioning evolution in the traditional sense. I am only trying to make sense of it. For the most part I accept evolution, but I don't just "believe" because of a well placed "series". I need to examine it and decide for myself if the evidence is sufficient. That's what we should all be doing, correct?

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This is what you said: "Could evolution have caused such rapid changes among contemporary species?"So you were asking whether evolution COULD happen in such a short period of time (if whale evolution did take a short period of time), and I answered it. By now claiming that my answer is insufficient because it does not show that evolution DID happen, is artificially moving the goal posts.A well-placed series is a strong confirmation of the predictions of evolution. Looking at the family tree produced by comparing the genes of different organism, we know that whales most likely evolved from land mammals. The fact that we find transitionals at all is evidence for evolution, the fact that we find them in a general series, before we see whales makes it even stronger. It confirms the predictions evolution makes, and totally makes sense if evolution is true.However, a well-placed series is not the only evidence for whale evolution. Vestigial body parts, the cattle rumen in the stomach, atavistic body parts, and embryonic body parts also support evolution.

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True. But those dates don't necessarily tell you when the species started, only when that particular animal lived. Can it be logically deduced that was one of the earliest specimens? Especially when a sister group is significantly older.

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Right, they are only approximations, which is one reason why, if evolution is true, we see only a general trend from less whale-like to more whale-like, especially when we leave out species we don't have a lot of data on. However, it is still the best approximation we have, and see still see a trend.

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I also question using Wikipedia as a source. It is just not reliable.

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That statement in itself is not reliable. Wikipedia is mostly reliable, and most of its mistakes are minor. So can you present the sources that YOU used?

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I am also uncertain as to why these creatures would be adapting more and more to life in the water when India was crashing into the continent, closing the Tethys and pushing up the himalayas. Any insights here?

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Continental drift takes long periods of time, so whales still had a large area to evolve in. Plus you are assuming that whales did not diversify to areas different than where the Indian subcontinent was meeting Asia.

Hi dan4reason, herebedragons, etc. Another thing to point out is that evolution predicts an increase in evolution of diversity where survival pressure is low, such as when a species moves into a new ecosystem with little opposing forces, or after a massive die-off. This is because there is less selection overall and this allows a greater diversity in phenotypes. It also leads to rapid speciation when pockets of parent populations breed more within a subpopulation than the whole population due to dispersal into the ecology -- distance is a barrier to breeding from one side of the population to the other.Is there any evidence of this actually happening? Yes. The foraminifera experienced an "explosion" in new species following the Y-T extinction event.Then there is the issue of diversity within a species, and whether or not two fossils could overlap in phenotype variation given the dates and locations and the differences in the fossils.See Dogs will be Dogs will be ??? for a discussion of what I mean here. In essence the variation known in dogs today, while still being one species, shows a large degree of variation in phenotypes that can then be used to compare the degree of differences between fossils (horses are used in the thread cited) to see if that is the same degree of difference or not.You can also look at the variation at each level and how much they overlap the variations of each previous generation in pelycodus (previously discussed): We see that the average change from generation to generation is less than the variation in the population, but by the time you get from Pelycodus ralstoni to Pelycodus jarrovii the whole population has shifted.Enjoy.

You can't isolate a quote and answer just that, you need to consider the context. Let's look at what I actually said:

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I think this shows the organisms in this series were contemporaries living in pretty much the same area. It is worthwhile to question whether this could actually represent a clear transition. Could evolution have caused such rapid changes among contemporary species?

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The context was that these animals were contemporaries living in the same area. Answering that with "humans evolved in 8my" did not respond to concerns. If you want to put the goalposts back where to you think they were and declare victory, I don't care. The real victor is the one who learns! We both know that Wikipedia is not considered a scholarly source. It is OK to use for general information and a starting place to find facts. One of the reasons I have come to this forum is so I can have intelligent, educated discussions about these topics. I want to go deeper than "Wikipedia" discussions. Don't you? I did that: http://www.paleodb.org/cgi-bin/bridge.pl
http://sims.ess.ucla.edu/PDF/Ding_et_al_Tectonics_2005.pdfanything else that I needed to cite? Read some of my other posts (even just those on this thread). I am clearly not anti-evolution. If you came here to beat-up on creationists, I am not that guy. But neither am I an atheist. As I stand somewhere in the middle, I am not adamant about any specific issue. If a piece of evolutionary theory falls, so what. If a piece of evolutionary theory stands, that's fine too. As long as either way, it is the truth.Evolutionary relationships are questioned all the time. New evidence and new fossil finds can completely rearrange thinking about the evolutionary process (not the general processes, but the specifics). Such an upheaval has happened recently in the origin of mammals. Finds in Australia have challenged the long held view that mammals originated in northern Lurasia and later made their way south. I presented evidence in this thread Message 61 that India closed the Tethys 10my earlier than previously thought. I think this poses a challenge to the currently held view of Cetatian evolution. This is NOT my position. Call it an observation, an hypothesis if you will. A discussion topic. And you are assuming that they did? How is that any different? The evidence that they diversified is not the end result. If we don't know how they went from point A to point B then we simply don't know. So what is the evidence that they diversified? The commonly held theory is that whales evolved in the Tethys, but how did they evolve in the Tethys when the Tethys was closed? These are the types of things I am looking to discuss - not whether "evolution is true".I hope this clears up the misunderstanding of my intentions and reasons for bringing this issue up.HBDEdited by AdminModulous, : Changed url from http://%20http//paleodb.org/cgi-bin/bridge.pl to its present form.

I really like the website you got your image from. I looked around a bit and he has certainly done a lot of work.We certainly don't have the resolution in the Cetacean record that we do in Pelycodus. How does the amount of change from P. ralstoni to N.nunienus / N. venticolis compare to that of the Cetacean series? It covers about the same time span. Could you expand on this a bit? Are you saying that a reduction in selection pressure allows increased diversity within a population? Which then allows increased opportunities for speciation?How could we apply this to the whale series?HBD

Hi again herebedragons, I agree that we don't have the resolution in the Cetacean record that we do in Pelycodus, the Cetacean record is more like stepping stones along a path, while Pelycodus is more like a paved stone walkway. The question is whether new fossils (paving stones) fill in the walkway or branch off the path. One thing to remember about evolution is that the time metric is measured in generations, rather than years, and that average offspring per generation can condense one lineage compared to another by introducing more variation per generation. This would likely mean that pelycodus has more opportunity for diversity than the cetaceans on both counts.The other thing to remember is that selection is in response to ecological opportunities and challenges. In the mature ecosystem of pelycodus there is less opportunity and more challenge for added diversity, so this slows down the process. It is only as the whole population moves gradually towards larger individuals that an opportunity is made for a smaller species to survive. Looking closely at the pelycodus chart there are a couple of short branches towards smaller species, but they die out: not sufficient opportunity to survive. The opportunity for a smaller species only occurs once the main population is pretty much all larger than the ancestral (P. ralstoni) species was.In an open ecosystem there would more opportunity and less challenge. Yes, reduced selection pressure means that more of the population survives to breed, including more of the ones with diverse variations compared to the parent population, thus resulting in greater diversity in the whole population. As population size increases it also becomes more difficult for all genes to spread equally through the population, so you develop varieties in different areas, especially when subpopulations live in slightly different ecologies (shallow vs deep ocean).The fossil evidence of foraminifera (another case where we have a paved walkway vs stepping stones) shows us that this in fact happened after the K-T extinction event:

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A Classic Tale of Transition

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It may be in what the foram record suggests about how life copes with Mother Earth's periodic bouts with annihilation that eventually draws the most attention to Arnold's and Parker's work. The geologic record has been prominently scarred by a series of global cataclysms of unknown, yet hotly debated, origin. Each event, whether rapid or slow, wreaked wholesale carnage on the planet's ecology, wiping out countless species that had taken nature millions of years to produce. Biologists have always wondered how life bounces back after such sweeping devastation.

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One of the last great extinctions occurred roughly 66 million years ago, and according to one popular theory it resulted from Earth's receiving a direct hit from a large asteroid. Whatever the cause, the event proved to be the dinosaurs' coup de grace, and also wiped out a good portion of Earth's marine life -- including almost all species of planktonic forams.

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As revealed by the ancient record left by the foram family, the story of recovery after extinction is every bit as busy and colorful as some scientists have long suspected.

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"What we've found suggests that the rate of speciation increases dramatically in a biological vacuum," Parker said. "After the Cretaceous extinction, the few surviving foram species began rapidly propagating into new species, and for the first time we're able to see just how this happens, and how fast."

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As foram survivors rush to occupy their new habitats, they seem to start experimenting will all sorts of body shapes, trying to find something stable, something that will work, Arnold said. Once a population in a given habitat develops a shape or other characteristic that stands up to the environment, suddenly the organisms begin to coalesce around what becomes a standardized form, the signature of a new species.

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As the available niches begin to fill up with these new creatures, the speciation rate begins to slow down, and pressure from competition between species appears to bear down in earnest. The extinction rate then rises accordingly.

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There is no reason to think that this is an isolated incident applicable only to foraminifera. They were moving into a new ecosystem that was also impacted by, and still recovering from, the K-T extinction, and they had few competitors amidst an ecosystem of opportunity. Whale evolution would logically have diversified rapidly into a variety of forms that then gradually honed in on specific adaptations to different aspects of the ecosystem, baleen vs toothed, etc.Enjoy.

Actually, there is no claim that any of the animal species depicted in the cladogram evolved into any other species depicted. In fact, the cladogram indicates that this is probably not the case. The "transitional diagrams" used in cladistics (called cladograms) indicate relationships between lineages, not ancestry. The implication is that the lineages share an ancestor. But no such claim is made. They are placed next to each other based on very good anatomical evidence, geographic evidence. The thought was that the Mesonychids (a sub-order) shared an ancestor with Pakicetus. More recent research indicates that cetaceans are more likely to share an ancestor with another non-mesonychid artiodactyl.By the way, there is one characteristic that is common to all of these organisms that exists only in whales, i.e., cetaceans. That is a sure-fire sign that they are related somehow.

Since this was the cause to some heated discussion I had taken the time to investigate this particular case. Unfortunately I could not find the true origin of this quote/reference but as I stated before this was most likely that the reference provided did not match the quote.

In any case, here is some reading material that seems to make the same statement:

Investigating species boundaries in the Giliopsis group of Ipomopsis (Polemoniaceae): Strong discordance among molecular and morphological markers: http://www.amjbot.org/content/96/4/853.full

Discordances between morphological systematics and molecular taxonomy in the stem line of equids: A review of the case of taxonomy of genus Equus: http://www.journals.elsevierhealth.com/...311003362/abstract

Hello. Is your argument now distilled down to a google inquiry on the term discordance in regard to science publications?

They really don't make the same mistake, something that I attribute to them being actually written by real scientists.The papers sort out minor discrepancies. However, equids remain a clade, as does Gilopsis. They're sorting out the fine details. Such papers can give cold comfort to anyone who wants to claim that things that anatomically are whales wouldn't be so genetically.If these two weren't particularly genetically similar, then something fairly strange would be going on ... ... especially as we can find greater morphological divergence within modern forms which are by every molecular test whales.In the absence of DNA from Dorudon, which way would you bet?But in any case, in the absence of DNA we do what we can without it. The theory of evolution tells us that we should be able to find intermediate forms if we look long and thoroughly enough. We looked long and thoroughly enough, and we found intermediate forms. The theory does not tell us that we should be able to apply the techniques of molecular phylogeny to fossils millions of years old, and sure enough, we can't. We see what biologists say we should be able to see. The fact that you can fantasize that the evidence we don't have and can't have might contradict the evidence we do have is neither here nor there.One would not recommend such a tactic to a defense attorney: "OK, the blood-stains, the fingerprints, the gunpowder residue all point towards my client's guilt ... but if the concrete floor of the crime scene had been soft mud instead so that footprints could have been left in it, those footprints that aren't there in the concrete that couldn't receive their impressions might have told quite a different story." Well, this is neither here nor there.Going by the evidence we have, we have less-derived whales in the fossil record.

I found this and looks like it belongs in this thread.

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Terry Mortenson and Whale Evolution

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At the conference, Terry Mortenson of Answers in Genesis represented the young earth view. While I was there, I picked up several of their videos.

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In one of them, Dr. Mortenson brings up Pakicetus, a species considered by most to be an ancestor of whales. He quotes Dr. Philip Gingerich, one of the leading experts on the evolution of whales as saying that Pakicetus is quote "an important transitional form linking Paleocene carnivorous land mammals and later, more advance marine whales."

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He then shows a slide of the fossil evidence at that time, which included only parts of the skull. This is the screenshot of the slide, which is taken from the Journal of Geological Education:

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Dr. Mortenson presents this slide as though it is laughable that they built a whole species from so little in the way of fossils. He shows another slide with a drawing of Pakicetus as a dweller in shallow water that turned out to be a highly inaccurate drawing. Later findings showed Pakicetus to be a land animal.

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What's dishonest about this?

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Look again at the bones that were found in the diagram above. Do you notice that it includes the bones of the ear? Cetacean (whale) earbones are unique among all mammals. Consider this quote: When Gingerich looked underneath the skull, he saw ear bones. They were two shells shaped like a pair of grapes and were anchored to the skull by bones in the shape of an S. For a paleontologist like Gingrich, these ear bones were a shock. Only the ear bones of whales have such a structure; no other vertebrate possesses them. (Carl Zimmer. I'm not sure the quote is referring specifically to Pakicetus, but the point is that cetacean ear bones are unique.)

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It really wasn't worth mentioning that Pakicetus has this unique ear bone structure? It wasn't worth mentioning that this explains why Dr. Gingerich was leaping to conclusions based on a jawbone and part of the skull? It wasn't worth mentioning that there is an entire lineage of fossils with this ear structure, fossils progressing in time, fossils which become more and more marine, and in which the nostrils slowly progress up the skull from its front to its top?

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It wasn't worth mentioning any of this, just showing a slide giving an impression that really isn't accurate?

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In the context of this page, the truth is that creationists devote their time to finding inaccurate potshots like this.

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Why Creationists Win Evolution Debates

Just so you know, the beginning of an answer to one aspect of your proposed A holistic understanding on the evolution belief system has been posted at Explaining the pro-Evolution position , and that it addresses the issue of what evolution science IS -- a science, not a belief system.Curiously I read your proposed topic and was struck by how little it pertained to evolution science, and rather was attacking a creationist straw man that characterizes all science and humanistic or materialistic beliefs under the banner of "evolutionism" as if calling it an 'ism' makes it a belief system that unites these different elements. It doesn't.For instance morals and what is "good" and what is "bad" -- science studies what happens in the physical testable world, and does not make judgements like that, rather that falls under philosophy (like humanism or materialism), and if you want to discuss this further I can open another new thread to that effect. Or you can proceed as admin suggests.No reply here please, you can message me.Enjoy

So, from the responses it seems as if you, TheArtist, didn't tell the truth about what was found in the pre-whale fossils.Edited by Pressie, : No reason given.

So, basically, you didn't tell the truth?