Originally Posted by Deanstar
Well I agree that you could somehow manipulate them in a limited way in a lab, but I don't agree that they evolve. I think any changes are small and just naturalistic based on the genetic blueprints.
Well - I guess, that's a start. What you had thrown up somewhere before, was that such "genetic manipulation" would only decrease or shift the abilities of organisms - but in that Nature paper, I linked a review to (a multi-national effort, that project) - they mention it explicitly how these E. coli got better adapted while evolving over 20.000+ generations. That was the aim of the study - showing how natural selection having it's way brings about actual benefits. This number 20.000+ is a reason, why you can't see it from your armchair - a lot of reproduction goes down before something significantly changes.
Originally Posted by Deanstar
Just looking face value at the pictures. Does it really look anything like a planet forming? Or does it look more like a bit of a dust cloud of some sort? What is it? If this is a planet forming where are the other stages of it? Cause this is about the cloud stage isn't it? I don't think there is a process observed where a planet actually forms, and I don't believe these pictures represent that in any way whatsoever. But if I am wrong I would prefer something a little more explainable.
You are right - these are dust and gas clouds!
My pictures show clouds, in which new stars formate, not planets, that works differently again, see below. I'll copy out from that NASA link above, which states the fact and explains a little:
Originally Posted by NASA
Stars
Stars are the most widely recognized astronomical objects, and represent the most fundamental building blocks of galaxies. The age, distribution, and composition of the stars in a galaxy trace the history, dynamics, and evolution of that galaxy. Moreover, stars are responsible for the manufacture and distribution of heavy elements such as carbon, nitrogen, and oxygen, and their characteristics are intimately tied to the characteristics of the planetary systems that may coalesce about them. Consequently, the study of the birth, life, and death of stars is central to the field of astronomy.
Stars are born within the clouds of dust and scattered throughout most galaxies. A familiar example of such as a dust cloud is the Orion Nebula, revealed in vivid detail in the adjacent image, which combines images at visible and infrared wavelengths measured by NASA's Hubble Space Telescope and Spitzer Space Telescope. Turbulence deep within these clouds gives rise to knots with sufficient mass that the gas and dust can begin to collapse under its own gravitational attraction. As the cloud collapses, the material at the center begins to heat up. Known as a protostar, it is this hot core at the heart of the collapsing cloud that will one day become a star. Three-dimensional computer models of star formation predict that the spinning clouds of collapsing gas and dust may break up into two or three blobs; this would explain why the majority the stars in the Milky Way are paired or in groups of multiple stars.
As the cloud collapses, a dense, hot core forms and begins gathering dust and gas. Not all of this material ends up as part of a star — the remaining dust can become planets, asteroids, or comets or may remain as dust.
In some cases, the cloud may not collapse at a steady pace. In January 2004, an amateur astronomer, James McNeil, discovered a small nebula that appeared unexpectedly near the nebula Messier 78, in the constellation of Orion. When observers around the world pointed their instruments at McNeil's Nebula, they found something interesting — its brightness appears to vary. Observations with NASA's Chandra X-ray Observatory provided a likely explanation: the interaction between the young star's magnetic field and the surrounding gas causes episodic increases in brightness.
Here's a source with pictures and some more explanations from a physics department: The Birth of Stars
He explains it very nicely - from UniverseToday:
But you will find much more about it, if you look - just google star formation, and you'll get to such sources, they abound.
Originally Posted by Deanstar
My awe is of a different sort In my mind I am thinking how can you possibly think that it is to do with a planet? Cause that is amazing that some fluffy cloud (that could it even be photo manipulated perhaps? is evidence that they form into solid planets? Beyond this so called cloud stage I don't see anything. If this theory is correct there sould be many clouds whirling around in different stages of being a complete planet.
Again - this is about stars, not planets. And I'm awed by the sheer size and beauty of these clouds - combined with the thought, that actual stars are forming in them, stars like our sun. While star formation is understood and we can observe it - with planets there seem to be some questions open, this is what Wikipedia has to say on their formation:
Originally Posted by Wikipedia
It is not known with certainty how planets are formed. The prevailing theory is that they are formed during the collapse of a nebula into a thin disk of gas and dust. A protostar forms at the core, surrounded by a rotating protoplanetary disk. Through accretion (a process of sticky collision) dust particles in the disk steadily accumulate mass to form ever-larger bodies. Local concentrations of mass known as planetesimals form, and these accelerate the accretion process by drawing in additional material by their gravitational attraction. These concentrations become ever denser until they collapse inward under gravity to form protoplanets. After a planet reaches a diameter larger than the Moon, it begins to accumulate an extended atmosphere, greatly increasing the capture rate of the planetesimals by means of atmospheric drag.
When the protostar has grown such that it ignites to form a star, the surviving disk is removed from the inside outward by photoevaporation, the solar wind, Poynting–Robertson drag and other effects. Thereafter there still may be many protoplanets orbiting the star or each other, but over time many will collide, either to form a single larger planet or release material for other larger protoplanets or planets to absorb. Those objects that have become massive enough will capture most matter in their orbital neighbourhoods to become planets. Meanwhile, protoplanets that have avoided collisions may become natural satellites of planets through a process of gravitational capture, or remain in belts of other objects to become either dwarf planets or small bodies.
It really does fill me with awe! Us small humans on a little planet in the outskirts of an insignificant galaxy - we are able to find these things out - watch them happen, learn about the workings of the universe so that our knowledge enables us to produce working technology on such a gigantic scale as we do. Even a cell-phone would have seemed like divine magic to our forefathers, heck - a sophisticated piece of modern clothing would! Hubble Space Telescope and it's pictures would have right-out blown their minds!
If there was a god, willing and able to reveal stuff to humanity - why didn't he reveal something more interesting and useful than he did? Let us in on scientific knowledge about how his creation actually works, instead of waiting for us to find out on our own, how it can't have happened the way the bible says?
How is it - does it contradict the bible, that stars are born and die? I guess it does, because it is peculiar, that you wouldn't be aware of it yet otherwise. Could it be, that you've been indoctrinated with something like: "Stars have been created at the beginning by god, and there are no new ones coming into being any more"? Is that Creationist doctrine? If so - I guess this reality comes as a mighty surprise.
Originally Posted by Deanstar
I think we should remember that species is much stranger definition than different kind of animal. With 'species' even a little change can be called a different kind. With a different type of animal in general though they have to be able to re-produce with each other. If it becomes a case that two dogs can no longer breed with each other for example, I see that as not evolution, but the genetic blueprint reaching it's limitation. Different kind of animals will never be able to re-produce with each other, and any genetic variation never allows for that. This is why there can't be evidence of macro-evolution. Because things like cats and dogs can never breed with each other and there is definitely no evidence that a cat came from a dog. As it goes for the rest of the animals too.
When you talk about fruit flies, again that is some artificial manipulation of a genetic blue print. The fruit flies can actually recover quickly when you leave them alone.
What you are talking about is that hybrids tend to be sterile, right? Like that plant in the link I spoilered out above. But what would it be, if you found some dogs on a newly discovered island, which somehow escaped scrutiny from explorers for thousands of years*. Say the dogs were left there by an ancient civilisation and had sufficient time to evolve and a specific need to adapt to that island, too.
Now - there will be some, who are already a bit adapted, and they have more success at procreation of abundant and viable offspring, while the others die off, etc, etc. Now you come with your boat and find some critters very much looking like dogs, but they are unusual, not only varying in what us humans are interested in when crossing dogs, but they have clearly gained some function other dogs/wolfs don't have, too. And it's an adaptation, it can be understood as being beneficial to them because of the special features of the island. They have an ability, no usual dog has a use for - say going vegetarian - bit extreme - but why not, with meat resources dwindling in just the right rate - like the Panda bear, also a secondary plant eater - not with four stomachs and having a lot of eating to do?
So then you take them with you and to your chagrin - your vegetarian "dogs" can't reproduce with any other dogs any more - but with each other they can!
Eureka?
Would that constitute a new species having evolved in your eyes?
Ah - exactly - it would be good, if you gave a hypothetical case in which you would indeed diagnose "evolution"!
I could come up with scenarios (and did in my Atheism thread), which would justify a diagnosis of "a god did it" in my eyes. If she/he/it pretended to be the Christian god - I would feel like accusing him of obscurantism, but that's another thought.
Okay - article next portion:
Originally Posted by Creationist article, Morris
Evolution Never Happened in the Past
Evolutionists commonly answer the above criticism by claiming that evolution goes too slowly for us to see it happening today. They used to claim that the real evidence for evolution was in the fossil record of the past, but the fact is that the billions of known fossils do not include a single unequivocal transitional form with transitional structures in the process of evolving.
Given that evolution, according to Darwin, was in a continual state of motion . . . it followed logically that the fossil record should be rife with examples of transitional forms leading from the less to the more evolved.
Even those who believe in rapid evolution recognize that a considerable number of generations would be required for one distinct "kind" to evolve into another more complex kind. There ought, therefore, to be a considerable number of true transitional structures preserved in the fossils -- after all, there are billions of non-transitional structures there! But (with the exception of a few very doubtful creatures such as the controversial feathered dinosaurs and the alleged walking whales), they are not there.
Instead of filling in the gaps in the fossil record with so-called missing links, most paleontologists found themselves facing a situation in which there were only gaps in the fossil record, with no evidence of transformational intermediates between documented fossil species.
There are transitional life forms and more and more are being found. The feathered dinosaurs are not controversial, neither the fact, that birds evolved from dinosaurs - you've been belittling that idea - but please re-check the National Geographic link on feather evolution, I provided - you find transitional stages of dinosaurs with "almost-feathers" in that matter as well.
Creationists had for ages been clamouring, why we wouldn't find a fish with feet - the Darwin Fish (not Jesus fish - my bad). Well - we did find dozens of them. And not only that - evolutionary theory lead to scientists predicting, where exactly they might find it - and they did:
Your Inner Fish: Book and PBS documentary on Tiktaalik and Neil Shubin.
I really recommend giving it due consideration:
Originally Posted by Slate
We all know the Darwin fish, the car-bumper send-up of the Christian ichthys symbol, or Jesus fish. Unlike the Christian symbol, the Darwin fish has, you know, legs.
But the Darwin fish isn't merely a clever joke; in effect, it contains a testable scientific prediction. If evolution is true, and if life on Earth originated in water, then there must have once been fish species possessing primitive limbs, which enabled them to spend some part of their lives on land. And these species, in turn, must be the ancestors of four-limbed, land-living vertebrates like us.
Sure enough, in 2004, scientists found one of those transitional species: Tiktaalik roseae, a 375-million-year-old Devonian period specimen discovered in the Canadian Arctic by paleontologist Neil Shubin and his colleagues. Tiktaalik, explains Shubin on the latest episode of the Inquiring Minds podcast, is an "anatomical mix between fish and a land-living animal."
"It has a neck," says Shubin, a professor at the University of Chicago. "No fish has a neck. And you know what? When you look inside the fin, and you take off those fin rays, you find an upper arm bone, a forearm, and a wrist." Tiktaalik, Shubin has observed, was a fish capable of doing a push-up. It had both lungs and gills. In sum, it's quite the transitional form.
Shubin's best-selling book about his discovery, Your Inner Fish: A Journey Into the 3.5-Billion-Year History of the Human Body, uses the example of Tiktaalik and other evolutionary evidence to trace how our own bodies share similar structures not only with close relatives like chimpanzees or orangutans, but indeed, with far more distant relatives like fish. Think of it as an extensive unpacking of a famous line by Charles Darwin from his book The Descent of Man: "Man still bears in his bodily frame the indelible stamp of his lowly origin."
"Many of the muscles and nerves and bones I'm using to talk to you with right now, and many of the muscles and nerves and bones you're using to hear me with right now, correspond to gill structures in fish," explained Shubin on Inquiring Minds. Indeed, despite having diverged from fish several hundred million of years ago, we still share more than half of our DNA with them.
"The genetic toolkit that builds their fins is very similar to the genetic toolkit that builds our limbs," Shubin says. "And much of the evolution, we think, from fins to limbs, didn't involve a whole lot of new genes."
Now, of course, none of this sits well with the young-Earth creationist crowd, who are continually trying to undermine science education and U.S. science literacy. What do creationists say about Shubin's research, and especially Tiktaalik? Turns out that creationist Ken Ham of Answers in Genesis has his answer ready to go: "There are no transitional forms that support evolution," he confidently declares in a minute-long audio track dedicated to debunking the Tiktaalik finding. Why? Because "the Bible says God made fish and land animals during the same week, not millions of years apart." That's just the beginning of the attempted takedowns that creationists have leveled against Shubin's work.
Pictured near where it was found is a Tiktaalik roseae fossil — one of the most complete of the dozens of specimens discovered to date.
Tiktaalik roseae, a 375-million-year-old Devonian period specimen discovered in the Canadian Arctic by paleontologist Neil Shubin and his colleagues.
Photo courtesy PBS
Creationists snipe, raise doubt, and deny almost everything that we know, but the reason that Tiktaalik is such a momentous find appears to be beyond them: Evolutionary theory (complemented by an extensive knowledge of geology) predicted not only that this fish would have existed, but also that its fossilized remains would probably be found within a specific part of the world, in geological layers of a particular age. Hence, Shubin's many trips with his team to the Canadian Arctic, where those rock layers could be found. "We designed this expedition with the goal of finding this exact fossil," explains Shubin. "And we used the tools of evolution and geology as discovery tools to make a prediction about where to look. And the prediction was confirmed." Tiktaalik isn't just proof of evolution; it's also proof that the scientific process works.
Nevertheless, following the announcement of Tiktaalik's discovery in 2006, the creationists pounced. "My inbox is filled with some interesting emails," says Shubin. Over time, as the idea for Your Inner Fish began to gel, Shubin decided to seek out creationists, or less-than-evolution-friendly audiences, in person to try to explain the fossil and what it means. "I decided at that point, I'm going to go give talks in Alabama, in South Carolina, in Oklahoma, in Texas, and elsewhere, where I'll bring Tiktaalik with me, or the cast of Tiktaalik," says Shubin. "And I've done this every year."
Having the fossil to show, says Shubin, changes the entire nature of the discussion. "It's about the data, it's about the evidence, it's about the discovery," he says. "It's about, 'How do you date those rocks, how do you compare that creature to another creature?' Well, if we do that, we kind of win, because what it means is it changes the conversation in a way where it's now about evidence," he continues. "You're not going to change everybody's mind, but you're going to affect a few, most definitely. And that's kind of my passion. That's what I think I can bring to the table."
Yeah - well - I guess, this does speak for itself, esp. what I fattened. That you need not evolve a new toolkit for making limbs instead of fins is also interesting, you see, it's easier to evolve "new features", when you can build them from pre-existing mechanisms. That such things pre-exist also confines evolution to a degree - it doesn't start all over again from scratch, but further differentiates, what was there already in a more primitive form. Why not as many transitional forms as other fossils? Well - look back to that video which fact-checked Ken Ham. What you learn, is that speciation is usually happening in a bottleneck situation, when population sizes are thinned out, and then later the new species stabilizes and gets bigger and bigger. There simply were not as many of those there, also not "needed", which is logical, if you consider, how it comes to pass. There's development for so and so long, and then stability for much, much longer - equals more fossils - until the next major environmental upheavals.
Originally Posted by Creationist article, Morris
The entire history of evolution from the evolution of life from non-life to the evolution of vertebrates from invertebrates to the evolution of man from the ape is strikingly devoid of intermediates: the links are all missing in the fossil record, just as they are in the present world.
With respect to the origin of life, a leading researcher in this field, Leslie Orgel, after noting that neither proteins nor nucleic acids could have arisen without the other, concludes:
And so, at first glance, one might have to conclude that life could never, in fact, have originated by chemical means.
Being committed to total evolution as he is, Dr. Orgel cannot accept any such conclusion as that. Therefore, he speculates that RNA may have come first, but then he still has to admit that:
The precise events giving rise to the RNA world remain unclear. . . . investigators have proposed many hypotheses, but evidence in favor of each of them is fragmentary at best.
Translation: "There is no known way by which life could have arisen naturalistically." Unfortunately, two generations of students have been taught that Stanley Miller's famous experiment on a gaseous mixture, practically proved the naturalistic origin of life. But not so!
Miller put the whole thing in a ball, gave it an electric charge, and waited. He found that amino acids and other fundamental complex molecules were accumulating at the bottom of the apparatus. His discovery gave a huge boost to the scientific investigation of the origin of life. Indeed, for some time it seemed like creation of life in a test tube was within reach of experimental science. Unfortunately, such experiments have not progressed much further than the original prototype, leaving us with a sour aftertaste from the primordial soup.
Here is a classical misconception. As I said before, the emergence of life from non-living chemistry is called abiogenesis, and has got nothing to do with evolution. Whatsoever. Evolution only starts, once you have a single-celled organism, but it does tell you nothing, not even hypotheses, as to how that life came into existence. We do have good hypotheses for that as well - but it's a different topic, and it gets always conflated with evolution by Creationists, because abiogenesis is indeed one of the phenomena, we're not able to definitively explain - we don't yet know enough. But seriously - it's just trying to distract people, if you throw that in under evolution.
Originally Posted by Creationist article, Morris
Neither is there any clue as to how the one-celled organisms of the primordial world could have evolved into the vast array of complex multi-celled invertebrates of the Cambrian period. Even dogmatic evolutionist Gould admits that:
The Cambrian explosion was the most remarkable and puzzling event in the history of life.
Equally puzzling, however, is how some invertebrate creature in the ancient ocean, with all its "hard parts" on the outside, managed to evolve into the first vertebrate -- that is, the first fish-- with its hard parts all on the inside.
Yet the transition from spineless invertebrates to the first backboned fishes is still shrouded in mystery, and many theories abound.
I didn't yet look that up - but the fact, that we can't properly reconstruct every single sequence of happenings just means that - we can't yet explain every single aspect of it - but with time more and more of these "mysteries" get resolved.
Ah - but now I did look it up - and tadaa - the respective transitional form is called "Pikaia" - not a mystery at all (any more). This article practically has ten "missing links" with text and pictures - so it makes for a fine reply to this segment of the Morris article: 10 Missing Links in Vertebrate Evolution
Originally Posted by About/Education
10 Missing Links in Vertebrate Evolution
As useful as it is, the phrase "missing link" is misleading in at least two ways. First, most of the transitional forms in vertebrate evolution aren't missing, but in fact have been conclusively identified in the fossil record. Second, it's impossible to pick out a single, definitive "missing link" from the broad continuum of evolution; for example, first there were theropod dinosaurs, then a large array of bird-like theropods, and only then what we consider true birds. With that said, here are 10 so-called missing links that help fill in the story of vertebrate evolution.
1. The Vertebrate Missing Link - Pikaia
One of the most important events in the history of life was when vertebrates--animals with protected nerve cords running down the lengths of their backs--evolved from their invertebrate ancestors. The tiny, translucent, 500-million-year-old Pikaia possessed some crucial vertebrate characteristics: not only that essential spinal cord, but also bilateral symmetry, V-shaped muscles, and a head distinct from its tail, complete with forward-facing eyes. (Two other proto-fish of the Cambrian period, Haikouichthys and Myllokunmingia, also deserve "missing link" status, but Pikaia is the best-known representative of this group.)
2. The Tetrapod Missing Link - Tiktaalik - see above
The 375-million-year-old Tiktaalik is what some paleontologists call a "fishapod," a transitional form perched midway between the prehistoric fish that preceded it and the first true tetrapods of the late Devonian period. Tiktaalik spent most, if not all, of its life in the water, but it boasted a wrist-like structure under its front fins, a flexible neck and primitive lungs, which may have allowed it to climb occasionally onto semi-dry land. Essentially, Tiktaalik blazed the prehistoric trail for its better-known tetrapod descendant of 10 million years later, Acanthostega.
3. The Amphibian Missing Link - Eucritta
Not one of the better-known transitional forms in the fossil record, the full name of this "missing link"--Eucritta melanolimnetes--underlines its special status; it's Greek for "creature from the black lagoon." Eucritta, which lived about 350 million years ago, possessed a weird blend of tetrapod-like, amphibian-like and reptile-like characteristics, especially with regard to its head, eyes and palate. No one has yet identified what the direct successor of Eucritta was, though whatever the identity of this genuine missing link, it probably counted as one of the first true amphibians.
4. The Reptile Missing Link - Hylonomus
About 320 million years ago, give or take a few million years, a population of prehistoric amphibians evolved into the first true reptiles--which, of course, themselves went on to spawn a mighty race of dinosaurs, crocodiles, pterosaurs and sleek, marine predators. To date, the North American Hylonomus is the best candidate for the first true reptile on earth, a tiny (about one foot long and one pound), skittering, insect-eating critter that laid its eggs on dry land rather than in the water. (The relative harmlessness of Hylonomus is best summed up by its name, Greek for "forest mouse.").
...
9. The Mammal Missing Link - Megazostrodon
More so than with other such evolutionary transitions, it's difficult to pinpoint the exact moment when the most advanced therapsids, or "mammal-like reptiles," spawned the first true mammals--since the mouse-sized furballs of the late Triassic period are represented mainly by fossilized teeth! Even still, the African Megazostrodon is as good a candidate as any for a missing link: this tiny creature didn't possess a true mammalian placenta, but it still seems to have suckled its young after they hatched, a level of parental care that put it well toward the mammalian end of the evolutionary spectrum.
10. The Bird Missing Link - Archaeopteryx
Not only does Archaeopteryx count as "a" missing link, but for many years in the 19th century it was "the" missing link, since its spectacularly preserved fossils were discovered only two years after Charles Darwin published On the Origin of Species. Even today, paleontologists disagree about whether Archaeopteryx was mostly dinosaur or mostly bird, or whether it represented a "dead end" in evolution (it's possible that prehistoric birds evolved more than once during the Mesozoic Era, and that modern birds descend from the small, feathered dinosaurs of the late Cretaceous period rather than the Jurassic Archaeopteryx).
So that should suffice to debunk this myth of missing links - they're all out there and abound - and they can all be googled individually.
Originally Posted by Creationist article, Morris
Other gaps are abundant, with no real transitional series anywhere. A very bitter opponent of creation science, paleontologist, Niles Eldredge, has acknowledged that there is little, if any, evidence of evolutionary transitions in the fossil record. Instead, things remain the same!
It is a simple ineluctable truth that virtually all members of a biota remain basically stable, with minor fluctuations, throughout their durations. . . .
Ah - but there's nothing wrong with what he says, even if it's misleading to quote this snippet and then cut him off midsentence! I'm sure it would be interesting, what the content of the ". . . ." section is. Besides that - I checked my dictionary for "virtually" to be sure, it means "almost" and not "entirely". And I've also checked "biota":
Originally Posted by Wikipedia
Biota are the total collection of organisms of a geographic region or a time period, from local geographic scales and instantaneous temporal scales all the way up to whole-planet and whole-timescale spatiotemporal scales. The biota, or biotic component of the Earth make up the biosphere.
So it's important to know, what he actually meant. The way he put it, these biota have a "duration" - so I guess, he meant the term spatially, but it doesn't matter - what he said goes perfectly well with evolution. In stable conditions almost all critters in a geographic region/timescale will remain basically the same over the duration of this environment's stability. Changes up to actual speciation happen, when the environment changes, just as I said. And if it stays stable - nothing much happens, "almost" nothing. I hope you can see how bringing along this crippled quote, not even bothering to quote the sentence as a whole, looks really weak from Morris. He wants to sell this mangled citation as a leading biologist disagreeing with evolution, which obviously it is not.
Edit: I found a better source, an excellent source on watchability of "macroevolution": Observed Instances of Speciation
Please look into that - if you are really out for sampling all that you can find and then making your very own critical mind up on it - this might just be the ticket. It has hundreds of direct sources, too.
*Well - I guess it would have to be unreasonably many thousands of years for the island to be free civilisation's tamperings for such a drastic change to come about. It was just for the sake of example and not a good one, but take non-dogs and good is. Heck - take finches!! How come all of these many supposedly initially different species of finch who supposedly flew to the Galapagos in parallel, weren't found anywhere else? Where had they conspired to invade the Galapagos from? Either every last one of them flew there - or the "remaining" ones must have all self-destructed. Hm...
But best you tell me, what sort of evidence you would consider valid? Give me a better example, if you don't like my vegetarian island dogs!
Tip - check the link above, the underlined one!
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