Evolution - is it real?
Discussion
simonrockman said:
There is an article in the New Scientist Christmas issue asking why evolution hasn't happened in certain ways: No flying plants, it's never created the wheel and no vegetarian snakes (even though there are some non-meat-eating lizards).
While there are no wheels there are organisms that have evolved rotary locomotion and drive methods.https://en.wikipedia.org/wiki/Rotating_locomotion_...
Toltec said:
simonrockman said:
There is an article in the New Scientist Christmas issue asking why evolution hasn't happened in certain ways: No flying plants, it's never created the wheel and no vegetarian snakes (even though there are some non-meat-eating lizards).
While there are no wheels there are organisms that have evolved rotary locomotion and drive methods.https://en.wikipedia.org/wiki/Rotating_locomotion_...
There was an interesting concept in one of Philip Pullman's books. An animal that lived on a planet where volcanic activity had produced long smooth trails of rock. There were also trees that produced huge disc shaped seed containers. So the animals grabbed the discs and used them as wheels until the discs split and released the seeds. Pullman obviously tried to come up with a wheeled animal just for the challenge.
Dr Jekyll said:
There was an interesting concept in one of Philip Pullman's books. An animal that lived on a planet where volcanic activity had produced long smooth trails of rock. There were also trees that produced huge disc shaped seed containers. So the animals grabbed the discs and used them as wheels until the discs split and released the seeds. Pullman obviously tried to come up with a wheeled animal just for the challenge.
Yes, I recall that. The problem with animals evolving wheels is not the lack of roads, as I'm sure there's places on Earth, like the Steppes of Russia, the savannahs of Africa, etc, where wheels might be an improvement. It's the fact that all parts of any animal's body needs a blood supply, arteries, veins and capillaries, and it's hard to see how you could run a blood supply to a wheel, that rotated. They would have to evolve a blood supply that would connect when stationary, and then disconnect when in motion, to allow the wheel to spin freely. 67Dino said:
TwigtheWonderkid said:
67Dino said:
For example, if you accept evolution occurs then you have to accept all living things look like they do by chance rather than design,
It's not really chance. Chance or accident isn't the best way of describing evolution. It isn't chance that the water in the puddle is exactly the same shape as the dip it sits in. The water has moulded itself to fit the available space. Evolution is a process that has driven different plants and animals to fit their particular niche. So it isn't chance that a specific species of bee fits perfectly into a particular type of flower that's unique to where that bee lives. Interestingly, where chance does of course play a key part is in the individual mutations that underly natural selection. But that wasn’t what I meant the first time. I’m just saying that to claw back a modicum of self esteem.
TwigtheWonderkid said:
Yes, I recall that. The problem with animals evolving wheels is not the lack of roads, as I'm sure there's places on Earth, like the Steppes of Russia, the savannahs of Africa, etc, where wheels might be an improvement. It's the fact that all parts of any animal's body needs a blood supply, arteries, veins and capillaries, and it's hard to see how you could run a blood supply to a wheel, that rotated. They would have to evolve a blood supply that would connect when stationary, and then disconnect when in motion, to allow the wheel to spin freely.
Perhaps a wheel could have an independent blood supply and circulatory system. Not in principle totally unworkable, but probably not really evolvable. Dr Jekyll said:
TwigtheWonderkid said:
Yes, I recall that. The problem with animals evolving wheels is not the lack of roads, as I'm sure there's places on Earth, like the Steppes of Russia, the savannahs of Africa, etc, where wheels might be an improvement. It's the fact that all parts of any animal's body needs a blood supply, arteries, veins and capillaries, and it's hard to see how you could run a blood supply to a wheel, that rotated. They would have to evolve a blood supply that would connect when stationary, and then disconnect when in motion, to allow the wheel to spin freely.
Perhaps a wheel could have an independent blood supply and circulatory system. Not in principle totally unworkable, but probably not really evolvable. Einion Yrth said:
Dr Jekyll said:
TwigtheWonderkid said:
Yes, I recall that. The problem with animals evolving wheels is not the lack of roads, as I'm sure there's places on Earth, like the Steppes of Russia, the savannahs of Africa, etc, where wheels might be an improvement. It's the fact that all parts of any animal's body needs a blood supply, arteries, veins and capillaries, and it's hard to see how you could run a blood supply to a wheel, that rotated. They would have to evolve a blood supply that would connect when stationary, and then disconnect when in motion, to allow the wheel to spin freely.
Perhaps a wheel could have an independent blood supply and circulatory system. Not in principle totally unworkable, but probably not really evolvable. TwigtheWonderkid said:
Indeed. To be fully independent from the rest of the body, it would need it's own energy source, so each wheel would need a mouth and a means of waste disposal, and some kind of senses to locate the food, a noise, ears or eyes. It all seems a bit of a faff, and legs or wings appear to be a neater solution.
It's a shame it never happened. It would have been entertaining if nothing else. 
paulguitar said:
TwigtheWonderkid said:
Indeed. To be fully independent from the rest of the body, it would need it's own energy source, so each wheel would need a mouth and a means of waste disposal, and some kind of senses to locate the food, a noise, ears or eyes. It all seems a bit of a faff, and legs or wings appear to be a neater solution.
It's a shame it never happened. It would have been entertaining if nothing else. 
. Snakes that make some attempt to glide from tree to tree? What's that about? Fish where the males embed themselves into the females to form a permanent breeding pair? Weird...TwigtheWonderkid said:
Yes, I get what you mean, and I agree, as we are both backing the same dog in this fight. Although just to be contrary, I would point out that animals with 4 legs, floppy ears and that go woof are largely the product of unnatural selection, i.e they have only exist due to selective breeding by humans. I'm no expert of canine evolution, but I think if you go back just a very short time in evolutionary terms, say 15k years, all we had was wolves. Then a couple of unusually tame wolves were adopted by humans and that bred even tamer wolves, and we were off and running. Now we have chihuahuas and great danes, as a result of selective breeding.
I think it is all selection, some forced, some not forced. I was reading something about Wolves today, can’t remember where. The proposition was that early meat eating man couldn’t actually use all the protein in the meat, so lots of a kill was usually wasted. Wolves realised that there was a source of food near those funny two legged things, and those wolves that were able to interact with humans had a selective advantage - they got fed. Thus there was enormous pressure to hang around humans, hence we got dogs. With modern dog breeding, breeders are doing the selection, but it is the same process.As humans, we have stopped the selection process - for example we allow narrow hipped women to breed with large men, and they don’t die in childbirth. If for some reason we stopped intervening, evolution would happen really quite fast. Say the background radiation levels on the planet increased markedly. How many generations would it take for a human with a somewhat better cell repair process to become dominant? 5 or 10 generations? That’s a blink of an eye in evolutionary terms.
Eric Mc said:
simonrockman said:
There is an article in the New Scientist Christmas issue asking why evolution hasn't happened in certain ways: No flying plants, it's never created the wheel and no vegetarian snakes (even though there are some non-meat-eating lizards).
Many plants make use of airborne transport.
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