Discussion of everything related to the Theory of Evolution.
7 posts • Page 1 of 1
I am having a hard time answering this question for school:
Do biologists cite changes other than mutation that would account for one-celled animals changing to mammals?
Accumulation of desirable genes reaches a limit, right? So, the effect of selection is much too limited to account for the origin of mammals. . .
Thoughts on this are appreciated!
Accumulation of genes is a process that can extend ad infinitum as long as there is a constant supply of new mutations and genetic variation for natural selection to act upon. That said, there are some theories such as the emerging field of epigenetics that seem to suggest that inherited traits may not be solely linked to genes as once thought. Also, in organisms with more complex social structures, learned behavior can play as big as or a bigger role than genetically programmed instinct.
#2 Total Post Count
Again we have emerging theories which proves my point that molecules to man evolution is a theory--not scientific law. It can not be tested as mechanical science theories can, because it is historical science. And yes Alex, hardly anything in science can be 100% for sure, which is all the more reason why we should not be forcing it down our kids throats as though it is fact. "Fact" is not even a step in the scientific method--"scientific law" is.
To "prove" evolution, existing research and evidence is merely fit into the overall models (which are by consensus involuntarily voted as fact) given by modern day evolutionary scientists. If they do not fit new hypotheses will be produced to fit it in. The mentality appears to be, "because evolution happened then I have liberty to form theories about how it took place and how to define existing evidence." This is circular reasoning.
To say that upward mutations can continue forever goes against existing research. The genetic material is designed to copy itself and to produce proteins through the mRNA and tRNA process in the cell. This in turn produces the miracle of the body. To observe this process alone and to say this is a result of continuous, chance, unguided, upward mutations and then NS and speciation is foolish. There are no information adding mutations which are evolving mankind. In fact we see the contrary in down's syndrome and sickle cell anemia, as well as other genetic disorders.
If your going to say that the genetic material is similar, therefore it is proof positive that it has been passed down and we can "trace" evolution in the genes--this is also an interpretation of the evidence. This can just as well fit into a common design mentality--and there is indication that these so-called percentages are being skewed by leaving out so-called junk DNA and other areas of sequencing.
Furthermore, the fossil record is nothing but a mark against the theory. Even so called missing links appear with fully formed features. A good example is the fish eusthenopteron
and amphibian ichstyothega, claimed to be transitional forms. One has fully developed fins, one has fully developed legs. Because they have similar features in head and body, and I stress similar, they are suggested to be transitional forms. Let me use an example from principles of design--an amphibious vehicle has features of both a boat and a land vehicle, because it is DESIGNED for both environments. But a boat has no means of land travel because it is DESIGNED for only water. In the same way amphibians are designed for water and land so they must have features that facilitate a watery and a land environment. Fish are generally designed for water so they have features designed for water.
If evolution had happened, the fossil record should be showing the unselected species which died because of weak traits, such as an unusable leg because it is part fin. Again mechanically and logistically IMPRACTICAL and improbable, which is usually the case for evolution.
It comes down to your presuppositions as to how you will fit the evidence. You will always be biased toward your presuppositions, which in turn become convictions. You will always try to fit data into your interpretation of reality. And you will also try to find evidence to justify your position. It is a self fulfilling prophecy. This is why Jesus said, "Be careful how you hear, for with what measure you mete out, it will be met out to you." And Paul said, In the last days men would heap unto themselves teachers, having itching ears. The angel said to Daniel about the end time, Knowledge will be vastly increased and many will travel to and fro.
Perhaps a brief explanation on the scientific definition of "theory" would be helpful. Theories are explanations of natural phenomenon. The value of a theory rises or falls depending on how well it can be tested against observable facts using falsifiable hypotheses. Theories can never become scientific law because in science, laws are completely different things. Simply put, a law (ex: Newton's laws of motion) describes a phenomenon while a theory attempts to explain it. There are, for example, many different theories of gravity attempting to explain the phenomenon of objects falling. Does this mean gravity does not exist, or is not a factual phenomenon?
No, the mentality is, "This is what we observe; how can we explain it?" Not circular reasoning at all; in fact it's sound science.
Junk DNA is a geneticist's best friend when piecing together phylogenetic lineages. Because junk DNA is essentially unused, it has no selective pressure on it. Thus mutations to junk DNA are virtually impossible for natural selection to act upon or weed out. These mutations happen at a mathematically predictable rate (about once every billion replications, if memory serves), and we usually know approximately what the generation time is for the organism being studied. This allows us to take two closely-related species, which almost always have similar junk DNA, and analyze the differences between them. These differences can then be computed along with the known rate of mutations and approximate generation time to estimate how long ago it was that these two species diverged from a common ancestor. It's all rather simple math, when you come down to it.
I'd suggest you read up on Tiktaalik (http://en.wikipedia.org/wiki/Tiktaalik), a species of lobe-finned fish that's about as close to a half-fish/half-amphibian as you can wish for. To claim that the fossil record is inconsistent with current evolutionary theory is worse than inaccurate; fossil lineages display exactly the sort of gradual progression that would be expected from an evolutionary process.
Or maybe it survived in a different environment from what you are considering? Some researchers have speculated that tetrapod limbs originally evolved for movement in water, not land. The environment where tetrapodomorphs lived was sort of like a modern-day mangrove swamp, where movement through water was often restricted by dense tree roots. It's possible that sturdy fins, gradually evolving into primitive legs, would have been more efficient for "climbing" or "crawling" through the tree roots rather than swimming through them. Also consider that perfectly normal fish-fins can be very useful for getting around on land without any modification at all; there are many species of fish that are quite capable of moving across dry land, such as mudskippers and some species of catfish. So the idea that a species adapted to one environment would have to be incapable of surviving in another is quite simply untrue.
If this is true then we should just give up now, because it's going to be impossible to discover anything even vaguely resembling hard fact. In fact, if this is true, then I could perfectly legitimately claim that Copernicus was full of bull, and that the earth really is the center of the universe. I could even go so far as to demand that geocentricism deserves equal merit and must be taught in classrooms alongside heliocentricism. Of course, if we start doing that, we're also going to have to teach children that the earth sits on the back of a giant tortoise, babies are delivered by the stork, and the entire universe was created by the flying spaghetti monster. I'm sure I don't have to explain what a complete mockery of educational decency this would be.
The idea that a person is automatically biased and unable to think outside that bias is about as wrong as you can get. I'll grant you most people are very closed-minded, but a lot of people are perfectly capable of "thinking outside the box" when necessary. Take Galileo for example. He began his academic career teaching his students that the earth is the center of the universe, and continued doing so for a good while after Copernicus began saying that it wasn't. Yet when Galileo took a good hard look at the evidence, he realized that he had been wrong, and began to teach his students that the sun, not the earth, is the center of the solar system. Now, if Galileo had been biased by his "presuppositions," as you insist all people are, he would've gone to his grave still believing the Ptolemaic model of the universe. I'm glad we don't live in a world where everyone is as stiff-necked and closed-minded as you seem to think we are.
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A very small percentage of large animals get fossilized because to fossilize something it has to be separated from the atmosphere so as to eliminate oxidation and other weathering; landslides, ashes from volcanoes are good fossilizing events. An organism with an disadvantageous trait will die and not be able to pass on its genes depending on the severity of the disadvantage, so the possibility of that one mutant being fossilized is very small compared to the healthy gene passing individuals. Common sense.
I think you've pretty much covered it Alex
A wise man once said to me:
"Build a man a fire, and he'll be warm for a day. Set a man on fire, and he'll be warm for the rest of his life."
Only the fittest chickens cross the road.
Wow, Alex, you absolutely rock when it comes to explaining evolution to people who keep ignoring obvious and overwhelming evidence! I wish all creationists read a couple of your posts and they would see in no time how neatly evolution and natural selection work :o
As a side note, does anyone know what is Islam's view of evolution? Do they have similar conservative sects that close their eyes from the evidence and blindly hold on to their age-old beliefs? Man, it's hard to believe that even today certain religious people are so regressive that they essentially hold back scientific progress and try to feed lies to school children, yet it happens all the time. Not only in the area of evolution, but think about, say, stem cell research...
I'm glad that majority of religious people seem to be fairly sensible, but the few conservative ones really worry me, because they aim to brainwash children before they even have learnt to think with their own brains.
Just wanted to add the theory of mitochondria as ancient remanents of a symbiotic bacteria. This theory also extends for chloroplasts in plant cells. These are mutations in a way I guess, but more of an incorporation for the mutual interest of thriving when oxygen was beginning to accumulate in the atmosphere.
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