Transitional Fossils Show Evolution in Process

What better way to choose someone's path than by denying them a choice of paths?

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"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

Hi Kaichos Man,You're adding more off-topic commentary to a subthread where people were making an effort to coax Sailorstide back onto the topic. If you want to post messages not about fossils but instead about teaching religion in public school science classrooms then you should raise the issue in threads where it would be on topic. Or you could propose your own topic over in Proposed New Topics. Thanks.--Percy

Hi Kaichos Man,Here's a link to the article by Pawlowski and Holzmann whose abstract you quoted from: Where does it say anything supporting your claim that Arnold and Parker confused morphological differences with species differences?You appear to be taking your argument (and your image) from The Fossil Record: Foraminifers by Sean D. Pitman M.D. Why don't you cite your sources and throw this guy, and Pawlowski and Holzmann, too, some credit?If Pitman or Pawlowski and Holzmann have any arguments against the Foraminifers as an example of a continuous fossil record of evolutionary change then you haven't reproduced them here in a way that makes any sense. We understand the ecophynotypic argument, but you never show how Arnold and Parker committed that particular mistake.--Percy

Hi Kaichos Man - still reading more into information than is there? There are a couple of problems here. Notice at the right edge of your graphic there is a group labeled "planktonic" and the rest are all benthic.Your article applies to benthic forms:

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The diversity and distribution of modern benthic foraminifera has been extensively studied in order to aid the paleoecological interpretation of their fossil record.

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While Arnold and Parker studied planktonic: Evolution at Sea

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Tropical and subtropical seas around the globe abound with forams, which are divided into two general types: The free-floating, planktonic form that is uniformly small (usually less than a 50th of an inch long) and the benthic or bottom-dwelling variety that is typically much larger. The later type is perhaps best remembered by Earth-science students or by spelunkers who commonly find the fossils imbedded in cave walls. The ancient Egyptians used limestone blocks containing the large, extinct Nummulites to build the tops of some Giza pyramids.

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But it's the planktonic variety that chiefly interests Parker and Arnold. Unlike their oversized cousins, free-swimming forams are found almost everywhere in the oceans. Their fossilized skeletons, in fact, were among some of the first biological material recovered from deep ocean bottoms by scientists in the 1850s. For nearly a century, geologists have used the tiny fossils to help establish the age of sediments and to gain insight into prehistoric climates.

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So the free floating ones are not bound by the ecological constraints of their local environment the way the benthic ones are.Furthermore, your article only covers two groups of benthic forams:http://www.springerlink.com/content/83502273g54060w5

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... Here, we present two examples of the use of DNA sequences to examine the diversity of benthic foraminifera. The first case deals with molecular and morphological variations in the well-known and common calcareous genus Ammonia. The second case presents molecular diversity in the poorly documented group of monothalamous (single-chambered) foraminifera. Both examples perfectly illustrate high cryptic diversity revealed in almost all molecular studies. ...

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However, similar studies have been done on the planktonic forams with similar results of finding cryptic species.Foraminifera - Wikipedia

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Modern forams are primarily marine, although some can survive in brackish conditions.[4] A few species survive in fresh water and one even lives in damp rainforest soil. They are most commonly benthic, and about 40 morphospecies are planktonic.[1] This count may however represent only a fraction of actual diversity, since many genetically discrepant species may be morphologically indistinguishable.[5]

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[5]^ Kucera, M.; Darling, K.F. (2002). "Genetic diversity among modern planktonic foraminifer species: its effect on paleoceanographic reconstructions". Philosophical Transactions of the Royal Society of London A360 (4): 695—718.

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Where "morphospecies" are species groups defined by their morphology, while understanding that there may be one or more cryptic genetic species involved. This means there are possibly more species, but it is difficult to say because they look the same.So finally, there is the problem of what the evidence actually shows, versus what you claimed: You have it exactly backwards -- the cryptic forams were wearing the "same coats" while exhibiting greater diversity under those "coats" (tests).At worst this means that where Arnold and Parker saw some speciation events, they may have missed others due to crypsis, and this in no way invalidates the speciation events seen, nor does it invalidate the panorama of transitional forms for the planktonic forams. Classifying forams by their tests ("coats") underestimates the diversity, but does not invalidate the fossil record of change in breeding population from generation to generation.Enjoy

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Well put and of course that is why the intelligent design folks keep dragging out yet another example of "irreducible complexity" each time someone dismantles the previous example. Almost reminiscent of the much discredited "Gish Gallop" argumentation technique.
Index.php - RationalWikiAnd of course "irreducible complexity" is really a variation of the "no transitional fossils" claim by the traditional YECers. Which is exactly why in my opinion there is not really a dime's worth of difference between a YECer and an IDer.

Further to the previous reply, the article cited can be found here: Cryptic species of planktonic foraminifera: thier effect on paleoceanographic reconstructions, by Kucera, M., and Darling, K.F., 2002.Bits and pieces from the article:

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(abstract)Shells of planktonic foraminifera recovered from marine sediments provide a multitude of important palaeoproxies. Most of these proxies are based on the assumption that each morphospecies of planktonic foraminifera represents a genetically continuous species with a unique habitat. ... To date, 33 cryptic genetic types were found in 9 out of the 22 sequenced morphospecies of modern planktonic foraminifera. An examination of this database suggests that cryptic genetic diversity may be a prevalent pattern among modern planktonic foraminifera, but that the total number of cryptic genetic types per morphospecies is not large and that most genetic types show a non-random pattern of distribution in the oceans. ... Trials with arti cial neural networks (ANNs), the modern analogue technique and Imbrie{Kipp transfer functions showed that the splitting of G. bulloides into three genetic types resulted in substantial reduction in the prediction error rate (by 5 to 34%) and that this improvement was by far greatest in ANN trials (on average more than 20%). We conclude that such a large reduction in error rate occurred because the models resonated with a real pattern in the original data. This study indicates that genetic diversity among planktonic foraminifera may become more of a gift than malaise to palaeoproxies. If it becomes possible to distinguish these genetic types in the fossil record, the accuracy of proxies based on planktonic foraminifera will indeed substantially increase.

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Individual species of planktonic foraminifera differ substantially in environmental preferences, physiology, feeding, behaviour and reproduction (see, for example, Hemleben et al . 1989). These parameters exert direct influence on their spatial and temporal distribution in the oceans and on the shape and chemistry of their shells. Therefore, most proxies derived from planktonic foraminifera require species-specific calibration (Spero et al . 1997; Bemis et al . 2000; Bijma et al . 1998). Consequently, the recent discovery of cryptic genetic diversity in modern planktonic foraminifera (Huber et al. 1997; Darling et al . 1999, 2000; de Vargas et al . 1999, 2001) has potentially significant repercussions for such palaeoproxies. There is growing evidence that these cryptic genetic types are ecologically different (Huber et al . 1997; Darling et al . 1999, 2000; de Vargas et al . 1999, 2001; Stewart et al . 2001). This means that all palaeoceanographic proxies may have been in fact based on aggregates of ecologically distinct populations and may therefore contain significant noise, if not error (Darling et al . 2000).

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On the other hand, the discovery of this hidden diversity may help to elucidate patterns of distribution in certain modern species that could not be easily explained by assuming that these represented ecologically unique entities (see, for example, Hilbrecht 1997). It also holds great promise for improving the accuracy and reliability of foraminiferal proxies. For example, sea-surface temperature (SST) reconstruction techniques based on planktonic foraminifer species abundances seem to be limited in their precision to an average prediction error rate of ca. 1 C (Malmgren et al . 2001). ....
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Diagnosis of modern planktonic foraminifer species is based almost entirely on the morphology of their shells. Biological observations have been used mainly to validate the morphologically de ned taxa (Hemleben et al . 1989). Although a significant morphological variation has been described within these morphospecies (i.e. species whose diagnostic concept is based on morphological features), the exact significance of the observed differences has not been fully understood and the various morphotypes were treated as ecophenotypic variants (Ericson 1959; Kennett 1968a; b; Frerichs et al . 1972; Malmgren & Kennett 1972, 1976; Hecht et al . 1976).

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Recent molecular studies (Darling et al . 1999, 2000; de Vargas et al. 1999 , 2001) have demonstrated that many of the traditionally identified planktonic foraminifer species consist of complexes of genetically distinct types. All genotypes were characterized by sequencing typically 1000 base pair (bp) fragments of the SSU rRNA gene. Within each genetic type, all specimens are identical across the entire sequenced fragment. Between the genotypes, a significant number of differences can be observed (see, for example, Darling et al . 1999, 2000; de Vargas et al . 1999, 2001). This discovery allows a completely new look at the species concept in this group and reveals a new possible explanation for the large variability within traditional morphospecies.

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The genetic types are likely to represent cryptic sibling species, a commonly observed phenomenon among marine organisms (Knowlton 1993), where species level differences are not obvious from morphology alone. The term `cryptic species’ is commonly used to refer to morphologically identical forms distinguished only by genetic, physiological or behavioural differences compared with `pseudo-siblings’ or `pseudo-cryptic species’ (sensu Knowlton 1993) where a potentially high degree of underlying genetic variation is reflected only by recondite morphological alterations, often previously unnoticed or ascribed to ecophenotypic variation. In the absence of conclusive evidence that these genetic types can be differentiated on morphological grounds, we use the term `cryptic species’ to denote genetically distinct types within the traditionally recognized morphospecies of modern planktonic foraminifera.
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The compilation of all data published or otherwise presented to date (table 1, gure 1) clearly suggests that cryptic genetic diversity is a persistent pattern among modern planktonic foraminifera. Distinct genetic types have so far been recognized in nine morphospecies, but it appears likely that extensive studies will identify such genetic types in most, if not all of the traditionally recognized modern species. It is also clear that these cryptic genetic types show distinct patterns of distribution in the ocean (table 1) and that it is highly likely that they in fact represent distinct biological species.

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Although the potential benefit of the genetic diversity of planktonic foraminifera for palaeoproxies has been demonstrated more convincingly in this study, one major obstacle to the realization of this potential remains. The genetic diversity must be translated into morphological features so that the genetic types will no longer need the label `cryptic’ and it will become possible to differentiate at least some of them in the fossil record. Huber et al . (1997) and de Vargas et al . (2001) provided the rst evidence that the large `phenotypic’ morphological variability observed in modern species might indeed be linked to genetic differences. The challenge ahead is to expand these studies, including all of the known genetic types, and develop effective and useful criteria for their morphological discrimination.

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Things to note:

1. Individual species of planktonic foraminifera differ substantially in environmental preferences, physiology, feeding, behaviour and reproduction.
2. Recent discovery of cryptic genetic diversity in modern planktonic foraminifera shows that ~ 2 to 6 genetic types have previuosly been lumped into one species by morphology, creating what is called a morphospecies.
3. The genetic types likely represent cryptic sibling species, a commonly observed phenomenon among marine organisms.
4. These cryptic species also seem to differ in environmental preferences, physiology, feeding, behaviour and reproduction -- ie behave biologically as different species.
5. Some of the variation seen within the different morphospecies can be explained by the different genetic types, and this can lead to differentiating these genetic species on a morphological basis.
6. Similar differentiation may be possible in the fossil record to differentiate between sibling species by fine tuning the morphological groupings -- ie using splitter rather than lumper classifications, but still along the lines of what Arnold and Parker have already done.

None of this recent work invalidates the fossil record showing lineages of common descent with changes in morphology over time, nor does it invalidate the observed division of parent populations into reproductively isolated daughter populations, rather this new work reinforces this pattern and extends it to a finer detail in the living species. This same level of detail may not be discernible in the fossil record, yet we can assume that it exists or not, and the pattern of common descent still holds, locked in the fossils, evidence of intermediate forms between ancestral and descendants, evidence of evolution in process: forams are indeed transitional fossils, as the term is used in science.Enjoy.Edited by RAZD, : more linksEdited by RAZD, : glitch fixed

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Ah, RAZD.I bring up "ecophenotypes", a single species exhibiting a range of morphotypes. Then you bring up "morphospecies", which can be several species exhibiting the same morphotype- and accuse me of having it the wrong way around!The fact is, forams are extraordinarily plastic. They possess, as you have pointed out, "cryptic genetic variation". It may be worthwhile to establish exactly what that means:

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What is cryptic genetic variation? Cryptic genetic
variation refers to unexpressed, bottled-up genetic
potential. It is not normally seen, but is expressed
under abnormal conditions such as in a new environment or
a different genetic background. In a sense, the
measurable component of normal variation is just the tip
of an iceberg of genetic possibilities that are hidden
below the visible surface.

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Gibson and Reed 2008

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Notice that this doesn't make them seperate species. It means a single species can take many forms. This results in ecophenotypes and morphospecies. It means that when you look at three morphotypes you could be looking at six species or one. And the fact is, it's impossible to tell:

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Alternatively, due to the lack of paleoenvironmental and
biogeographic observations in the past, it cannot be
discounted that all morphotypes found in this
investigation simply represent ecovariants of one
species.

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Knappertsbusch 2000

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The cryptic genetic diversity of living foraminifera has been established through molecular studies. But the forams comprising the fossil record contain no DNA. That's why Arnold and Parker had to rely on microphotography.And given that -at any given time- they could be looking at the same species taking several forms, or a single form representing several species, their claims of establishing an unbroken evolutionary progression are laughable.

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"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

Wouldn't it be great if you could establish that by argument rather than by confident assertion?

Hi, Kaichos Man.Welcome back! It's good to you(r words) again. You're confused, Kaichos Man. Look at your quote again: It says morphology underestimates diversity. There is more diversity than morphology would suggest. That does not mean "the same critters wearing different coats"; that means, "different critters wearing the same coat."There is nothing here that suggests that there is ecophenotypic diversity in forams.

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-Bluejay (a.k.a. Mantis, Thylacosmilus)Darwin loves you.

Hi Kaichos Man, you will be pleased to know that I gave your post serious consideration. I'm going to go long on you, because you deserve it.When you first posted the question about ecophenotypes I noticed that you provided no evidence to link the term to foraminifera other than your claim. Previous experience with your claims leaves this a questionable source of authority at best. It seemed fairly obvious to me that you had, once again, willfully misinterpreted some piece of information.I notice you've changed the picture - the other one showed better the divisions of the different groups of foraminifera (remember that this is a phylum not a species), however I can still work with this new graph as it shows the major groupings of forams. There are ~13 known orders of foraminifera, with more taxon divisions below that. Parker and Arnold said that they had documented over 300 species ("Counting both living and extinct animals, about 330 species of planktonic forams have been classified so far, Arnold said."), so there are likely quite a number of extant species.Here is your previous image for reference (from your actual source):

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The Fossil Record

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Notice that the width of the bars in this graphic represent the number of families within each group, so we still are not down to the species level or even the genus level.BTW -- I'll echo Percy here: if you are going to post pictures or quote sections of articles you should provide links to your sources as part of your evidence, it's that old thing about proper credit where it is due eh?Here is the text that accompanies your current picture:

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Consider the following illustration and note that the foraminifers of today vary in morphology according to changes in ocean depth. As illustrated above, Tosk argues that morphologic variation or "sorting" within the geologic column can be based on normal ecologic distribution. Tosk goes on to argue that within a single foraminifer species, certain members may have thickly ornamented tests under normal oxygen concentrations and thin less-ornamented tests in environments where oxygen concentrations are low. Such variations that are based, not in genetics, but in environmental influences, are called "ecophenotypic" variations. Based on these ideas, Tosk theorizes about how the geologic foraminiferan data could be explained by a rapid catastrophic burial:

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Evidently Tosk is a creationist trying desperately to explain away the vast geological ages and massive data on foraminifera with a global flood and half vast imagination. You should use (a) more current resources and (b) more reliable resources. Let's continue:This latest picture shows 14 different examples of forams occupying different ecologies, and this may be where the known orders were when it was published (in 1988). Certainly we cannot assume that this picture represents species or genera or even families of forams, as too few are shown.The second reason I thought you were blowing smoke, was that I had not run across the term you gave in any previous reading on forams, and it was not mentioned in the article on forams in wikipedia (not that this is an authority, just a relatively current referential starting point).The third reason I thought you had it all wrong, was that the article you quoted (without source) contradicted what you said:

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The diversity and distribution of modern benthic foraminifera has been extensively studied in order to aid the paleoecological interpretation of their fossil record. Traditionally, foraminiferal species are identified based on morphological characters of their organic, agglutinated or calcareous tests. Recently, however, new molecular techniques based on analysis of DNA sequences have been introduced to study the genetic variation in foraminifera. Although the number of species for which DNA sequence data exist is still very limited, it appears that morphology-based studies largely underestimated foraminiferal diversity.(Pawlowski and Holzmann, 2007) Emphasis added.

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Percy found the link to the abstract you quoted from: And here is the whole abstract:

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Diversity and geographic distribution of benthic foraminifera: a molecular perspective
Jan Pawlowski1 and Maria Holzmann2
(1) Department of Zoology and Animal Biology, University of Geneva, Geneva, 1211, Switzerland
(2) Department of Palaeontology, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria
Received: 19 March 2007 Accepted: 22 June 2007 Published online: 16 October 2007

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Abstract The diversity and distribution of modern benthic foraminifera has been extensively studied in order to aid the paleoecological interpretation of their fossil record. Traditionally, foraminiferal species are identified based on morphological characters of their organic, agglutinated or calcareous tests. Recently, however, new molecular techniques based on analysis of DNA sequences have been introduced to study the genetic variation in foraminifera. Although the number of species for which DNA sequence data exist is still very limited, it appears that morphology-based studies largely underestimated foraminiferal diversity. Here, we present two examples of the use of DNA sequences to examine the diversity of benthic foraminifera. The first case deals with molecular and morphological variations in the well-known and common calcareous genus Ammonia. The second case presents molecular diversity in the poorly documented group of monothalamous (single-chambered) foraminifera. Both examples perfectly illustrate high cryptic diversity revealed in almost all molecular studies. Molecular results also confirm that the majority of foraminiferal species have a restricted geographic distribution and that globally distributed species are rare. This is in opposition to the theory that biogeography has no impact on the diversity of small-sized eukaryotes. At least in the case of foraminifera, size does not seem to have a main impact on dispersal capacities. However, the factors responsible for the dispersal of foraminiferal species and the extension of their geographic ranges remain largely unknown.

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There are a couple of things to note here:

1. Ammonia is a genus, still not a species (one we will come back to later),
2. the second group is poorly documented due to the morphological similarities (especially with them all being single chambered), still not a single species,
3. both show "high cryptic diversity",
4. morphology-based studies (eg Parker and Arnold) largely underestimated foraminiferal diversity, and finally
5. the molecular DNA studies are new as of 2007 (rather than 1988).

Now, in general, when biologists talk about variations within a species they use the term variety. Several different varieties can exist within a single species, and it is common in many species to have distinctive varieties. To have ecophenotypic variants you would need to have distinctly different varieties within a genetic species.Conversely, when biologists generally talk about differences between species they talk about diversity, when speciation occurs the parent population diversifies into two distinct species.Cryptic means that different species look alike:Species complex - Wikipedia

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In biology, a cryptic species complex is a group of species which satisfy the biological definition of species; that is, they are reproductively isolated from each other, but their morphology is very similar (in some cases virtually identical).

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They are typically very close relatives and in many cases cannot be easily distinguished by molecular phylogenetic studies either:

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... italics for emphasis.So when the paper says that both examples "perfectly illustrate high cryptic diversity revealed in almost all molecular studies" they specifically mean that there are cryptic species that look very similar but that they are genetically distinct.They may be (likely are) closely related (especially given that Ammonia is a genus), but they are not variations within a single species.Likewise when they say that "morphology-based studies largely underestimated foraminiferal diversity" they means that there are more species than is readily apparent from just looking at the morphology due to the cryptic species looking so similar. Entirely the opposite of what your creationist website tries to pretend.Now I though I made this point clear when I posted the quote from the wikipedia article on forams (that mentions morphospecies but does not mention ecophenotypes): Notice that when we talk about modern planktonic forams, that there are some 40 morphospecies, 40 groups that are morphologically different.Now I though I drove this point home in the next post when I provided you with a second reference, this one on planktonic foraminifera, similar to the ones studied by Parker and Arnold, that ALSO talked about morphospecies: Notice that all the references to classification of forams as "ecophenotypic variants" are dated 1976 or earlier. Before Parker and Arnold (so they would be aware of this possibility) and before DNA sequencing for genetic analysis.Notice that this paper shows that what appeared to be "ecophenotypic variants" is now, by genetic analysis, seen as the genetic variation within the different morphospecies explained by the different genetic types, species classifications based on DNA instead.Now we come to your recent post. First, you will note that I did not introduce morphospecies, I provided the evidence from scientific studies of actual forams by scientists who classified them as morphospecies, and went on to show that the articles were indeed talking about morphospecies and not ecophenotypes. These articles show that you had it backwards. And again, you provide no reference of actual science done on forams to substantiate this claim.Please note that nowhere in my post did I mention "cryptic genetic variation" -- that this is YOUR misrepresentation of the argument against you. I mentioned cryptic species (because the articles talk about cryptic species), and I mentioned cryptic genetic diversity (reference above to terminology). So I went looking for scientific articles on forams and ecophenotypes to see what I could find.

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Just a moment...
DOI: 10.1306/A1ADD99E-0DFE-11D7-8641000102C1865D
GCAGS Transactions
Volume 28 (1978)

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ABSTRACT

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The shallow, brackish-water environment of San Antonio Bay, Texas, supports a benthic foraminiferal fauna whose major constituents are widespread around the margin of the Gulf of Mexico, the southern Atlantic Coast of the U. S., the West Indies, and in low latitudes along the Atlantic and Pacific Coasts of South America. Several species of Ammotium, Ammonia, and Elphidium have been recognized by most authors as the dominant taxa in these estuaries. A scanning electron microscope (SEM) analysis of the exterior test morphology in five species from San Antonio Bay (Ammonia parkinsoniana, Elphidium gunteri, E. galvestonense, Palmerinella palmerae, and Ammotium salsum) reveals that two distinct phenotypes are present within each species. Each phenotype of a given pair is linked to the other by transitional phenotypes whose taxobases vary clinally. The distribution of each member of a phenotypic pair is directly correlated with the distribution of salinity and temperature in the bay. Thus, the paired phenotypes are ecophenotypes. Smaller, thinly calcified ecophenotypes having fewer chambers characterize environments that are near optimum for the respective calcareous species; the agglutinant species A. salsum is small, thin, and made of fine grains, in near optimum environments. Larger, thickly calcified ecophenotypes having more numerous chambers are characteristic of environments that approach minimum tolerances of each calcareous species; A. salsum becomes larger, more inflated, and composed of larger grains in near-minimum environments. Field and laboratory evidence demonstrates that this paired ecophenotypy is caused by contrasting results of delayed reproductive maturation in minimum environments, versus accelerated maturation in optimum environments. Longer growth periods produce larger, thickly calcified tests; shorter growth periods produce smaller, thinly calcified tests. The phenomenon of paired ecophenotypy, though rarely mentioned, has persisted in low-latitude estuaries since at least the early Miocene, as demonstrated by a review of published records. Recognition of this characteristic among the cited and other species (living and fossil) will clarify much of the taxonomic and ecologic confusion that has arisen from close morphologic similarity among estuarine and near-shore marine phenotypes. It also will help to provide more accurate paleoecological interpretation and correlation of marginal marine strata.

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"Failure to take into consideration the particular characteristics of a group and the nature and degree of its variation may result in the artificial separation of many 'morphological' species on the basis of minor phenotypic variations, even when the population at a given locality or stratigraphic level contains the complete series of gradations between two or more of these. As these individuals represent minor portions of a continuous population, regardless of the method of reproduction, they represent a single biological species, for which subdivision is unwarranted."

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(Helen Tappan, 1976, P. 304)

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Note (1) that this is 1978, and (2) that these forams involved ("Ammotium, Ammonia, and Elphidium") are three benthic genera, one of which Ammonia is specifically referred to in the article on benthic forams that showed cryptic genetic diversity instead of ecophenotypic variation.New information displaces old mistakes.

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Geology; March 1986; v. 14; no. 3; p. 218-220; DOI: 10.1130/0091-7613(1986)142.0.CO;2
1986 Geological Society of America
Late Miocene shore in northern Costa Rica: Benthic foraminiferal record
Barun K. Sen Gupta1, Luis R. Malavassi2 and Enrique Malavassi3

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1 Department of Geology, Louisiana State University, Baton Rouge, Louisiana 70803
2 Refinadora Costarricense de Petroleo S.A. (RECOPE), San Jos, Costa Rica
3 Departamento de Quimica, Universidad de Costa Rica, San Jos, Costa Rica

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In northern Costa Rica, the upper part of a volcaniclastic lithostratigraphic unit (Venado Formation) contains low-diversity benthic foraminiferal assemblages. The geologic age of these sediments is interpreted to be late Tortonian—Messinian (N17), on the basis of the 6.1 0.6 Ma K-Ar age of a younger trachyandesite and an ostracode index genus from an older unit. The benthic foraminifera, in particular two ecophenotypes of Ammonia parkinsoniana (d'Orbigny), indicate that in the late Miocene, a shallow, brackish bay existed there, the shore lying to the north and west. The bay was an extension of the Caribbean Sea, already separated from the Pacific in this part of Costa Rica.

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1986 - still old stuff, and ... Ammonia again.The other articles I found mentioned ecophenotypes because they cited the old papers as part of the history of classifying forams. One of these papers is the one I've provided in Message 36.By the time that Parker and Arnold made their morphological analysis of all the known marine planktonic forams, the idea of ecophenotypes had pretty much disappeared, and when you get to all the current articles that are based on genetic analysis we see that previous classification involving "ecophenotypic variants" were eroneous, and that the slight morphological differences were due to real genetic differences between cryptic species. No, Kaichos Man, it is not always possible to tell when you just look at the morphologies, however when you use genetic analysis and determine that there are distinct different genotypes involved you can tell, due to real genetic differences between cryptic species.This is what science has done since 1988. It has invalidated your premise that ecophenotypes are rampant through the phylum, and it has consistently shown that there are more genetic species instead -- more diversity, not less. Parker and Arnold showed what a robust morphological analysis could do to the biogeology of forams, but they underestimated the diversity of species involved.As such their morphological tree of descent from common ancestors stands, not dismembered, but stronger as it is validated by the genetic analysis of planktonic forams. The transitions and speciation events they show are still valid transitional fossils, although they may represent genera instead of species.Enjoy.ps -- thanks with providing me with another creationist hoax site (for Message 56):
The Emperor Has No Clothes - Naturalism and The Theory of Evolution
telling lies to gullible believersEdited by RAZD, : linkEdited by RAZD, : clrty

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Note (1) that this is 1978, and (2) that these forams involved ("Ammotium, Ammonia, and Elphidium") are three benthic genera, one of which Ammonia is specifically referred to in the article on benthic forams that showed cryptic genetic diversity instead of ecophenotypic variation.

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New information displaces old mistakes.

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You are suggesting then, RAZD, that ecophenotypic variation doesn't occur in foraminifera?

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"Often a cold shudder has run through me, and I have asked myself whether I may have not devoted myself to a fantasy." Charles Darwin

ok, about those pictures with the sugar glider and the flying squirrel. i have a question: what did the prehistoric sugar gliders look like? where are the transitional fossils between where they didn't have extra skin, to the ones where the started to develop it, to the present picture? show me.

Well Kaichos Man, what do you think? The evidence shows that whenever genetic analysis is done, that no evidence for ecophenotypic variation is found, and in it's place, several cryptic species are found that are more than adequate to explain the previous old (1976) idea that ecophenotypic variation was involved.The evidence shows that the text accompanying your second picture, the one by creationist Trosk, is false, and that the different orders of forams are not all one species. His diagram is obviously a depiction of many of the same shells as the first diagram, which represents the orders of forams, not species, and when species are genetically distinct within the genus level, any attempt to claim that orders are one species is just plain ridiculous. Trosk is a discredited charlatan, and "Sean D. Pitman M.D." is either a gullible fool, delusional, ignorant of reality, or intentionally lying (your choice). You have the opportunity to learn from his mistake.Enjoy.

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Hi again hawkes nightmare, finding your way around? You mean the example of convergent evolution that was given in Message 14: If you reply to the message with the information you are replying to with the message reply button (there's one at the bottom right of each message):

... your message is linked to the one you are replying to (adds clarity). This helps people track back to see what the previous post was about.You can also look at the way a post is formatted with the "peek" button next to it. Why?You will note that these cute little guys are not presented as intermediate fossils, but rather part of a secondary test of evolutionary theory.The fact is that skin rarely fossilizes, and so such features are hard to distinguish in the fossil record -- they may be there but not noticed as ancestral to the sugar glider or flying squirrel.What we do know from the skeletal and genetic evidence of both animals, is that they have distinctively different features and traits under the skin, and that the appearance of similarity is just that: superficial skin deep appearance. The appearance of similar design would argue that similar DNA would be involved for the development of each, but this is not the case.This is an opportunity, however, to introduce another transitional fossil:

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Earliest bat fossil reveals transition to flight | Ars Technica
As you can see at right, the fossil is astonishingly well preserved. It comes from deposits that date to about 52.5 million years ago, a time when many mammalian groups were expanding, ... The species has been named Onychonycteris finneyi, meaning "clawed bat" and honoring its discoverer, Bonnie Finney. The clawed bat part refers to one of the many intermediate features that make Onychonycteris the most primitive bat species ever described. In all current and prior fossil species of bats, most of the digits in the wing lack the claws typical of mammalian digits. That's not the case here: all Onychonycteris digits end in claws. The hind limbs are also unusually long, as is the tail, but the limb contains a feature that suggests the presence of a skin flap between the hind limbs and the body.

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The relatively short wings and long hindlimbs place Onychonycteris outside of all previous bat species in terms of the ratio between its limbs. In fact, a plot of this ratio puts the fossil species neatly between bats and long-armed creatures like slothsexactly what would be expected from a species at the base of the bat lineage. The authors argue that the configuration of its limbs, combined with the claws, suggests that it would be powerful climber, able to easily scramble around trees when not flying.

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Note that there is no fossil evidence of the skin, so the attachment of the skin to the skeleton is inferred from secondary evidence. This is the abstract link for the Nature article (you will need sign in privilege to read the full text):

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Primitive Early Eocene bat from Wyoming and the evolution of flight and echolocation | Nature
Here we describe a new bat from the Early Eocene Green River Formation of Wyoming, USA, with features that are more primitive than seen in any previously known bat. The evolutionary pathways that led to flapping flight and echolocation in bats have been in dispute7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, and until now fossils have been of limited use in documenting transitions involved in this marked change in lifestyle. Phylogenetically informed comparisons of the new taxon with other bats and non-flying mammals reveal that critical morphological and functional changes evolved incrementally. Forelimb anatomy indicates that the new bat was capable of powered flight like other Eocene bats, but ear morphology suggests that it lacked their echolocation abilities, supporting a 'flight first' hypothesis for chiropteran evolution. The shape of the wings suggests that an undulating gliding—fluttering flight style may be primitive for bats, and the presence of a long calcar indicates that a broad tail membrane evolved early in Chiroptera, probably functioning as an additional airfoil rather than as a prey-capture device. Limb proportions and retention of claws on all digits indicate that the new bat may have been an agile climber that employed quadrupedal locomotion and under-branch hanging behaviour.

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Here is the graphic showing the plot of limb ratios from the full article in Nature: You will notice that Onychonycteris finneyi is exactly between the non-flying cohorts and the flying bats known in the fossil record and modern day.Note that Symphalangus, the blue triangle closest to this fossil, is a gibbon. Bradypodidae, the next closest, are sloths, Sciuridae, near the bottom left, are squirrels, and this would include the flying squirrel. Scandentia are tree shrews, thought by many to share a common ancestor with bats. Cynocephalus is a "flying" lemur: A transitional fossil is one that shows traits intermediate between ancestral forms and descendant forms, and this bat is clearly between modern bats and non-flying arboreal organisms.Enjoy. Edited by RAZD, : addd

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nice with the bat. very well presented evidence, but i believe it was just a type of bat that died out because it couldn't adapt o its environment, not a transitional species. and as you should well know, different species cannot interbreed, so you cannot say that another ype of bat got it on with this one.thank you for your concern with my being new here, but i know the layout of forums, as i am currently registered to about 5 or 6 of them. you will see me as hawkes nightmare on all of them.