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Natural selection is proven wrongModerator: BioTeam You do realize the Cambrian era was quite a few years ago? Did it ever occur to you that maybe, just maybe, we don't know all about the environment and species living that time? Just because it looks more difficult to explain than certain other periods in history doesn't disprove evolution or natural selection.
There are several reasonable explanations for this event that are in line with the theory of evolution. For example, each year there are findings of pre-Cambrian organisms that have been unknown this far and may prove to be the ancestors of those more advanced organisms that allegedly "appeared from nowhere". The whole phenomenon has possibly been a sum of many factors and only because we do not know all of them (yet) hardly gives a reason to doubt natural selection. Actually Wikipedia, which you so eagerly keep quoting, lists many factors that help to explain the Cambrian explosion. Maybe you should look at the whole picture instead of choosing few isolated lines or chapters that seem to support your view when taken out of context.
And the problem with this would be???
Seconded. Generally speaking, the more people talk about "being saved," the further away they actually are from true salvation.
~Alex #2 Total Post Count
Re: Natural selection is proven wrong
read dean
Your entire argument is based on natural selection only being able to work on DNA that is already present in a population, but this is where mutation comes into play for creating new genes for natural selection to work with. Thus you entire argument is like a castle built on sand, doomed to collapse.
Generally speaking, the more people talk about "being saved," the further away they actually are from true salvation.
~Alex #2 Total Post Count
Re: Natural selection is proven wrong
fact is speciation a new species has new genes not present in the antecendent species so they could not have been passed on as NS says -thus you own words show NS is wrong
gamila, let me try to walk you through this. Evolution is based on two principles: descent with modification and natural selection. "Descent with modification" just means that new muations are inherited from parent to offspring. Darwin didn't know the source of modifications, but modern genetics understands it well. New mutations in DNA happen all the time. Errors during the replication of DNA when a cell divides, radiation from a variety of natural and man-made sources, various chemicals in the environment - these can all cause mutations. When they happen in germ cells (sperm and eggs in sexually reproducing organisms, or anywhere in unicellular organisms that reproduce by simply dividing), these new changes are inherited. Now, natural selection. This seems to be where you are having trouble. You say that natural selection only acts on traits that are already present. You are absolutely right. But you must admit that there is variation within species. No two people are the same. Dogs are a good example, too. Look at all the different breeds within a single species. Where did this variation come from? Mutations. One here, one there, one now, one later. They accumulate in populations over time. Long periods of time. This is what natural selection acts on. Some individual or combinations of variations help an organism to survive and reproduce. Some don't. Most are pretty neutral. Nature selects those that help, and weeds out those that don't - perhaps not quickly, but statistically over time, this is what happens. New species don't arise overnight. Imagine a species that has a large range where environmental conditions vary (including purely physical conditions such as climate, and nonphysical conditions such as the community of other species present). A population of that species in the eastern part of that range lives in an environment that is somewhat different than what a population in the western part of the range lives in. "Nature" is different in the east and the west. Natural selection will therefore select for different traits in the two populations that are already present in the species. These two populations will therefore become somewhat different over time. If the flow of genetic material (sex) between these populations is somehow prevented, the two populations will continue to diverge genetically to the point where if they were to meet again, their genomes are sufficiently different that they can no longer interbreed. By our definition, they are different species. Voila.
Now, the Cambrian explosion. This "explosion" occurred over a period of 40-50 million years. It's called an explosion because relative to other geological eras, a lot of new forms did indeed appear. If you look at the fossils from one site, e.g. the Burgess shales, you do see forms appearing "suddenly" without evidence of intermediate forms in lower strata at the same site. This is probably because conditions at that site were not conducive to the preservation of fossils in the lower strata. You must try to understand how fossils are formed. Not every organism that dies gets fossilized. You need an environment where sediments can cover a dead organism (quickly) and conditions that will prevent its complete destruction once buried. This doesn't happen everywhere at all times. The fossil record is very spotty indeed. Dead organsims only get fossilized here and there, now and then. And we certainly haven't looked everywhere on this planet. The search for intermediate forms is very slowly finding a number of "missing links". People used to claim that the gaps in the fossil record between reptiles and mammals, reptiles and birds, apes and humans, etc., etc. were evidence against evolution. These gaps, though, are slowly being filled by new discoveries. We've only been at this fossil-hunting game for a very, very short time. More and more fossils from the Cambrian are being found from periods earlier than those where many new forms "suddenly" appeared. But nowhere (yet) has anyone found a single site representing the entire Cambrian that might contain all early, intermediate, and later forms. So please have patience, and an open mind.
Re: Natural selection is proven wrong
i am not talking about variations in a species but complete new species with complete new genes the new species differs from the older species because it has new genes-never before seen thus NS can account for it as it only deals with genes already present http://conservativecolloquium.wordpress ... evolution/
Re: Natural selection is proven wrongbefore you can talk about speciation you have to know what a species is
and there is no agreement so you cannot argue as you all do that speciation does not make NS wrong- untill there is a definition
http://www.pubmedcentral.nih.gov/articl ... rtid=22088
http://en.wikipedia.org/wiki/Species
now purely from the NS formulation speciation shows it to be wrong ie NS is about genes already present being passed on as such it cant account for a completely new species-with new genes never seen before http://conservativecolloquium.wordpress ... evolution/
And where do you think these new genes came from? Mutations! I find it interesting that you dropped your argument about cancer almost as quickly as that was explained to you. In fact you still haven't answered my question as to what (if anything) you found wrong with my analysis. Have you conceded this point or are you simply neglecting to answer it? For that matter, you also haven't presented any legitimate scientific sources to verify your claims. As much as I love wikipedia, it doesn't even come close to counting as a scientific source. Another question I would like to ask is what theory you wish to propose in place of natural selection, and what evidence you can put forward for it. Generally speaking, the more people talk about "being saved," the further away they actually are from true salvation.
~Alex #2 Total Post Count
Re: Natural selection is proven wrong
what is this
Re: Natural selection is proven wrong
It's an ABC News article, written for a popular audience, that just happens to have absolutely nothing at all to do with natural selection.. By "legitimate scientific source," I was thinking more along the lines of a peer-reviewed journal that is actually relevant to the topic of our discussion. Nature would be a good place to start, but there are plenty of others. Heck, I'd even settle for an article from Scientific American or National Geographic at this point. Even if they're not peer-reviewed journals, they at least usually make an effort to ensure that their articles bear some resemblance to verifiable facts. Generally speaking, the more people talk about "being saved," the further away they actually are from true salvation.
~Alex #2 Total Post Count
Re: Natural selection is proven wrong
if you followed the link you will see it is legitamate http://www.abc.net.au/science/articles/ ... 529713.htm
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