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Fish with Limbs
kpogoda writes "American scientists have unearthed the world's oldest arm bone, a 365-million-year-old fossil that provides key evidence that fish used limbs in water well before animals used them to climb up on land."
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an aquatic, salamander-like creature that would have pushed its arms downward to move through shallow rivers, and used them to prop itself up while waiting for prey or to get air.
sounds like a fish to me!If you get nervous, just remember that there are a few billion other people who don't really give a damn.
Evolution is NOT planned. It has nothing to do with intention. Suppose we lived in a world with increasingly intense sunlight (for whatever reason), so that the darker and thicker your skin/hair pigmentation, the more you resist exposure in the wild. If you have sensitive light skin, you'll get burns everywhere, which may perhaps develop into cancer. In 1000 years, when sunlight is extremely intense, most of the pale sensitive-skinned people are dead, while most of the dark tough-skinned are alive. Did anyone plan this? No. Did dark skinned people think "hey! I'm gonna start developing darker skin to survive better"? No. But the population has just "evolved" darker and tougher sun-resistant skin, like it or not, because the ones that didn't have it died off. It's as simple as that.
People only talk about evolution as a "shaping force" figuratively. It's in fact nothing but an observation about consequence. It's not some insidious super-power you can will.
OK, I shouldn't, but I'll bite. First, mutation is not the only (or even, necessarily, the most important) source of genetic change. Bear in mind that each individual has unique DNA. Normal variation is enough to drive a certain amount of evolution.
Second, your question about whether living on land is beneficial is incorrectly framed. It's not a question of "benefit". The question is, "Will this mutation give the individual's descendants a reproductive edge, however slight?" In the case of moving into a new ecological niche, the answer might well be, "Yes."
Your next layer of argument (mutation not surviving reproduction) is redundant. You have already eliminated harmful mutations; mutations that impair reproduction are by definition harmful. Nothing to see here except obfuscation; move along.
"The chances keep decreasing"? No, the cumulative effect is INCREASED. We're not talking about the likelihood of specific changes to one descent line; we're talking about changes that propagate laterally through a gene pool over time as new genetic combinations provide a reproductive advantage. The math is quite possible; I wouldn't call yours "impossible", just misapplied.
Finally, by what logic do you assert that the twisted bone or shortened muscle to which you refer does not make the specimen more likely to confer reproductive advantage on its progeny (NOT survival)? Your assertion is groundless and poorly stated. In fact, I can think of several ways this physical change could confer reproductive advantage. Perhaps your imagination is more limited. Regardless, the fossil record is full of species (up to and including our own) that found bone and muscle structures tuned to living on land to be useful.
I'd suggest you read some of Richard Dawkins' excellent writing for a better understanding of how evolution is thought to work. Have a nice day.
Corruptissima re publica plurimae leges.
What if natural selection does not improve the species? What if all living things were created in their best form, and have been heading downhill since then? Natural selection then plays the role not of improving a species, but of slowing its decline - such that if the power of natural selection was absent, the fall of a species would be hurried. Yet if natural selection was present, the species would still degrade, but at a much slower rate.
I have no idea who you are, so I'll try to be as cordial as possible.
You're completely misreading evolution.
Natural Selection doesn't try to DO anything. It's the name for a simple "phenomenon" - anything that survives 'til the opportunity to reproduce has some of it's genetic material passed down to the next generation.
There's no way anyone could construe Natural Selection in the way you're talking about. There's no "absense" of natural selection possible. If nothing survives, then quite simply, everything was "selected against", that is, it couldn't survive in it's current environment and didn't. End of story. If everything survives, then the current environment is safe until 'Time K', which is some time in the future when the Carrying Capacity [i.e., amount of our species the environment can sustain] of said environment has been reached.
Evolution happens, whether or not it's of divine design. Things were not *created*, they *happened*. DNA isn't that big of a coincidence when you consider the practical infinity of time and the practical infinity of the universe.
Your idea that things might have started off as "better" is bogus. The point of evolution is simple: The thing that survives moves on in the form of the gene.
First of all, you do not understand the theory of evolution AND you use "darwinist" in a way that does not reflect its true meaning.
Darwinist is in opposotion to Lamarckist, who was an evolutionary theory from before Darwin that postulated that the evolution of species was the result of adaptation made by members of the species in their life times (to Lamarck, if giraffes had long necks it was because proto-giraffes had had to stretch their necks to get to high branches and so their descendants had longer necks).
Darwin's theory was that natural selection of mutants was what shaped evolution.
If you assume darwinism, then it would be irrational to suppose that one human race is not inferior or superior to another.
Well, that might be what the grand wizard at your "racial pride" rally told you, but that is completly wrong.
If I take an Inuit and a Massai and switch them, they'll both be fucked. Because one is from a race that has adapted to the artic climate and the other to the savannah. Wich is the inferior one? The one that can survive in a cold hostile land or the one that can survive in a hot hostile land?
Races are not inferior or superior in an absolute sense, they are better adapted to specific situations.
If we are all the product of chance, then there is no good or evil.
Ah, yes, you're the type of person for whom the only reason not to hurt other people is the fear of hell.
So clearly, you do not reject darwinist evolution based on rational arguments, but based on irrational fears. Fear of what people would do if they didn't have the fear of hell in them...
To suppose that Darwinism doesn't lead to racism is the ultimate in willful blindness.
You retard. There was racism before Darwin, there was racism before the theory of evolution.
The bible promotes racism. There are the superior tribes, descendants of angels, and the others are inferior. God commanded the israelites to genocide at jehricho.
Stop trying to discredit things you don't like by linking them to things others don't like.
You absolutely, necessarily, have to be racist to be a Darwinist.
You absolutly, necesserily have to be a racist to believe in god, because god is racist.
You cannot have every group survive, because some must fail.
Again, wrong because you do not understand the theory of evolution and the darwinist theory of survival of the fittest.
As long as there are enough ressources, all groups can survive. There is no magic need for one group to diappear.
The point is that there is no good or evil, and that we can't trust the convictions of our mind if we assume Darwinism.
That's nihilism, not darwinism.
And you should never trust the convictions of your mind.
You can't take the sky from me...