Calling all evolutionists!------Limbs for flight
I would like to read the arguments of daring evolutionists who think they can explain how the genes of life incrementally evolved a species that could utilize the principles of flight.
Did the gene pool understand the principles of flight and thus evolved a set of wings for the utility of flight? How was flight a known possibility? The concept of flight?
(Pardon the awkwardness of the question. No insult is intended. If you have a more suitable question of the subject submit it, and I’ll post it if I agree.)
Serious replies only!
Chance
Side Score: 16
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Experiment
Side Score: 9
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Excellent question! I've always been fascinated by how birds came to "learn" how to fly over time. Keep in mind that evolution does not occur over a few generations or in one lifetime, but that it takes millions of years. Well feathers are basically mutated scales and derived from the scales of reptiles (dinosaurs specifically). Feathers helped in flight because they were able to keep the warm blooded dinosaurs who had them at a constant temperature, like humans and mammals do with fur. Feathers were also hollow on the inside, just like many of birds' bones, which helped birds stay in flight without succumbing to gravity. But how did flight some to be? Flight did not miraculously happen over night, mind you. Some species of dinosaur lived in trees and had the ability to climb up the bark and onto limbs. But what if they were being chased by something else that could climb a tree too? This is where they had the advantage. Predecessors to birds were able to jump from the branch of a tree and "float" to the safety of another tree nearby. The same can be seen in flying squirrels. Eventually, the species evolved bodies that were more aerodynamic and soon enough, they were able to leap from a branch and stay in flight. The next step was the easiest- lift of from the ground with massive wings and flight into the horizon. If you want to know more, research the Archaeopteryx, which is the common ancestor of all birds, I believe. Side: Chance
Thanks for the information. You are the first brave soul to attempt an answer; will you also be the last brave soul? I have a couple questions concerning Archaeopteryx lithographica. Can we know with any degree of certainty that A.L. is a bird of flight and thus its feathers enabled flight? Does the fossil record contain transitional fossils that evidence the origin of Archaeopteryx lithographica? You have provided a summarized explanation of the evolution for flight of a species of bird; would you also do the same for flying insects? I appreciate your input. I will not attempt to drag you out on a limb in a debate, so feel free to share your evidence and opinion. Side: moderator
Evolution doesn't have a goal, or a purpose. It simply is. That's what I think is so scary for some Christians who don't quite like being left out on a limb like that. Flight wasn't engineered. It just happened. A creature, while procreating, gave birth to another creature who experienced a mutation. (I don't know if you know what a mutation is, I've met some Christians who don't. So for the purpose of being clear I will explain that a mutation is not a bad thing. It is simply a random change in the genetic code that changes a physiological feature of an individual). These mutations either aid or hinder an individual's chance at procreating. Fitness, to anthropologists, is not how physically fit you are, but the amount of offspring you produced. The survival of the fittest means that a species who procreates the most will survive. So if a mutation makes you fitter (more able to produce offspring) then your genes are passed on. So lets relate what we learned back to flight. Flight happened in birds, because it is a physiological feature that made them more fit (better able to produce offspring). It helped them fill a niche, where they can thrive. A Christian boy once told me that the trees are green because green is a soothing color and God wanted us to be soothed in nature... I believe that is your basic mentality and while it is pleasant to know that there is something out there that wants us to be soothed... you have to try and peel away from those mentalities and put your feet back on earth. Side: Chance
Well I didn't read anywhere that Achaeopteryx was a legitimate bird of flight, but if I had to guess, I'd say it glided and did not fly. This is because fossil records show it had teeth, which were heavy and were not conducive to flight. Although it did have hollow bones, great for flying, this does not mean the bird was capable of flight. And feathers were not anything new either- some species of dinosaur used feathers as a way to control their body temperatures in the form of insulation. Believe it or not, Velociraptors actually had feathers as well as scales (although Hollywood corrupted their anatomy in Jurassic Park and left out the feathers). Insect flight is difficult to explain because scientists do not have enough information to formally express the origins of the insect wing. It is believed that dragonflies were the first flying insects in the world because of their primitive structure. They have two sets of wings and are unable to fold them over their bodies, like a house fly would do today. Many hypothesize that their flight derived from the "wings" of insects that used them to sail over water, like the common stonefly. However, nothing can be finalized as of yet. Side: Chance
I'm not quite sure what "Chance" and "Experiment" are supposed to mean. I'm just posting this wherever it lands, by chance. So to speak. I'll skip any description of the mechanics of evolution. There's plenty on that elsewhere. I see it this way: 1. Flightless animals who move by hopping, like birds still do with their feet.
2. The use of limbs to increase momentum in the jump, for greater distance. 3. Skin flaps that catch the air and allow the animal to soar a bit. 4. Specialized limbs, once flight efficacy outweighs the amazing adaptation of stubby dino-arms too short to scratch one's own balls. Now how about the eyeball? That's the one anti-evolutionists always pull out; anyone know of a viable progression like the one above for how they might have evolved? Side: Chance
Yeah, I hear "the eye is so complex, gee wiz" strawman argument a lot, probably because Darwin himself used it as a self-admited example of why some might find his theory hard to believe. It's not so far fetched: http://en.wikipedia.org/wiki/Evolution_of_the_eye http://www.abarnett.demon.co.uk/atheism/ Side: Chance
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I do not believe that gene pool can "believe" that wings can make things fly, in constrast, I believe that it is through the famous natural selection process that this is done, hence it may be called experimentation(on nature). As we all know, fossils have shown us the "missing link" between the flying and the non-flying animals, such as the archaeopteryx and some other flying reptiles. If you have noticed, throughout the mesozoic era, flying reptiles such as the pterosaurs do not really have wings, but simply stretches of skins below their skinny arms. This proves that mechanics flight built into biology is definitely not chance dependant. Only when these "skin-winged" animals have appeared a long time, then those with real wings and feathers start showing up, depicting the selection by nature of the more efficient in flight. Side: Experiment
The choosen sides are not ideal, since they're not mutually exclusive. Evolution includes both chance and experiment. I'd imagine the process started off with animals that could glide, favoring the lighter animals with broader "wings" until true flight was accomplished. Side: Experiment
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