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Author Topic:   If evolution is true, where did flying creatures come from?
RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 57 of 225 (757346)
05-07-2015 4:06 PM
Reply to: Message 56 by Zatara
05-07-2015 9:59 AM


Re: Evolution of Birds -- another old bird
Welcome to the fray Zatara,
Though there is disagreement among biologists, most agree birds evolved from dinosaurs. Archaeopteryx is the first good example of a "feathered dinosaur." It was discovered in 1861 ...
We actually have a number of fossils besides Archy, and a new one has just been found in China:
The oldest record of ornithuromorpha from the early cretaceous of China (Nature Communications, Article number: 6987 doi:10.1038/ncomms7987 Published 05 May 2015)
quote:
Ornithuromorpha is the most inclusive clade containing extant birds but not the Mesozoic Enantiornithes. The early evolutionary history of this avian clade has been advanced with recent discoveries from Cretaceous deposits, indicating that Ornithuromorpha and Enantiornithes are the two major avian groups in Mesozoic. Here we report on a new ornithuromorph bird, Archaeornithura meemannae gen. et sp. nov., from the second oldest avian-bearing deposits (130.7 Ma) in the world. The new taxon is referable to the Hongshanornithidae and constitutes the oldest record of the Ornithuromorpha. However, A. meemannae shows few primitive features relative to younger hongshanornithids and is deeply nested within the Hongshanornithidae, suggesting that this clade is already well established.
Figure 1: Holotype of Archaeornithura meemannae gen. et sp. nov., STM7-145.
Holotype of Archaeornithura meemannae gen. et sp. nov., STM7-145.
(a) Main slab; (b) counter slab. Anatomical abbreviations: al, alular digit; ba, basicranium;
co, coracoid; cv, cervical vertebrae; d I—IV, pedal digit I—IV; fe, femur; fi, fibula; fu, furcula;
hu, humerus; ma, major digit; mi, minor di
Ornithuromorpha is the clade of birds that all living birds but not Enantiornithes nest in refs 1, 2. Until now the earliest record of this group was from the lower Cretaceous Yixian Formation (125 Ma), ... Therefore, the Huajiying Formation is the second oldest avian-bearing deposit in the world, only after the Upper Jurassic Solnhofen Limestones that preserve Archaeopteryx in Germany ...
Lots of good stuff in the article, including images of the fossils of the feathers.
Enjoy
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RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(2)
Message 71 of 225 (757410)
05-08-2015 12:24 PM
Reply to: Message 59 by Faith
05-07-2015 11:48 PM


Re: Evolution of Birds
Hi Faith, back at it again eh?
But what's so odd really, is that very noticeable changes occur within a few generations when you isolate a small number of a Species. Darwin demonstrated this with pigeons, getting extreme variations in a very short period of time just by breeding to enhance a chosen trait. ...
Indeed, what you had was the joint effect of mutations and selection. His insight was that the selection process occurred naturally, where animals that survived and bred passed their genes (that enabled them to survive and be selected by mates for breeding) to the next generation.
The ability to hop a little further because of the arrangement of feathers enabled the bearer more survival ability to catch or evade. Feathers could also be a means to attract mates as we see today, so selection for greater feathers by sexual selection led to the proliferation of feathers that then became an asset to hop and glide and finally to fly.
... All this demonstrates is the great variability that is built in to a Species, ...
In know this is your pet theory, and you have presented it hundreds of time, and every time it gets refuted by evidence that shows new DNA in species that did not have it before.
What is built in is a predilection for mutation that provides the variation that selection works on.
... that develops through microevolution if the breeding pool is isolated. Isolation can occur either artificially by human manipulation, or by natural factors such as migration of a small number of a Species in the wild. Either method will produce a new type or breed or race or variety.
Correct -- isolation leads to different selection pressures on the different populations, as has been discussed with black pocket mice in the southwest. The same for the Peppered Moths -- different environment produces different selection processes that result in visible changes.
Change is built into the genome, ...
Change is built into the susceptibility of DNA to mutate, during the creation of sex gametes or during the process of cell division during the development of an organism. The development can be affected by chemicals, hormones and temperature. An example of the is the Russian silver fox experiment where the foxes were selected for less aggressive behavior over several generations, and the offspring evolved to be more like dogs, with floppy ears, spots, and behavior changes relative to the parent population.
... but it can only vary the traits of the particular Species that are programmed into its genome, it can never produce something that is not already genetically available to that Species.
This statement has been shown to be false time and again. That you keep repeating this fallacy does not begin to make it valid. Several bacteria studies show the appearance of DNA sequences that did not exist in the study population at the start.
... Oodles of time isn't going to make one Species into another ...
If you mean turn a cat into a dog, then of course that isn't going to happen -- but that is not how (macro)evolution works, so that not happening just disproves a fallacy.
If you mean that new species are not going to rise out of varieties and continued microevolutionary process in isolated populations, then you are wrong because the development of new species has been observed.
... This is macroevolution's ultimate downfall. ...
Except that it isn't macroevolution, but creationist pseudomacroevolution that fails.
Macroevolution in evolutionary biology is the process of speciation and the formation of nested hierarchies. You already understand the basic mechanics of this:
... Either method will produce a new type or breed or race or variety.
... which is the beginning of speciation (new species formation)and the formation of nested hierarchies. We see this process taken to the next level with the Asian greenish warblers (Phylloscopus trochiloides):
... where P.t.viridanus (blue) is almost completely isolated, but shares a small overlap interbreeding zone with P.t.ludlowi (green), which is almost completely isolated, but that also shares a small overlap interbreeding zone with P.t.troichilodes (yellow),which is almost completely isolated, but that also shares a small overlap interbreeding zone with P.t.obscuratus (orange),which is almost completely isolated, but that also shared a small overlap interbreeding zone with P.t.plumbeitarsus (red), but now we get to the interesting part ... P.t.viridanus (blue) and P.t.plumbeitarsus (red) share a small overlap zone but do not interbreed -- they are reproductively isolated, so variations in one population are not shared with the other population.
This is how speciation -- the development of new species -- occurs, but normally the process happens over time instead of over distance.
... If the Species is genetically equipped for fur it isn't going to grow feathers no matter how clever you are at breeding strategies. ...
Well, I think we can agree that this has not happened and is not likely to happen.
But in my case, it would not be likely to happen because there would be no reason for it. What would be the selection pressure to change fur into feathers? Bats fly with fur instead of feathers, they took a different evolutionary path dictated by what they had available to be mutated and developed into wings. Bats don't need feathers to fly so there is no pressure for them to evolve.
Flying squirrels and sugar gliders and Colugos and Wallace's frogs and flying fish and flying geckos and flying boa snakes have all taken different evolutionary paths dictated by what they had available to be mutated and developed into winglike surfaces -- whether those wing shapes were good enough for powered flying, or more often just sufficient to glide.
Multitudes of insects have developed flight, some even evolve wings lose wings and then re-evolve wings. Insects don't need feathers to fly either, and would likely be encumbered if by some strange metamorphosis they did evolve feathers.
Macroevolution of species is not metamorphosis of individuals.
Small spiders fly by kiting a strand of web material, and drift with the wind in much the same way that multitudes of plant have flying seeds.
... OR, if you get something in the direction of feathers by assiduous selection, you will sacrifice so much else to the effort you may not even have a viable living creature at all in the end. That is, if you try to breed from an anomaly you will most often get disease and deformation. ...
Agreed, artificial selection can -- and has -- resulted in organisms that would be less fit in the wild than their parent populations. Many dog varieties fall into this category, many with endemic problems that plague them.
... That is, Species are capable of change but there are limits. ...
What are those limits? Where are those limits observed?
Or is it like flipping a coin ... each flip of a coin can be heads or tails, but what it was in the last generation of flipping has no effect on what will happen with the current flip.
... Extreme change, ...
What change is "extreme" Faith?
... even if produced by a series of small changes, ...
At what point does continued small change become "extreme" -- what is your measure of difference?
... is more likely to lead to extinction than further ability to change.
Each step in the process is an adaptation for better survival and reproduction in a changing world, and like the coin there is no reason for the future to be affected by the past, no chain that says "this far and no farther" that has ever been discovered.
In fact as species diversify and spread into more different ecosystems, adapt to those ecosystems and evolve into new species it is more likely that one will continue to survive than an unchanging population of the parent species. The fossil record is filled with species that lived and then were replaced by newer species.
... Thus dies the Theory of Evolution.
Alas, all that dies is your strawman caricature of the theory of evolution.
The Theory of Evolution (ToE), stated in simple terms, is that the process of anagenesis (linear or phyletic speciation), and the process of cladogenesis (divergent speciation and the formation of nested hierarchies), are sufficient to explain the diversity of life as we know it, from the fossil record, from the genetic record, from the historic record, and from everyday record of the life we observe in the world all around us.
These processes have been observed and that means the theory is supported by objective empirical facts. In addition, nothing has been observed that invalidates this theory, and certainly false and misleading arguments based on misunderstanding evolution do not invalidate the theory.
Fossils show what once lived, they do not necessarily show whether they were related to other fossil forms or not. ...
Curiously you are splitting of hairs of much less significance than you think.
First fossils are snapshots of individuals rather than of the whole breeding population. Second there are fossil records that show the amount of variation within one generation overlaps with the variation in following generations -- such that many individuals could be members of either population, and the only difference is the time of their appearance in the fossil record:
You can draw vertical lines from the ends of each layer of fossils and see that generation to generation they share the majority of overlapped variations, but that after several generations the then current population has variations that were not found in the original parent population: all P.jarrovii are different from all P.ralstoni ... before dividing into two independent daughter populations, N.nunienus and N.venticolis that don't overlap each other but each overlaps portions of the parent population.
These fossils are all found in the same habitat\location, separated only by time, and to ignore the morphological similarities to claim they are not related is more denial than objective consideration.
If the morphological change from generation to generation is less than the morphological variation within the populations -- the variation due to microevolution -- and if there is clear geological\ecological continuity, then it is reasonable to see they are just as related as are humans from one part of the world related to others in other parts of the world.
... The idea that birds evolved from dinosaurs is based only on some morphological similarities and position in the fossil record. ...
Actually it is based on a majority of morphological overlap of traits and on a continuity of geological\ecological just as is the case for the Pelycodus above.
And curiously this overlap of evidence continues to grow as more fossils are found, with more and more intermediates in forms rather than more segregations into distinct unrelated groups.
Dinosaurs evolved feathers before they developed flight -- the development of feathers enabled the development of flight from already existing traits in the parent populations.
... We can tell if a fossil was related to a currently living thing by its morphology, but it's sheer speculation to claim descent from one Species to another.
And I will agree that some speculation is involved in saying that species (X) evolved from species (Y), but I will disagree on the degree of speculation involved: the speculation is highly informed by the amount of morphological similarities, by the congruity of space and time, and by the intermediates between one population and the next, such that if species (X) did not evolve directly from species (Y) that it must have evolved from a close cousin species to (Y) -- one that could have been a small isolated subpopulation of a parent population to both it and species (Y).
Curiously, the theory of evolution does not depend of showing direct unambiguous descent of one species from another, just that the evolutionary processes that we know - and have observed - happen can explain the evolution of one from the other. Does the change in morphology fall with the range of morphological differences possible? Is there a distinct and clear lineage in time and location?
And I know you have seen all this before.
Enjoy

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This message is a reply to:
 Message 59 by Faith, posted 05-07-2015 11:48 PM Faith has replied

Replies to this message:
 Message 73 by Faith, posted 05-08-2015 4:42 PM RAZD has replied

  
RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


(1)
Message 204 of 225 (757706)
05-12-2015 10:44 AM
Reply to: Message 73 by Faith
05-08-2015 4:42 PM


Evolution produces new alleles - the evidence is there
Moved to Evolution Requires Reduction in Genetic Diversity Message 413 to keep this thread topic on evolution of flight
Edited by RAZD, : moved post to more appropriate thread
use peek to see or go to link above
Edited by RAZD, : sp in hidden text

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This message is a reply to:
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RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 205 of 225 (757716)
05-12-2015 12:19 PM
Reply to: Message 185 by Admin
05-12-2015 6:37 AM


Re: Moderator Clarification
Just caught up. Been a tad sick and so dosed up on meds and sleepy.
I see lots of ground covered since my previous post, and yes it is off topic: do you want me to move my post to the other thread?
Thanks

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This message is a reply to:
 Message 185 by Admin, posted 05-12-2015 6:37 AM Admin has replied

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RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 212 of 225 (757799)
05-14-2015 10:41 AM
Reply to: Message 210 by Denisova
05-13-2015 5:58 AM


Re: Moderator Clarification
Welcome to the fray Denisova, are you connected with denisovians discovery?
Is there also a way to move a post to another thread altogether, so not mere copying it but actually replacing?
See what I did in Message 204 and Evolution Requires Reduction in Genetic Diversity Message 413 -- you can hide the message when you edit it to copy for the reposting on the other thread, and then one can look (peek) at it if they don't want to go to the other thread.
Enjoy
ps -- when you |peek| a message the url line gives you f (forum) number, t (thread) number and m (message) number:
EvC Forum: Message Peek

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This message is a reply to:
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Replies to this message:
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RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 213 of 225 (757800)
05-14-2015 10:45 AM
Reply to: Message 208 by Faith
05-12-2015 5:55 PM


Hi Faith,
I overused my eyes yesterday, have a horrible eyestrain headache and have to be off the internet at least until tomorrow, hope not longer.... and I'll try to deal with the rest of RAZD's post.
I've had horrid headaches as well, hence my reduced posting ...
Please continue on Evolution Requires Reduction in Genetic Diversity and reply to Message 413 when you are able.
Enjoy

we are limited in our ability to understand
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This message is a reply to:
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RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 215 of 225 (757882)
05-15-2015 10:35 AM
Reply to: Message 214 by Denisova
05-15-2015 5:44 AM


back to the topic
No, that would be too much credits!
Ah well, you never know in a place like this. You realize by now that you are addicted yes?
Re: Moderator Clarification
So I ran across this and thought it would be good to discuss in relation to the topic:
Beijing to Boston: Chatting About Yi qi, Part 1 | National Center for Science Education
quote:
CS: Yi qi fits nicely among the Scansoriopterygidae, a somewhat enigmatic group of theropods close to the origin of birds. There are two other definite Jurassic scansoriopterygids, Epidendrosaurus and Epidexipteryx, and Zhongornis from the Cretaceous might be a third member of the group, so Yi qi is either number three or number four. All these animals, though, including Yi qi, are known from rather imperfect specimens, so some aspects of their anatomy are still unclear. However, we do know that scansoriopterygids are closely related to birdsthey’re either the closest relatives of birds among non-avian dinosaurs, or a couple of nodes further away from birds, depending on whose phylogenetic analysis you support.
A couple of months later, I was reading a lot of stuff about flying and gliding vertebrates for a totally unrelated project. I came across a passage in a textbook that said modern flying squirrels (which actually glide, of course) have a cartilaginous strut, which helps to support the membranous wing, extending from either the wrist or the elbow. At the mention of a strut extending from the wrist, my mind immediately jumped back to the strange little dinosaur I’d seen in Shandong. At first the analogy seemed very far-fetched, but as Xu Xing and I began looking into it more, we became convinced that it held some water. That was when Xu invited me to join the project.
Right rod-like bone (labelled) of the new dinosaur Yi qi,
with membranous tissue preserved around the tip of the
bone and filament-like feathers preserved elsewhere in
the image. (Credit: Mr. Zang Hailong)
What we found was two critical, essentially independent pieces of evidence for a membranous wing in Yi qi: the rod-like bone coming out of each wrist, and the patches Right rod-like bone (labelled) of the new dinosaur Yi qi, with membranous tissue preserved around the tip of the bone and filament-like feathers preserved elsewhere in the image. (Credit: Mr. Zang Hailong) of sheet-like soft tissue preserved alongside the rod-like bone and the fingers. Xu Xing spotted the patches of sheet-like tissue, which certainly lend themselves to interpretation as pieces of a flight membrane.
Beijing to Boston: Chatting About Yi qi, Part 2 | National Center for Science Education
quote:
SK: With this discovery, you’ve really added a new wrinkle to the whole how-did-flight-evolve questionwhich I’ve always found a little silly, actually. I remember when we Microraptor gui, subject of a 2003 Nature cover story. (Gelweo via Wikimedia Commons) were in graduate school, and in the same week in 2003, Nature’s cover story was about the newly discovered dinosaur group known as microraptors from China, with four wings that suggested gliding, while Science’s cover story was about Ken Dial’s study suggesting that flapping underdeveloped wings helped baby birds run up hills. So it was trees-down in Nature and ground-up in Science. I remember thinking, Why does it have to be one or the other? Doesn’t it make sense that both happened? Are you surprised to have found this new category of flying dinosaur? Do you think there are other variations out there waiting to be found?
CS: I certainly think it’s plausible that different theropod species close to the origin of birds could have been in the trees, on the ground, and everywhere in between, and found feathers and other incipient flight-related structures to be useful in all these contexts. After all, it’s not uncommon for closely related species in the modern world to vary in their ability and inclination to climb trees. So yes, I agree that the ground-up and trees-down accounts of the origin of flight aren’t necessarily mutually exclusive.
... But what is surprising about Yi qi is the sheer starkness of the difference between its membranous wing, supported by a rod-like bone, and the feather-based wings that are typically present in birds and their close relatives. The wing of Yi qi seems less like a new variation on the usual theme than like a whole new theme of its own, and in that sense it’s a very exciting discovery indeed.
Artist’s impression of Yi qi, illustrating one
possible wing structure, what the authors
call "the bat model." Image may be used
freely to accompany an article on the
discovery of Yi qi (Credit: Dinostar Co. Ltd)
sK: ... What do we know about Yi’s flight abilities?
CS: Well, we don’t know the shape or size of the membranous wing, or even the form of the tail (which could have an important impact on the animal’s aerodynamics), which makes it difficult to say very much about how Yi qi moved through the air. One argument we do make in the paper, although it’s not backed up by any kind of quantitative analysis, is that flapping flight requires rapid, fairly elaborate forelimb movements, whereas the rod-like bone coming out of the wrist must have been a fairly unwieldy structure. With that in mind, I suspect that Yi qi was mostly a glider, though it might have combined gliding with some awkward flapping. Gliders pretty well have to start from some kind of elevated perch, so I guess that implies trees down rather than ground up for Yi at least.
It's obviously a dragon
Enjoy

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This message is a reply to:
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RAZD
Member (Idle past 1486 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 225 of 225 (758789)
06-02-2015 3:14 PM
Reply to: Message 217 by Belcher
05-26-2015 2:07 AM


Questions
Hi Belcher, and welcome to the fray.
Agreed with you on this point that science can answer many of question but still the science could not justify the death rate and birth rate, the milk phenomenon and many other things you might get the confusing answers from science ...
Curiously I am not confused by what is not yet known but excited: science approximates reality by testing explanations against objective empirical evidence, if the explanation fails we toss it and try something else. This way the approximations constantly increase in accuracy.
... but you will get firm answers from a true faith. Hope you got the answer.
Question 1: how do you test\know the "firm answer" for accuracy?
Question 2: how do you test\know which faith provides the best answer?
It is fine to be skeptical of science, but you should equally be skeptical of faith, yes?
btw -- if you are interested, we can find a better thread for your questions\answers, as the topic here is specifically about where flying creatures came from: keeping topics focussed helps everyone follow the thread.
Enjoy
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