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Sat 5 Feb, 2005 06:15 am
Down feathers are for insulation. It isn't hard to picture down feathers having arison as some sort of a mutation from hair. In fact it isn't hard to picture down feathers on some dinosaurs; in fact it isn't hard to picture the tyrannosaur as having been some sort of a proto-bird with down feathers.
The thing which could NOT in any way plausibly arise from hair OR down feathers in any manner not involving intelligent design is FLIGHT feathers. Flight feathers have complex structure like the built-up structure of airplane wings in which strength is derived from almost weightless components, and involve a complex system of interlatched barbs and barbules:
http://www.paulnoll.com/Oregon/Birds/feather-flight.html
http://www.answersingenesis.org/tj/v17/i1/feathers.asp
Aside from the intricate and complex structure of the flight feathers themselves, there is the intricate system in which they are opened and closed like venetian blinds on upstrikes and downstrokes; air passes between the flight feathers on upstrokes. That means that they are turning on their pivots.
Now, obviously, all this stuff had to work on the very first day that any bird ever flew, andf could not possibly evolve since evolution cannot possibly produce something like that by degrees for a future need.
Evolutionists will point to flightless birds and claim they are future flying birds in progress, but the answer is that they are basically birds which have LOST the ability to fly, usually by having become too heavy. Moreover there is zero evidence of any sort of an ostrich or emu or any such ever having even thought about regaining the ability to fly. Once you lose some complex ability like that, it's gone forever.
The concept that birds and some dinosaurs have a whole bunch of similarities that overlap just seems to escape you. The dromeaosaurs which bud out to raptors and birds seems to indicate that birds didnt rise from dinosaurs , but that both rose from an ancestor that had all of the following ;
feathers
hollow bones
5 sacral vertebrae
a secondary bony palate
a wishbone clavicle
a large air filled sinus
a forward pubic bone
flexible wrists
a long curved carpal bone
ankles off ground
similar crown construction on the teeth
Theres about 20 + similarities that cross from dromeaosaurs to birds.
There are, among birds , quite a number of feather mods from birds that only live in specific parts of the world, like islands.
The concept of flight fethers needs to consider the 4th element in evolution, which is Time for adaptation. Maybe first flight was nothing more than a quick glide like a chicken, coupled with a short drumming motion of the wings. Earliest birdlike dino fossils show that these "birdosaurs" were able to climb because they had extensions of their "finger bones" external to the last hand joint.
Over time, birds were selected for flight or running (usually not both) we see fossils of large flightless birds from the Paleocene of South America. At that time, 63 million years ago, SOuthAmerica was a huge island,broken off from PAngea but still not yet reconnected to the rest of the hemisphere, so many weird forms , unique to that environment, developed after the demise of the Dinoaurs , among these were a significant number of large flightless bird species found nowhere else on earth. hese were huge running birds with great hooked beaks for tearing flesh. ( they didnt eat worms)
Goulds work on the flight of insects in the Carboniferous shows a similar development of flight in a totally different wing design. Earliest insect fossils of the family that included ancient dragonflies clearly show that the first fossils were incapable of flight and that the earliest stubby "wing" appendages were probably used for moving air over their spiracles because these insects were large and teetered on the edge of no respiration. So fossils of the short winged ones were less successful than the longer winged ones. Given enough time, the longer winged dragonflies were more and more successful because cluster analyses of fossils show that the stubby winged disappeared early.
Maybe one day, in Early Pennsylvanian time, a dragonfly with long wings was sitting there cooling and ventilating when , he suddenly began to lift.
Of course its speculation , but the process of using data and evidence is more sound than settling on some legend that is first accepted blindly and , then, if you are lucky, maybe try to find some evidence. However, even absent any evidence worth considering, the ID students seem to still try to support their legend based science system.
Farmerman - could you recommend a good book for catching up with where evolutionary theory is at?
The best reference text that is quite approachable is Mayrs WHAT EVOLUTION IS
I use some other texts for classes in "problems" , I like Dawkins new work THE ANCESTORS TALE, its very creatively laid out like THECANTERBURY TALES,
MOLECUALR MARKERSM NATURAL HISTORY, and EVOLUTION , by John AVise is good also.
Feduccias book THE ORIGIN AND EVOLUTION OF BIRDS, which gunga tries to quote but misses the point, is a hypothesis that birds and dinosaurs had a common ancestor and one didnt arise from the other. Its a topic for discussion at a symposium that presents and analyzes evidence. Its not, as gunga seems to want , A solid indictment that dinos begat birds. There was never a consensus that such an exlanation was accepted bythe community. That was a generalization by Bob Bakker and was a line from Jurassic Park. The dromaeosaurs overlap birds and dinosaurs, to deny that they werent evolutionary partners defies reason.
A Book Id stay awy from is Goulds last work on the Structure of Evolutionary Theory. This book was rushed and poorly edited , and its ponderous. At the time of first edits, Gould was already dying from Cancer and the book has no real flow. It a rather loose, but brilliant , collection of ideas, evidence, and asides that often diverts from the main topic , it never gets back.
The role of extinction is important in evolution , and Dave Raups 1991 book EXTINCTION_BAD LUCK OR BAD GENES, sounds like a lightweight book. It is short and well written and , even entertaining. Its gonna be a classicon the entire subject of extinctions and the fossil record.
Start with Mayr , then go to Dawkins
Thank you!!! Oddly, I was looking at Gould today.
Any really good (and approachable!) stuff online - while I am asking?
I have good lay biology - but no study of it at university level.
the talk origins archives and answers in genesis are good sites to get both sides of an issue.
all the niversities have web sites (edu) with research reports. The national council for science education is an advocasy site. also there are a bunch of bad science sites like Badgeology.org, bad chemistry.org etc. Im really not the one to ask about online sits because Im usually hunting for one thing at a time and some of the U sites get really arcane.
The Dawkins book has a great ref section which includes URLs
farmerman wrote:The concept that birds and some dinosaurs have a whole bunch of similarities that overlap just seems to escape you.
The thing which clearly escapes you is the notion that all change need not be EVOLUTIONARY change, i.e. that birds might have been RE-ENGINEERED from dinosaurs, instead of EVOLVING from them which, as I note in the case of flight feathers, is clearly impossible.
evidence would help.
whether you know it or not, youre slowly becoming a convert to evolution, you just want to call it something else. Thats ok, you trip yourself up by implying an outside force which, in my own cross exam of you would be, who or what is this outside force?
gungasnake wrote:instead of EVOLVING from them which, as I note in the case of flight feathers, is clearly impossible.
Just because you don't understand how it could happen doesn't make it impossible.
gungasnake wrote:The thing which clearly escapes you is the notion that all change need not be EVOLUTIONARY change, i.e. that birds might have been RE-ENGINEERED from dinosaurs
Who or what did the re--engineering you speak of?
And how was the re-engineering accomplished?
Please be specific.
Re: Flight Feathers
gungasnake wrote:The thing which could NOT in any way plausibly arise from hair OR down feathers in any manner not involving intelligent design is FLIGHT feathers.
Now, obviously, all this stuff had to work on the very first day that any bird ever flew.
Wrong. What fool told you that?
You can't picture feathers coming in a range of shapes and sizes, and flat feathers on the arms benefitting the agility of small light dinosaurs or proto-birds? That's all it takes to get a preponderance of flat feathers is a slight benefit in reproductive success. Then with variation in flat feather overlap growth, the agility of the animal happens to improve even more, and once again, there is a preponderance of sealed flat feathers due to reproductive success. And then one of those dinosaurs decides to jump for its life from a tree one day, and it happens to glide better than whatever is after it, or it simply survives the fall.
gungasnake wrote:Evolutionists will point to flightless birds and claim they are future flying birds in progress
No they don't. Now you're just making stuff up. Most naturalists are well aware that flightless birds lost the ability to fly, and I have never heard anyone suggest that they are headed back the other direction (even though it's obviously quite possible they could). Where the hell did you hear that? Are you getting your information from reputable sources, or from creationist web sites.
I dont think that gunga reads any of our posts at all. Im convinced of this.
farmerman wrote:I dont think that gunga reads any of our posts at all. Im convinced of this.
Every now and then it hisses out a feeble answer to one of our challenges, but I admit, it's rare to get a really meaningful reply. Usually it's just evasion or rhetoric.
Rex the Wonder Squirrel even tried to scare the snake out of its hole with a challenge to its approach for defending creationism, but Gunga just slithered away
I see that ErnstMayr died and I was wondering if anyone could find and post his obotuary from the NYT?
http://www.nytimes.com/2005/02/05/science/05mayr.html
It's 3 pages long -- would you like me to post the whole thing?
Ernst Mayr, Pioneer in Tracing Geography's Role in the Origin of Species, Dies at 100
By CAROL KAESUK YOON
Published: February 5, 2005
Dr. Ernst Mayr, the leading evolutionary biologist of the 20th century, died on Thursday in Bedford, Mass. He was 100.
Dr. Mayr's death, in a retirement community where he had lived since 1997, was announced by his family and Harvard, whose faculty he joined in 1953.
He was known as an architect of the evolutionary or modern synthesis, an intellectual watershed when modern evolutionary biology was born. The synthesis, which was described by Dr. Stephen Jay Gould of Harvard as "one of the half-dozen major scientific achievements in our century," reconciled Darwin's theories of evolution with new findings in laboratory genetics and in fieldwork on animal populations and diversity.
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One of Dr. Mayr's most significant contributions was his persuasive argument for the role of geography in the origin of new species, an idea that has won virtually universal acceptance among evolutionary theorists. He also established a philosophy of biology and founded the field of the history of biology.
"He was the Darwin of the 20th century, the defender of the faith," said Dr. Vassiliki Betty Smocovitis, a historian of science at the University of Florida.
In a career spanning nine decades, Dr. Mayr, a professor emeritus of zoology at Harvard, exerted a broad and powerful influence over the field of evolutionary biology. His most recent book, "What Makes Biology Unique?: Considerations on the Autonomy of a Scientific Discipline" (Cambridge University Press), was published in August, one month after his 100th birthday.
Prolific, opinionated, provocative and dynamic, Dr. Mayr had been a major figure and intellectual leader since the 1940's. Setting much of the conceptual agenda for the field, he put the focus just where Charles Darwin first placed it, on the question of how new species originate.
Though Dr. Mayr will be best remembered as a synthesizer and promoter of evolutionary ideas, he was also an accomplished ornithologist. In fact, it was with the sighting of a pair of unusual birds that Dr. Mayr's long career in biology began in 1923 at age 19.
Dr. Mayr was born in Kempten, Germany, in 1904. While still a boy, he was instructed in natural history by his father, Otto, a judge. He quickly became a skilled birdwatcher and naturalist. Intending to become a medical doctor like others in his family, Dr. Mayr was about to leave for medical school when he spotted a pair of red-crested pochards, a species of duck that had not been seen in Europe for 77 years.
Though he took detailed notes, he could not get anyone to believe his sighting. Finally, he met Dr. Erwin Stresemann, then the leading German ornithologist, who was at the Berlin Zoological Museum and who recognized his talents and invited him to work at the museum during school holidays.
After two years of medical studies at the University of Greifswald (chosen because it was in the most interesting German region for birdwatching), Dr. Mayr, like Darwin before him, opted for natural history. He completed his Ph.D. at the University of Berlin in just 16 months.
Dr. Mayr went on to fulfill what he called "the greatest ambition of my youth," heading off to the tropics. In the South Pacific, principally New Guinea and the Solomon Islands, Dr. Mayr collected more than 3,000 birds from 1928 to 1930. (He had to live off the land, and every bird, after being skinned for study, went into the pot. As a result, he is said to have eaten more birds of paradise than any other modern biologist.)
The South Seas experience, he once said, "had an impact on my thinking that cannot be exaggerated." For it was his detailed observations of the differences among geographically isolated populations that contributed to his conviction that geography played a crucial role in the origin of species.
Though Darwin titled his book "The Origin of Species," little in the book, in fact, addresses the question of how new species arise. Dr. Mayr determined that when populations of a single species are separated from one another, they slowly accumulate differences until they can no longer interbreed. Dr. Mayr called this allopatric speciation and detailed his arguments in his seminal book "Systematics and the Origin of Species," published in 1942. Today allopatric speciation ("allo," from the Greek for "other," and "patric," from the Greek for "fatherland") is accepted as the most common way in which new species arise.
soz, is it possible to PM me with it. I cannot get into NYT ever since the little abuzz uhhh... misunderstanding, words were said, things were promised, lawyers exchanged business cards.
Thanks bobsmythawk, I wanted to download the entire NYT one because I understand it had some of the Dobzhansky controversy and the arguments that Mayr and the Gould had about "Punctuated equilibrium" of which Mayr was not a supporter and, seems to be going his way.
Its amazing that at one time ecologists argued much about allopatric speciation even though this is one of the areas of evolution thatwe can actually observe in nature
Lawyers exchanged business cards!! Oh my!! You can't even let you access the site? How weird.
I cant talk about the unpleasantness, its kinda a lesson for me
Thank you for the obituary, It covered all the bases I had a correspondence with he and Gould in the m,id 1980s when we found a new series of graptolites at a mineral exploration site. They were both like a bunch of eager kids to share ideas and before long, it got very seductive to be carrying on communications with these two giants. (may I say, that both of these men were multidimensional , in that their interests spanned the sciences and art and even sports (Gould as a walking encyclopedia of the Yankees Dodgers and the Cubs. Mayr was a student of the Bauhaus)