Transitional Fossils Show Evolution in Process

Hi Kaichos Man, still struggling with reality I see Let's run through an analysis of how all the issues that have been raised actually affect the work done by Parker and Arnold.ecophenotypic - one species has a variety of morphological shapes depending on the ecology they are in.morphospecies - one morphological grouping can have several cryptospecies of daughter species that cannot be distinguished based on morphology.ecoclines - differing ecologies similar to thermoclines in water, can be based on temperature, salinity and pressure in various combinations.clinial morphological change - change within a species as subpopulations evolve and adapt to ecoclines and diverge from the parent population.What Parker and Arnold did was to sort through the fossil record and track various morphological types through time:http://web.archive.org/...57/gly.fsu.edu/tour/article_7.html

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We've literally seen hundreds of speciation events," syas Arnold. "This allows us to check for patterns, to determine what exactly is going on. We can quickly tell whether something is a recurring phenomenon--a pattern--or whether it's just an anomally. This way, we cannot only look for the same things that have been observed in living organisms, but we can see just how often these things really happen in the environment over an enormous period of time.

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Geology Dept article 3

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Drs. Tony Arnold (Ph.D., Harvard) and Bill Parker (Ph.D., Chicago) are the developers of what reportedly is the largest, most complete set of data ever compiled on the evolutionary history of an organism. The two scientists have painstakingly pieced together a virtually unbroken fossil record that shows in stunning detail how a single-celled marine organism has evolved during the past 66 million years. Apparently, it's the only fossil record known to science that has no obvious gaps -- no "missing links."

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In other words, based on morpology alone the fossils show a nested hierarchy of descent from common ancestors, with speciation branches showing parent populations giving rise to daughter populations. We can represent one such speciation event roughly as follows:

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Thus we see morphological change from generation to generation, and an overall pattern of descent with modification, and an apparent speciation event at generation "h" -- according to the analysis done by Parker and Arnold.When we look at the concept of morphospecies groups with several cryptic species, what this means for the pattern above is that the speciation event took place earlier, say at generation "f" ...... and when we look at the concept of ecophenotypic variation or ecocline variants, what this means for the pattern above is that the speciation event took place later, say at generation "j" ...... however by the time we get to generation "q" the total change is outside the boundaries of ecophenotypic variation or of ecocline variants, so the classification of lineage is correct at this point.Because the lineages are unbroken in showing morphological change over generations, the issue of when the speciation event actually takes place is of very little impact on the actual hereditary lineages: one could draw a circle around the above lineage to encompass "f" through "j" and label that the speciation event.Thus it can be wrong 15% if the time on when the speciation event/s take place, however the lineage of hereditary descent is unaffected and the overall pattern of multiple speciation events and unbroken hereditary descent is still intact.Enjoy.

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Hi again Kaichos Man, you are still not finding what you need to find. The first question to ask whenever you post something is: does the article really say this?The answer is (as usual) no, as noted by Wounded King: What the article says is that two radiations occurred, and that the second "reproduced nearly the same spectrum of morphologies."We can have the same spectrum of morphologies without a single repetition of a former morphology.For instance, following the trail of the article posted, plus the links from Percy and Wounded King, through the journals and looking for other similar articles (ie - looking to see if this is an isolated instance or a common instance) I find:

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Iterative evolution of digitate planktonic foraminifera
Helen K. Coxall(1,3), Paul A. Wilson(2,3), Paul N. Pearson(1,3) and Philip F. Sexton(2,3)
Paleobiology; November 2007; v. 33; no. 4; p. 495-516; DOI: 10.1666/06034.1 2007 Paleontological Society
http://paleobiol.geoscienceworld.org/...nt/abstract/33/4/495

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Digitate shell morphologies have evolved repeatedly in planktonic foraminifera throughout the Cretaceous and Cenozoic. Digitate species are usually rare in fossil and modern assemblages but show increased abundance and diversity at times during the Cretaceous and middle Eocene. In this paper we discuss the morphology and stratigraphic distribution of digitate planktonic foraminifera and establish the isotopic depth ecology of fossil ones to draw parallels with modern counterparts. δ18O and δ13C values of six extinct and two modern digitate species, from six time slices (Cenomanian, Turonian, Eocene, Miocene, Pleistocene and Holocene) have similar isotopic depth ecologies, consistently registering the most negative δ13C and usually the most positive δ18O compared to coexisting species. These results indicate a similar deep, subthermocline (>150 m) habitat, characterized by lower temperatures, reduced oxygen, and enrichment of dissolved inorganic carbon. This is consistent with water-column plankton studies that provide insight into the depth preferences of the three modern digitate species; in over 70% of observations digitates occurred in nets below 150 m, and down to 2000 m. The correlation between digitate species and subsurface habitats across multiple epochs suggests that elongated chambers were advantageous for survival in a deep mesopelagic habitat, where food is usually scarce. Increased abundance and diversity of digitates in association with some early and mid-Cretaceous oceanic anoxic events, in middle Eocene regions of coastal and equatorial upwelling, and occasionally in some modern upwelling regions, suggests an additional link with episodes of enhanced ocean productivity associated with expansion of the oxygen minimum zone (OMZ). We suggest that the primary function of digitate chambers was as a feeding specialization that increased effective shell size and food gathering efficiency, for survival in a usually food-poor environment, close to the OMZ. Episodes of increased digitate abundance and diversity indicate expansion of the deep-water ecologic opportunity under conditions that were unfavorable to other planktonic species. Our results provide evidence of iterative evolution reflecting common functional constraints on planktonic foraminifera shell morphology within similar subsurface habitats. They also highlight the potential of digitate species to act as indicators of deep watermasses, especially where there was expansion of the OMZ.

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In other words, foraminifera species in similar ecologies can develop similar features in response to the ecological constraints, because those constraints will be the same whether the species is ancient or modern. The same limitations of oxygen, temperature and food will affect different species in much the same way, producing similar results.This is what Percy predicted when he said: And in the article it says:

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The correlation between digitate species and subsurface habitats across multiple epochs suggests that elongated chambers were advantageous for survival in a deep mesopelagic habitat, where food is usually scarce. Increased abundance and diversity of digitates in association with some early and mid-Cretaceous oceanic anoxic events, in middle Eocene regions of coastal and equatorial upwelling, and occasionally in some modern upwelling regions, suggests an additional link with episodes of enhanced ocean productivity associated with expansion of the oxygen minimum zone (OMZ). We suggest that the primary function of digitate chambers was as a feeding specialization that increased effective shell size and food gathering efficiency, for survival in a usually food-poor environment, close to the OMZ.

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Such digitate structures would, of course, be within the spectrum of similar morphologies, while the particular morphologies can still be distinct and varied with the species , genus and family in question.The second question to ask whenever you post something is: if true would this prove your point?Once again the answer is no.To begin with, Globigerinida is not a species classification, but an Order within the Class foraminifera, and thus the radiation would include the formation of superfamilies, families, genera and then species. These groupings can be broken down by their general morphotypic classifications such that all members of the Rotaliporacea superfamily, for example, have similar morphologies. A second radiation that repeats the same general morphology of a superfamily would still be 'nearly the same spectrum of morphologies' without in any way repeating the specific morphologies of the species in each radiation.The third question to ask is whether there is evidence of something else occurring that explains the data better?The answer is yes.We also see that these radiations occurred after extinction events:

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Radiation of Cenozoic Planktonic Foraminifera
Richard Cifelli
Systematic Zoology 1969 18(2):154-168; doi:10.2307/2412601
Radiation of Cenozoic Planktonic Foraminifera | Systematic Biology | Oxford Academic

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The general aspects of planktonic foraminiferal radiation during the Cenozoic are shown by the distributional patterns of several morphotypic groups. There were two major radiations, one occurring during the Paleogene, the other during the Neogene. The radiations followed severe reductions in diversity which occurred at the close of the Cretaceous and again during the mid-Tertiary. Distributional patterns are iterative, and the Neogene radiation is essentially a repetition of what occurred during the Paleogene. According to the present interpretation, the iterative patterns reflect major changes in the dynamic structure of surface waters. By analogy with the distribution of the modern fauna, it is suggested that thermal barriers were degraded during times of reduction and the oceans were uniformly cool. During the radiations thermal gradients were restored and the structure of the surface waters was essentially as it is today.

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So we see extinction events providing opportunity for diversity of remaining species. As the ecoclines are reestablished following these events, we see species inhabiting these ecoclines evolve to take advantage of the opportunities of their habitat. We see these species adapting incrementaly in an iterative pattern to their prefered ecoclines, and finally, we see that these adaptations produce similar general morphological shapes in a spectrum, from say globular to digitate, due to the ecological constraints of the respective habitats. We see that this does not mean that digitate forms from the Neogene are the same as the digitate forms from the Paleogene, nor do we see that they are necessarily the same species because of their shared general morphology.The fourth and final question to ask is whether this affects the data and conclusions of Parker and Arnold?The answer is, once again, no.Using the same analysis we did in Message 109 and extending it to show a morphologically similar spectrum of morphological development, and repeating this basic pattern, we do not see any way that hereditary lineages could be confused, even if the pattern of morphological radiation were very similar:

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Here the pattern from (a) to (q) in gray is repeated in white and attached to the left lineage at (q) resulting in the pattern from (a') to (q'), and an additional pattern of evolution from the right lineage from (q) is shown in orange.The orange lineage cannot be confused with being descendant from the end of the middle branch even though the end result of that branch is similar in form to an ancestral form of the orange lineage.The conclusions from Message 109 remain valid: The continuous nature of the data, sorted layer by sedimentary chronological layer, without breaks, prevents this confusion.This is confirmed by species related to the first radiation that were not involved in the second radiation not being confused with the species related to the second radiation in any of the modern species classifications.Enjoy.

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Hi again Kaichos Man, Percy pretty well nailed it, so I'll just add some side comments to keep us on topic. We know that there was one species at "f" and that there are two species at "j" so therefore a speciation event has occurred between "f" and "j" - and we know that there is hereditary lineage between them because of the morphological study by Parker and Arnold. What we don't know, due to uncertainty about morphospecies, ecophenotypes, cryptic species, ecoclines, and their effect/s, is precisely where between "f" and "j" the actual speciation event takes place.A speciation event is defined as a splitting of the population into two or more reproductively isolated populations, so just a lineage of descent from an ancestral population does not necessarily mean a speciation event has occurred. Often when there is sufficient difference from the ancestral population to be similar to the difference between sibling species, an arbitrary speciation is defined, but there is no singular event to point to for where this occurs.This is what we see with Pelycodus (I've added the color lines, the original image without color lines is fig 10 from Gingerich, P.D. 1976. Paleontology and phylogeny: Patterns of evolution at the species level in early Tertiary mammals, American Journal of Science 276:1-28.): Here we see the evolution of the pelycodus\copelemur\notharctus lineages:

• the red lineage goes from Pelycodus ralstoni to Notharctus venticolus at the upper right;
• in between there is an arbitrary speciation with P.mckennai;
• then a possible speciation event, with P.trigonodus on the red lineage and Copelemur proetutus on the green lineage;
• then an arbitrary speciation to Copelemur feretutus on the green lineage,
• and another arbitrary speciation to Copelemur consortutus on the green lineage;
• back on the red lineage we have another speciation event, with P.abditus on the red lineage with a short lived branch in purple;
• then another speciation event after P.abditus on the red lineage to P.jarrovii on the red lineage and P.frugivorus on the blue lineage;
• finally on the red lineage we see another arbitraty speciation to Notharctus venticolus, which is also given a new (arbitrary) genus classification.

At the top we now have three genera, Copelemur, Pelycodus and Notharctus.Note that each of these fossils are transitional fossils, with each stage showing a range of intermediate forms between ancestral and descendant forms. We also see the formation of a nested hierarchy of common descent, the defining mark of macroevolution. In that case there would be many speciation events, as we know of several lineages that have split off from the hominid line between A. afarensis and H.sapiens.Your circle is so broadly drawn that it covers everything in this image, which shows at least 5 speciation events and 12 species: According to the image on this site there would be at least 10 speciation events:
http://www.handprint.com/LS/ANC/evol.htmlAccording to the image on this site there would also be at least 5 speciation events:
Anthropology | Smithsonian National Museum of Natural HistoryThese images also show transitional fossils, with each stage showing an intermediate form between ancestral and descendant forms. We also see again, the formation of a nested hierarchy of common descent, the defining mark of macroevolution. Well, at least you are consistent - it seems that every point you have tried to make on this thread is overstated to the point of irrelevance. Plus the argument from consequences fallacy. This also seems to be a trend common to other posts you have made, it's like you feel that evolution is wrong, so you have to say something, no matter how silly it is.Enjoy.Edited by RAZD, : • addedEdited by RAZD, : plus

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Hi Kaichos Man, still missing the obvious. Similar to what is found in a gorilla, not OF a gorilla. Surely you are not claiming that "Lucy" was a gorilla now, are you?Curiously, I'm aware of the possible change in status of A.afarensis that is going on, and yet aware that this still does not alter the argument that you have many more speciation events within any circle you can draw that includes A.afarensis with H.sapiens than you do in the example from the foraminifera, and so your argument that they are comparable fails.In the foram example you only have two species on the descendant side and one species on the ancestor side of the circle, and a complete herediary lineage between the ancestor form and either of the descendant forms.Attempting to switch focus from the forams to australopithicus does not alter that simple fact: once again you are guilty of a vast overstatement. Except that none of them show "artist's impressions" ... thus we have another of your blundering overstatements.They show species names with blocks showing hereditary lineage or they show species names with actual skulls showing hereditary lineage. The lineages shown were the best explanation at the time they were made and they have all been updated with new information, it's just that not everyone is in agreement yet on the complete status in those lineages (unlike the situation we have with the foraminifera).They are a great example of science in the process of changing with new information as it comes along. Please note that there are several paths proposed in:Anthropology | Smithsonian National Museum of Natural HistoryAnd that the only difference this status change for A.afarensis could make to the one posted ... (http://www.handprint.com/LS/ANC/evol.html)... is that there would be a branching point outside your overly enthusiastic circle with one branch that would lead from Australopithicus anamensis to A.afarensis on the one hand, and another to the lineage that leads to H.sapiens on the other.Thus this adds more speciation events to your circle and this makes your argument worse.Obviously this does not significantly alter the fact that your circle must include many more speciation events than the situation with the foraminifera branching that you attempted to falsely compare it to. Which you just did again. Sigh.Enjoy.

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Hi Kaichos Man, Curious that the only ancient skulls included in the study are:

• Australopithecus afarensis (two versions) and
• Au.robustus (two versions) also known as Paranthropus robustus

Missing skulls in the comparison are:

• Ardipithecus ramidus
• Australopithecus anamensis
• Australopithecus africanus
• Australopithecus garhi
• Paranthropus aethiopicus
• Paranthropus boisei
• Homo habilis
• Homo rudolfensis
• Homo ergaster and
• Homo erectus
• Homo heidelbergensis and
• Homo neanderthalensis

So we don't see the change in this trait between the time of Australopithecus afarensis and modern primates in the other ancestral species - don't you think that is a little incomplete?Especially considering that the common ancestor between hominids, chimpanzees, gorillas and orangutans is older than the common ancestor between hominids, chimpanzees, and gorillas, while the closest jaw contour to humans is the orangutan? It would seem that this trait may have evolved differently several times, so the intermediate development is more important than the end points. So you pick and use a study as an example that does not have " 'granularity' of the detail" in order to imply that this is missing from the foraminifera lineage?Or is this just another example of your typically overenthusiastic overstatement, rather than any attempt to understand the reality of the fossil record. >>sigh<<Enjoy.Edited by RAZD, : c

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Hi davids-evolution, and welcome to the fray. Are you suggesting that because there is some uncertainty in one area, especially one where new information has been found, that this throws the whole issue of transitional fossils into disarray? Curiously, I don't see your article affecting this issue at all. Perhaps you can explain more. Amusingly, scientists do a lot more than just make lists of differences: if all we had were differences then there would be no tree of life. What is involved is small differences between highly similar organisms, where the similarities show the heredity, and the differences show the evolution.Similar to what we see in life around us today. LOL. This thread is about PRATTs and here we have two more.
CA221: Were you there?
CA220: Evolution replicableThe fundamental problem is that the fossil evidence exists, and thus any attempt to explain the history of life on this planet must explain all this evidence or it is incomplete (at best) or false (at worst).Evolution is one explanation. Every new fossil is a test for the concept that evolution can explain the total known diversity of life. Sadly, for you anyway, this has nothing to do with how evolution and biology actually work. Evolution does not occur in individuals, but in populations. In any event this is not how transitional organisms occur. You are transitional, because you are between your ancestors and your descendants, and you have inherited some traits from your ancestors and some are new from new mutations. Your descendants will\have inherited some traits from you, some from your mate, and some will be acquired from new mutations. Amazingly, it appears you know less about dating methodology and the science behind it than you do about evolution. The good news is that you can learn (I hope) what the science involved is: ignorance is curable by education.If you want to discuss dating methodologies, see Age Correlations and An Old Earth, Version 2 No 1.This thread is about transitional fossils, what they are, and how they actually demonstrate transtions from one form to another through generations of organisms.See Message 3 for examples of transitional fossils.If you want to discuss your incredulity about evolution in general, then I suggest you start a new thread.In the mean time, please consider that not one of your posts on this thread has demonstrated that no transitional fossils occur, or that transitional fossils are not possible, or that you have an alternative explanation that covers all the known facts, evidence, fossils. Thanks, it's always nice to learn new information about the history of life.Enjoy. Edited by RAZD, : last comment.

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Hi davids-evolution, your new here, so you get some leeway to learn. While interesting comments, sadly they have little to do with the topic of this thread -- that transitional fossils exist and that there is abundant evidence for them.On this forum threads have topics, and general discussion that does not focus on the topic interferes with discussion of the topic.We have other threads for IDologists and evolution deniers. This isn't one of them.Please start a new thread to continue, or discuss the topicGo to Proposed New Topics to post new topics.Thank you.

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Hi again davids-evolution, and thanks for the replies on topic. Interestingly I did a google on Dr. Colin Patterson I fully agree with your comments on the lack of direct illustration of evolutionary transitions in my book and this was the first hit:Forbidden This is known as quote-mining, and it is dishonest. Curiously, if creationism were valid then dishonest quote-mines would not be necessary, as there would be evidence to use instead.Now that you know that the site that you garnered this misinformation from was providing you with false information, I trust that you will no longer use it as a source of information.It is also patently absurd that any quote would prove that there are no transitional fossils, when the examples given in Message 3 in fact show transitional fossils. We know for a fact that some transitional fossils do exist in the fossil record, fossils that come between ancestors and descendants in time and that show intermediate traits between ancestors and descendants (note that "intermediate" is a better word than "transitional" and that "transitional" is only used because of past use). Curiously, the fact that you doubt that humans will speciate, in specific, or that any population will speciate in general, after undergoing evolution (through one or more intermediate forms) is totally irrelevant to the issue of being intermediate in time and intermediate in traits between ancestor and descendant populations. You are, de facto a transitional animal. Fascinatingly, you are entirely welcome to your opinion, however opinion in general is completely incapable of altering reality, all it can do is reflect reality, ignorance (not knowing) of reality, or denial of reality, and the only way to tell is by comparing it to reality.Science is not based on the opinions of people, so even the opinions of Patterson, or Osteem, or any other scientist, is irrelevant to what science shows us about reality. Science tests concepts against the evidence of reality, such as the existence of transitional fossils, and discards concepts that are invalidated by the evidence.Enjoy.

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Hi again, davids-evolution, thanks for the reply. So you are saying that putting up a quote that misrepresents a scientist's position is useful in making people reconsider the facts, when the facts before you (again, see Message 3) show that what you quoted is not the real truth. There are in fact transitional fossils.Transitional fossils are a fact of the fossil record, and it is not being dogmatic to point this out. Trying to obfuscate this fact is dishonest. Curiously, you have not shown any evidence that would make one pause, and it is evidence that science uses, not opinions in quotes. You could provide all the quotes in the world, and they will not change the fact that transitional fossils exist in the fossil record. You have used a misquote typical of creationist arguments, and you are full of inuendo that evolution is a false theory, but you are unable to provide evidence, just quotes, and ignored the fact that transitional fossils exist.If you don't want to be viewed as a creationist, then don't wear their clothes. What I want from fellow posters on this forum, regardless of opinion, faith, belief, education, political stripe, etc, is honesty.If you think you have an alternate explanation for the facts then start a new thread. Go to Proposed New Topics to post new topics. If you think it is "essentially unrebutted" then this is a way to test it, a proper way on this forum, rather than hijack a thread that is on a different topic. The topic on this thread is that (a) transitional fossils exist in the fossil record, and (b) that they in fact show evolution - the change in hereditary traits in breeding populations from generation to generation in response to ecological opportunities. So quit whining about getting slapped about misusing a quote, fess up that you made a mistake, to take someones words out of context, and that you didn't have the intellectual curiosity to look into the quote and validate it before posting, and start a new thread on your explanation. You will find a lot of honest response and careful evaluation. Start your new topic, and we will see.In the meantime, perhaps you should look at the evidence shown in Message 3, such as Pelycodus:

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(2) Pelycodus:

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A Smooth Fossil Transition: Pelycodus, a primate

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Pelycodus was a tree-dwelling primate that looked much like a modern lemur. The skull shown is probably 7.5 centimeters long.

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The numbers down the left hand side indicate the depth (in feet) at which each group of fossils was found. As is usual in geology, the diagram gives the data for the deepest (oldest) fossils at the bottom, and the upper (youngest) fossils at the top. The diagram covers about five million years.

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The numbers across the bottom are a measure of body size. Each horizontal line shows the range of sizes that were found at that depth. The dark part of each line shows the average value, and the standard deviation around the average. Then we can discuss whether or not they show forms intermediate between ancestor populations and descendant populations.

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Conclusion

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Clearly transitional fossils exist at the species level, fossils that clearly show the "tiny dawinian steps" from generation to generation.

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Do you not agree?Enjoy.

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Hi Taq, we are getting a bit off topic here, however I wanted to point out one little tid-bit: You are missing his point. Here davids-evolution, who claims we are premature in labeling him a creationist, is making the amusing claim that evolution occurs through the instant generation of hopeful monsters within individual living organisms.Now we return to a discussion of the evidence of transitional forms in the fossil record ...Enjoy.

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