Evolution Logic

well, what we have is the proof that one gene alters a condition which must previously exist. birds had feathers on all four limbs prior to developing scutes. in fact, we see confirmation of this in the fossil record: we have some nice four-winged dinosaurs.but your post makes an additional error. while scutes and feathers are very similar in composition, scutes/feathers and reptilian scales (such as the ones found on the bottom of a bird's foot) are not the same at all. feathers evolved from something else. all of the earliest feathers we have are more similar to hair than to scales.Edited by arachnophilia, : typod

---

we have quite a lot of examples with stuff similar to down. we even have a tyrannosaurid (dilong paradoxus) now that has downy feathers.added by edit: kind of a funny term. birds ARE dinosaurs. so you can have bird-like dinosaurs, but not dinosaur-like birds. more primitive, yes. more similar to non-avian dinosaurs, yes.Edited by arachnophilia, : No reason given.

---

no. not at all. for starters, not all reptiles have scales in the manner that you are probably thinking. quite a lot are rather smooth skinned. and, we have a number reptiles, and things descended from sauropsids, that have hair. while early mammals/thecodonts are not the best example, pterosaurs are much more closely related. they are also archosaurs, reptiles, and many have hair.feathers are hair-like structures, and simplest feathers (like down) are nearly analogous to hair in almost every way. first one strand per follicle, then many (down) and then twisting together into harder spines (the sorts of feathers chicken feet grow). as the spines continue to twist, you start seeing strands extend from them. from there it's just barbules to aid in rigidity, and assymetry to aid in flight. we have examples of many of these types of feathers. we have a whole thread on the avian lung. it's a little hard prove definitively, since internal organs fossilize so rarely. but one thing is actually somewhat certain: theropod dinosaurs had lungs VERY similar to modern birds, and long before they could fly. we know this because many had pneumatized bones, like birds. in a bird skeleton, the hollow bones are actually linked to the respiratory system, via the air sacs. so the fact that a dinosaur like velociraptor has hollow bones means it almost certainly had air sacs as well. the system as a whole appears to have gone from a normal reptilian lung (lacking diaphragm), to a single-cycle air sac system, which used the sacs somewhat like a diaphragm. from there, the process just becomes two-cycle, instead of one. the curious point of this that all the while, dinosaurs remain "rib breathers." and that includes modern birds -- which still use the motion of their chests to aid respiration.you may want to look at my message 24 of that thread for a more complete explanation. Edited by arachnophilia, : typo

---

so you have no problem with the fact that whales are even-toed ungulates? in the same "kind" with hippos, pigs, llamas, camels, deer, sheep, goats, and antelope? ok. let's talk about tiktaalik, the fish with legs. i suppose he was "just created that way?"

---

tell that to those crazy flying reptiles with hair. internal organs are notoriously bad at fossilizing.what we can do is compare the bones we have in the rock with the bones of living animals. a dinosaur like velociraptor has the rib structure similar to a crocodile, a hip similar to a bird's in position, and the hollow bones of a bird. what do you suppose his innards looked like? evidently, he'd have a crocodilian lung -- as birds still do. but because of the hollow bones, he'd have air sacs like a bird.hard anatomy is a good hint at soft anatomy. you wouldn't seem a diaphragm and human lung inside a dinosaur skeleton. but you would see something related to both a crocodile and a bird.

---

you said that losing limbs was acceptable. and that must mean that a creature like pakicetus (the whale with legs) is still "just a whale." nevermind that he is an even-toed ungulate. i see at least one leg bone (maybe two), some rudimentary digits, and something like a lobed fin on the end. what's it look like to you? did you? seal flippers are limbs, with fully formed digits. above is one hindlimb of a seal. or, maybe they're more like the "limbs" of the coelacanth:which is more or less the same, with less distinct digits. its skull makes it a fish, if that's what you're trying to say. the neck connection, however, is more amphibian. however, he doesn't have enough of a leg to be a land creature. we was clearly something that lived in the shallows, and used his rudimentary limbs to scoot around ponds (and maybe from pond to pond as lungfish and even catfish today do) to greater advantage that just the lobe-finned fish.

---

again, tell that to this reptile that has hair: no, not the same SUBSTANCE. the same GENE. one gene produces both. by default, it produces feathers. with modifaction (addition of one gene) they become scutes in certain places. without the gene, they are feathers.

---

i pictured one above for you. his name is sordes pilosus, and he is a dimorphodon. which is a subdivision of pterosaurs, which alongside dinosaurs are archosaurs, which are sauropsids ("reptiles"). and it has hair, or at least something very, very similar to it. we can be nearly certain. an outside possibility, since one of the two features had to have developed first. no, see, that's the part i just went over. not all dinosaurs did, and the smaller theropods certainly did not. for instance, all deinonychosaurs (dromaeosaurs [velociraptor], troodons, archaeopteryx, and all modern birds) have hollow bones.Edited by arachnophilia, : typo

---

read more closely. mesonychus was the proposed ancestor to whales (differing very obviously in the teeth). pakicetus was the was find that overturned that hypothesis. have a look at the skulls again. pakicetus's skull is almost passable for a modern whale's skull, except for the location of the nostrils and eyes. we have all seen aig, i promise. i find them particularly dishonest on biblical matter, btw. we must have taken different anatomy and biology classes. and you won't in amphibians, either. (because those are PECTORAL fins -- forelimbs. not hind legs) yes. it's oddly between the two, isn't it? fish don't have flippers. they have fins. this one has exceptionally long lobed fins. that end in well definied digits.did you catch that? it has hands and fingers. no, they are not homologous to flippers. they are extended lobed fins. yes, it is. the distance between the "fin" and the body is two great to call it anything but a limb. it has a jointed apendage protruding from its torso, that ends in fingers. what would you call it?and it's not a flipper. maybe you don't know anything about biology? i made no claims about the rear end.

---

it's an archosaur. it's a reptile. do you doubt that pterosaurs are reptiles? what does it look like to you? they are actually mistaken. the chemical makeup of reptilian scales and bird feathers differ. if you don't believe me, well, check any creationist site on the question. they like to herrald that piece of evidence as proving that bird feathers couldn't have come from reptilian scales. which actually proves very little. yes, and refer to scutes, it is the same gene. that's the point i was making -- not only are those chemical compositions the same, but so are the genes.

---

if god created creatures, he did so in such a way that would change over time. that much, we have evidence for. by evolving follicles. i'm not sure i should even entertain this. it was a ridiculous idea when it was proposed in the 1850's, and it's even more ridiculous today. to fake all 7 specimens the same way, so that they all produce perfect replicas of perfectly aerodynamic feathers would literally require the hand of god. we are finding more and more features in archaeopteryx even today that they had no idea about in the 1850's -- and all new specimens match the first one. read all about it, here. only in the regard that new evidence is always being introduced, and that science doesn't actually PROVE anything. yeah, let's look at those.

quote:

---

These so-called differences exist between dinosaurs classified as Saurischian (reptile-like, hip-girdled species) and Ornithischian (bird-like, hip-girdled species). This concept of dinosaurs having hip girdles similar to those of birds is now and then taken as evidence for the alleged dinosaur-bird link. However, the difference in hip girdles is no evidence at all for the claim that birds evolved from dinosaurs. That is because Ornithischian dinosaurs do not resemble birds with respect to other anatomical features. For instance, Ankylosaurus is a dinosaur classified as Ornithischian, with short legs, a giant body, and skin covered with scales resembling armor. On the other hand, Struthiomimus, which resembles birds in some of its anatomical features (long legs, short forelegs, and thin structure), is actually a Saurischian.110

---

huge fallacy. this is going to sound weird, but guess which kind of hip bones modern birds have? if you guessed "ornithstician" you just lost. the ornithstician dinosaurs were so named because the people who first found them thought the hips looked like those of birds. in fact, modern birds are actually saurischian dinosaurs.in ornithsticians, the pubis has a forward projection. saurischians (including birds) lack this projection. the original distinction was made based on whether the pubis was parallel or perpendicular to the ischum. in reptiles, it is perpendicular. in birds, it is parallel. the problem is that we have many "lizard-hipped" dinosaurs with pubi in various stages of turning backwards. that velociraptor i keep mentioning is a good example. not suprisingly, so is archaeopteryx.this page has some nice illustrations for you.

quote:

---

Dinosaur bones are thick and solid because of their massive structure, whereas the bones of living and extinct birds are hollow, and thus very light.

---

as previously mentioned, many non-avian dinosaurs have hollow bones.

quote:

---

Another difference between reptiles and birds is their metabolic structure. Reptiles have the slowest metabolic structure in the animal kingdom. (The claim that dinosaurs had a warm-blooded fast metabolism remains a speculation.)

---

it's not speculation. it's reasonable inference. name me a cold-blooded animal that walks on two legs? i bet you can't do it. in fact, name me a cold blooded animal that walks on four legs, but with its legs fully underneath its body. there's a REASON you can't do it: none exist, because none CAN exist. cold-blooded animals have to stick close to the ground for warmth.any animal that walks upright has to be warm-blooded, otherwise it dies of heat loss.

quote:

---

One of the best-known ornithologists in the world, Alan Feduccia from the University of North Carolina, opposes the theory that birds are related to dinosaurs, despite the fact that he is an evolutionist himself.

---

of all the names to drop, feduccia is the worst. in the paleontology community, people LAUGH at him. i'll look and see if i can find you an example of his proposed ancestor for birds -- but they look something like chameleons. he even alleges that archaeopteryx is a true bird, but not at all related to dinosaurs (even though it's skeleton is identical to every other maniraptoran dinosaurs in almost every way).added by edit: you might want to have a look at this thread on archaeopteryx and avian dinosaurs for more information.Edited by arachnophilia, : No reason given.

---

actually, that's dna's primary function. replication. it's one of the few things that DOES make itself. poor cyrptology. some combinatorists i know would be appalled. there is a difference between a string of data, and a message. now, if the human genome could be decoded into a message that contained all five books of the torah -- i'd jump right on the id bandwagon.

---

technically, we are just tools to facilitate the replication of dna. in the same way that static in between the radio stations is data. it is, btw. we can actually tell something about our own sun with it, too.presence of data does not indicate intelligent origin. otherwise, seti would make headlines every other day when they discover a new pulsar. on the contrary, the evidence and testing cannot support anything else. observation confirms it. genetics confirms it. paleontology confirms it. cladistics confirms it. any competing theory has to now explain all of the confirmed predictions, and predict something new that differs from evolution, and confirm that prediction.an "last thursdayism" doesn't count as an explanation. when the titles of the sources are "evolution" "the case against creationism" etc, and the authors are some of the biggest voices in evolutionary biology, and paleontology, and they're being quoted as saying things against evolution, you can bet your whiskey jar, hat, and suspenders that they're being quotemined in extreme.

---

as your posts here have illustrated, you have been completely mislead about evolution and biology in general, and you keep repeating common low-level creationist pratts -- points refuted a thousand times. false, and also a bad picture of what paleontology is. you're thinking of this lie by aig:yet as even aig shows in another graphic, there is considerably more of the pakicetus skeleton than that: the reason it's a bad representation of palenontology is that it completely misrepresents the science behind a skeletal reconstruction. we do not have pakicetus in isolation, and they are not just making stuff up out of thin air.rather, we have another animal that looks nearly exactly like pakicetus: ambulocetus. the bones are homologous to a high enough degree that a reasonable guess at the missing segments can be made.this is not circular logic. if evolution were not true, scientists would not be able to do this. no, i emphasized a word for a reason. it's the important word. they are PECTORAL, not HIND limbs. they do not have ball and socket joints or kneecaps. no tetrapod -- including you -- has a ball and socket joint for your shoulder, and a kneecap in your elbow. so it's a fish, with a leg? this is what i mean about having no knowledge about biology in general. it's not a seal-like creature. seals are mammals. this is something with a skull showing both fish and amphibian anatomy, an amphibian neck joint, gill structurs, and stubby legs that highly resemble lobed fins (as in a coelacanth) that would have been largely incapable of walking on land. i did. there's a picture a few pages back. i can be sure, because i know what a flipper, a hand, and a fin are. just because you know very little about anatomy doesn't mean the scientists don't either. i'll remember not to bring up chemistry or physics then. if you found half a fish, would you be able to guess at what the rest looked like? if you found half a newt, would you be able to guess at what the rest looked like? if you found half something that looked like both a newt and a fish, would the rest of it be important to telling you it was something similar to both a fish and a newt?Edited by Admin, : Reduce image width.

---

*sigh* no. it's not a bird. it's a pterosaur.all birds are archosaurs. but not all archosaur are birds. archosauria is the group that includes dinosaurs, crocodiles, pterosaurs, and (maybe) marine reptiles. "birds" is actually redundant, because dinosauria is a group that includes birds.the animal we were looking at is not a bird at all. actually, it is. it's hard to do it an be convincing. one, maybe, could be faked. but *all* the pterosaurs we have with hair? and all of the dinosaurs with feathers? the same way anything else fossilized. by making an impression that fills with minerals. hair (and feathers) don't fossilize very well either. it doesn't mean they DON'T. because it's such a minor one, and it's not my job to go around correcting every herpetology website about tiny errors. yes.Dinosauria On-Lineif you remove a single gene from the chicken genome, the scutes on their feet are replaced by feathers. this gene is the one that modifies feathers into scutes. one gene. except, of course, for the fact that they do have a lot to do with feathers, if we can fairly easily turn them into feathers. we also have some dinosaurs, like microraptor gui, that have flight feathers on their feet, growing from where modern birds have scutes: no, please try to follow along.the reptilian scales on a bird's feet, which are located on the bottom of the foot, are not the same chemical composition as feathers. the bird scales on a bird's feet, SCUTES, which are located on the top of the foot, ARE.

---