Are human tails an example of macroevolution?

Thanks for the honesty Equinox.I did not even have any idea that you even tried to read my posts. I do not think we have ever had any exchange of comments on EVC.As for me using a simple link to creationist literature this time, well, that is all that was called for.But look, I can get very very clear and clean if and when the argument that I making hay in gets to that place. Because it is rare for someone to make it to a third repeition with me is part of the reason the issue stays as I have said once before, "muddy."In this case did you see how Bernd's question actually gives rise to TWO MORE biologically?If not let's get really clear and clean,Is there any evidence that human tail morphology has a functional purpose for the human lineage? THAT is what is at issue.Look at a snake and notice that some pythons have "legs" or spurs rather. Does this mean by this anatomy that a snakes legs are just anomalous growths or do they have some function that might be selected for and result in populationally variant allele fluctuations for its existence? Well, snakes DO use thier "spurs" during courtship, so it is possible that their legs are not like a human tail as Gish suspected as being caused by deviant embryogeny but instead are mutations that who knows, might cause snakes to HAVE longer legs in the future.I, personally, do not have any evidence about human tails, but given Gish's response I would doubt there is any indication that human tails result in differential human reproductive success (prevention of anal sex etc.).If Bernd wants to draw the conclusion that tails are a problem for creationsists BECAUSE admitting a functional use entails common anscetry with MONKEYS (which unlike apes really DO use their tails a lot) then he has to first show that human offspring with some freqency selectively and activley exhibit such and so survive elseI see NO WAY to deny Gish his response , ESPECIALLY given the current evo atmosphere of developmental constrainsts and evo-devo. This is not the same issue necessarily as of human vs chimp DNA.When I asked Bernd for the implication, I was asking HIM for what IN ANY PROCESS OF THOUGHT OF EVOLUTIOANARY THEORY enabled him to infer that there was a benefical mutation IN THE ^HUMAN^ TAIL. There is clearly a benefit for monkeys but where is the beneficiary extant among Homo sapiens? I would suspect like being diagnosed, having a tail is likely a social detriment rather than a benefit.There is no bad blood between you and me so you do not need to apologize to others. As for me, well, in this case I may need to give you personally some more informaton about ideas of "constraint" so that there is no "slogging." Just try to respond to this ONE POST. I'll do my best to clean it up and make it even clearer if that is needed.Edited by Brad McFall, : ? markEdited by Brad McFall, : small wordsEdited by Brad McFall, : word "to"

A similar argument has been made for cetaceans with "legs" that leaves me undesired. Those are anchor points similar to a snakes spurs that aid in copulation. This, to me, is just another case of percieved lineage that relies on circumstantial evidence to present its case. Certain scientists may be inclined to claim that they are atavistic legs when in reality all it is an anchoring mechanism to aid in sex.If these "tails" really are vestigial, why would this phenomenon of turning on specific loci present itself more regularly in, say, Chimps or Apes? According to most pro-evolutionary anthropologists, chimps and apes are more closely related to a Rhesus Macaque, so why wouldn't these atavistic traits present themselves in more related species? Is it because its not a tail at all but rather a deformity?

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"There is not in all America a more dangerous trait than the deification of mere smartness unaccompanied by any sense of moral responsibility." -Theodore Roosevelt

Or that "may" not be how scientists do science. Could you provide us with more than self-serving speculation? No.Where on earth did you get this strange, strange idea?No anthropologist would tell you that. Not one.---Before you start going around telling people what scientists think and why they think it, do you not suppose that you have some sort of obligation to find out what they do, in fact, think, and the reasons why they do, in fact, think it?Edited by Dr Adequate, : No reason given.

NJ, I'd like to remind you to read carefully posts made in reply to you.It is polite and shows some intellectual honesty to respond when you are corrected about some misapprenhension of fact that you have shown.Failure to discuss in a polite and honest fashion will result in short suspensions. (A lot of them).

Okay, what did I say that intellectually dishonest and where was I impolite to the point where you feel warranted in threatening me with suspensions...... (lots of them)?

Proactive only. Just be sure to behave.Edited by AdminNosy, : correct the author

NJ writes: Names, credentials, and positions please.

Hello Brad,in your presentation of a creationist position you quoted Gish with: This position is falsified by the three cases with vertebrae presented in my opening post Gish discusses an example of an pseudo-tail, not of a real human tail, therefore his argument is irrelevant. For a description of a real human tail please read Human tails and pseudotailsThere are documented cases that real human tails have been inherited (in one case over three generations of females)
See: Standfast, A. L. (1992) "The human tail." New York State Journal of Medicine. 92: 116You quote Gish with indicating that he may accept this as a possibilty. From the context it’s obvious, that he doesn’t consider this seriously. Besides that, admitting that a distant ancestor of homo sapiens had a tail is tantamount to admitting macroevolution.Finally you ask: No, there is no evidence that the human tail is the result of “a complex mutational existence”. On the contrary it’s probably due to a mutation of a regulatory gene which controls the apoptosis of the tail in embryonic development. The problem for the creationist position is:
Either admitting that homo sapiens has a working pathway to develop a tail which simply is repressed (and in the cases we are discussing unrepressed) - that would be evidence for an distant ancestor with a tail - or accepting the occurrence of mutations which construct de novo a tail with nerves, muscles, connective tissue and in some cases vertebrae.-BerndEdited by bernd, : TypoEdited by bernd, : typo

Hello nemesis_yuggernaut,just to remember the topic of the opening post, we discuss how creationists explain true human tails. I would propose that we deal step for step with your post. In the first sentence you claim: Here are two article which contradict your claim:The abstract of
Human tails and pseudotails reads: In the abstract of The human tail: a benign stigma. Case report. we get some more infomation: So, can we agree that there are indeed documented cases of true human tails?-Bernd

Hello Brad, No, that’s not the issue. When the human tail is not a atavistic structure, as creationists claim, how do they explain the development of this complex trait more than 33 times in this century?When on the other hand there is an existing pathway to develop a tail in humans which merely is repressed, how is this not evidence for a distant ancestor with a tail?Besides, I admit that creationist don’t have to assume that human tails are beneficial, there is most probably no evidence for that (My formulation in the opening post was badly worded, I should have written: mutations which give rise to new functions)
On the other hand when mutations frequently create complex structure like the human tail doesn’t this provides more than enough traits selection can work on? So given that the rate of beneficial mutation is somehow dependant on the mutational input, wouldn’t we conclude that this rate will raise too?-BerndEdited by bernd, : deleted the word "heritable" in second paragraph, see message 27 from Wonded King, Edited by bernd, : correction: replaced vestigal organ with atavistic structure in first paragraph

see this is were you are not really understanding evolution, the organs lost most of their use as legs and were co-opt as anchers for reproduction, since this is also a secondary fuction of legs as well.
ever seen animals on animal planet they use thier legs to hold on to the females
plus in snakes they sometimes do no reabsorb the legs so some snakes are born with them developed, which is how we know they had legs

Given that the source you cite states that such tails are rarely familial can you really claim that this has arisen as a heritable trait in more than 33 instances?TTFN,WK

Hello Wounded King,thanks for the hint. I will correct this.-Bernd

I will answer

quote:

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When on the other hand there is an existing pathway to develop a tail in humans which merely is repressed, how is this not evidence for a distant ancestor with a tail?

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very directly by attaching a response to your other post to me after I read your link(s). It may take me through weekend because I want to clear up some readings I have been making of Gould, a little farther. I will not skip the question immediately above in this thread but WK already said what was necessary(heritbility vs nonheritability)(A developmental constrait causing phenotypic expression clinematically is deviant and not necessarily heritable (in general)). I will show how a latent genetic affect can effect non-heritable expression (neophenogenesis is a case study) in general, but I will also look for some evidence that human tail expression may not be developmental deviation from Waddington's canalization as understndable in post-neoDarwinism.And if this is stuff you already understand... the existence of a "tail" for a human or a "leg" for a snake may imply non-existence of such a phenetic in an ancestor of such a grade if the PLAN or Bauplan implies THROUGH THE CONSTRAINT certain boundary conditions on form-making that sequester placement in "morphospace" proactively (having to do with whether the Waddington canalization is widened or narrowed). My sense of these spatial relations is not as good for mammals as it is for reptiles and amphibians where deviation from the central midline is easier to "interpret."You seem to be starting from the thought that creationists have the idea FIRST that the tail is a vestigial organ for humans. I have tried to present a different path of possible creationist thought.When I first started posting on the ICR web forum, before I was posting here, I noticed there was a tendency to speak about "vestigiality" a bit much. If ICR still has its discussion forum cached it might be possible to see how I dealt with this issue post by post, but I have not seen the Forum since then (about 1998).If your issue REALLY has to start with a "vestigial organ" then the ANSWER has to do with the notion of "WILD TYPE." Is this the direction you are going (or wait till I post a second time to see an alternative).Edited by Brad McFall, : spelling

I will try to slug through but it is going to be a very short trip for really a much longer needing replies.The short is that when thinking about snakes one ends up with a thought about oxygen in fish BEFORE one considers the issues of warmbloodedness and ape vs monkey behavior when beyond birds and or dinosaurs. At least that is how it works for me. Thus BEFORE I think about whales by any analogy I have to deal with gills in salamander larvae. Some day I will give the warmbloods more than a ramet of a chance. Sorry that IS my peculiar BSM response. This is what Equinox thought might have something in it. It does. I will strech THAT out further.When thinking about snakes and legs one is actually trying to think about classification of SQUAMATES (lizards and snakes (and I dont suspect you will say that lizards do not have legs in the same sense you ask if humans have tails or not))at least. The point I was making was in trying to distinguish "complex genetic mutation" hence 'legs' IF LEGS were selected and inherited in a past (commonality of lizards and snakes)(thus the evolutionist who thinks from fins to legs to warmbloodedness is likely to START here) from developmental deviation or side-consequence of some other acquired (not necessarily Lamarckian)character LATERALIZATION of SWIMMING MOTION (issue of how man digits fossil fish had). Thus human might have tails and have not legs as weird as it sounds. I have doubted this is the case and am trying to see where the evidence is that a human "tail" is something other than a NON-bilaterally symmetric trait. If all the evidence of tail morphology in humans is radially symmetic or nearly so to any concept of possible adaptiveness I will be justified in holding that the tail man IS UNLIKE (grammatically)the leg of squamate (even though there is osteological phenetic similarities). The existence of BONE without ennervation seems to speak in favor of my current opinion IN THIS THREAD or filament.If the bone has processes that can likened to monkey functional tails I will alter my suspicion but till then... the LEGS of snakes or whales HAVE TWO SIDES, on the left and on the right. Again, I have not thought much about whales so back to snakes.The spur you might think or say has just as little morphological variety as a human tail as we have seen presented on EVC but did you also know that in addition to a forked tongue the snake has HEMIpenii
SPLIT down the middle and the male snake will ALTERNATE which side it copulates on? This induces a Behavorial component to the mophology that I have doubted is in existence for the human dermal growth s0-called by Gish. It may be that the correct scope of anantomy needed to a proper discussion of the snake LEG involves also the PENIS. I do not know. But THAT opens up a whole large area when one starts to uncover the reproductive behavior of both males and female squamates. I do not know that the spur is an "anchoring" mechanism. Have you seen this so described or is that your idea??It could be that the spur is used to change the position of the female so that the male can alter which side "HE" is moving into. I just have not read enough of this literature to know. As far as if the structure itself is only for use "in sex" and nothing but "circumstantial evidence" you should understand that much of the differences in the higher level classification of lizards and snakes relies on the relation of the vertebra via the muscles to the skin but with the existence of spurs this changes THAT homogneous perspective definatively thus it seems to indicate relation OUTSIDE the lizards and snakes rather than sexually inside it (unless one was to relate clades to sex dimorphism (I have not seen such a paper)).