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Evolution Transforms "Junk" DNA into Genetic Machinery HealthNewsDigest.com) - Evolution has mastered the art of turning trash to treasure - though, for scientists, witnessing the transformation can require a bit of patience. In new genetic research, scientists have traced the 170 million-year evolution of a piece of ?junk? DNA to its modern incarnation as an important regulator of energy balance in mammals. If the "junk" to "modern incarnation" is random or selected by a process which is opportunistic then is it not possible that "modern incarnation " becomes "junk" tomorrow..Where is the proof that DNA carries "junk"?The discovery, they said, suggests that regions of the genome formerly presumed to be a genetic junkyard may actually be a hardware superstore, providing components that can be used to evolve new genes or new species. Who is providing to whom??We thought we had found the tip of the iceberg of an evolutionary process that started around 200 million years ago, and we got really fascinated by the idea of pulling up the entire iceberg from the depths.?Marcelo Rubinstein The discoveries were reported by Howard Hughes Medical Institute international research scholar Marcelo Rubinstein and his colleagues October 5, 2007, in the online PLoS Genetics. Rubinstein is at the Institute for Research on Genetic Engineering and Molecular Biology of the National Council for Science and Technology in Argentina, and the University of Buenos Aires. Researchers have long known that all genomes are prodigiously sprinkled with DNA fragments derived from mobile elements that have jumped to apparently random points in the genome. For example, the Human Genome Project revealed that about 45 percent of our genome consists of mobile element-derived sequences. Is it a random process or there is some natural selection?Confusing both . GENOMES are randomly sprinkled with DNA fragments????The classical view has considered genomic sequences derived from mobile elements as ?junk? DNA?a large accumulation of useless sequences,? said Rubinstein. ?However, more recent work, including the findings in this paper, is producing convincing evidence that these sequences provided raw material for the evolution of novel gene functions.? How? And Who provided ? Rubinstein and his colleagues had been studying one such piece of DNA, called nPE2, which enhances the activity of a gene called POMC (proopiomelanocortin). The POMC gene is expressed in cells in the brain and produces peptides that regulate a variety of behaviors, including food intake and stress-induced analgesia. ?Our studies showed that nPE2 is highly conserved in mammals but absent in other vertebrates, so we became interested in studying its evolutionary origins,? said Rubinstein. ?We then found nPE2 to be highly similar to sequences present in the genomes of the marsupials opossum and wallaby. So we thought we had found the tip of the iceberg of an evolutionary process that started around 200 million years ago, and we got really fascinated by the idea of pulling up the entire iceberg from the depths.? In fact, Rubinstein and his colleagues realized that all similar sequences originated from a superfamily of mobile elements called CORE-short interspersed elements (CORE-SINES). CORE-SINES are retroposons, meaning the genetic sequence has been copied before being inserted into new sites in the genome. To reveal more of nPE2's evolutionary history, the researchers compared nPE2 sequences from 16 mammalian species, including human, dog, mouse, and rabbit. They found the nPE2 enhancer sequence to be highly conserved. By creating altered versions of the nPE2 sequence and testing their ability to enhance gene expression in transgenic mice, they showed that the regions that were critical to nPE2's function were most rigorously conserved over evolution. The findings, Rubinstein said, indicated that nPE2's function ?contributed to the fitness of all mammals, A collection of gene contributes to the fitness and not a single gene or behaviour.probably by better tuning the central regulation of energy balance.? ?This paper shows, for the first time, that a retroposon of this superfamily got inserted near the POMC gene sometime before 170 million years ago; and after suffering a limited number of random mutations, it acquired a novel and useful function and became fixed in the genome of an ancestor to all mammals,? said Rubinstein. here it is clearly written that the mutations are random.For a random cause anything can happen tomorrow a gentic disease can appear for random cause?!The findings provide clear evidence that genes use a collection of functional sequences incorporated at different times during a very long-lasting evolutionary process, said Rubinstein. ?Novel sequences that improved fitness got fixed into the genomes and continued to travel to the future together with more ancient functional sequences,? he said. How long does it take to fix the definition of fitness? Life is not a computer program!!The researchers found a large number of other CORE-SINE superfamily members that had changed very little over evolutionary time, suggesting that nPE2's evolution from junk to regulatory DNA was not a unique event. contradicting random nature of mutations...how is it possible that some memebers underwent random mutations some did not...we are talking about a timescale == eternity.In fact, Rubinstein suspects that thousands of currently functional elements are derived from ancient retroposon insertions?but their evolutionary history still needs to be untangled. ?We are starting to understand how insertional elements, instead of being useless or harmful for the genomes, may be beneficial.?
Putty-nosed monkeys, Cercopithecus nictitans stampflii, occur at various sites in West Africa, particularly in the transition zone between rainforest and savannah. The species is sometimes seen in primary rainforest, although at a curiously low density compared with that of other monkey species. We conducted a 24-month field study in the tropical rainforest of Taï National Park, Ivory Coast, and found that putty-nosed monkeys require an ecological niche almost identical to that of the Diana monkeys, Cercopithecus diana diana. Moreover, the niche breadth of putty-nosed monkeys was significantly decreased in the presence of Diana monkeys, suggesting that feeding competition with Diana monkeys kept putty-nosed monkeys from successfully colonizing a rainforest habitat. However, contrary to the interspecies competition hypothesis, groups of both species almost completely overlapped in home ranges and formed near-permanent mixed-species associations, rather than avoiding each other. We hypothesized that Diana monkeys tolerated immigrating putty-nosed monkeys and formed mixed-species groups with them, despite high levels of competition, because of their merit in predation defense. Direct observations and a series of field experiments confirmed that male putty-nosed monkeys play a vital role in defense against crowned eagles, suggesting that putty-nosed monkeys obtain access to feeding trees by offering antipredation benefits to Diana monkeys. We discuss these findings in light of biological market theory.
The quote you have put in there explains that cooperating is of genetic benefit to both species - one gets access to food while the other gets extra protection from predators.So neither/both are the 'favourable gene carrier'. They aren't competing because they both gain from not doing so.
This strategy has nothing to do with pleasure, it's a result of natural selection.
Natural selection is the process by which favorable traits that are heritable become more common in successive generations of a population of reproducing organisms, and unfavorable traits that are heritable become less common. Natural selection acts on the phenotype, or the observable characteristics of an organism, such that individuals with favorable phenotypes are more likely to survive and reproduce than those with less favorable phenotypes. If these phenotypes have a genetic basis, then the genotype associated with the favorable phenotype will increase in frequency in the next generation. Over time, this process can result in adaptations that specialize organisms for particular ecological niches and may eventually result in the emergence of new species.
Hence the explanation is absurd and contradictory.
It is a norm to discuss in terms of benefits of cooperation towards survival but we cant ask why?
Can I say that cooperation leads towards favourable gene ? No . Hence such a argument is merely an observation based on opportunistic survival of species and it is not an explanation grounded in the mechanics of evolution using genetic replication.
It is strategy towards sustainable pleasure.. as you said one provides extra protection and other food.
I comment to educate the people about logic.So many mathematicians went mad doing logic and it should not be taken lightly.
Natural selection is the process by which favorable traits that are heritable become more common in successive generations of a population of reproducing organisms, and unfavorable traits that are heritable become less common.
Natural selection acts on the phenotype, or the observable characteristics of an organism, such that individuals with favorable phenotypes are more likely to survive and reproduce than those with less favorable phenotypes. If these phenotypes have a genetic basis, then the genotype associated with the favorable phenotype will increase in frequency in the next generation. Over time, this process can result in adaptations that specialize organisms for particular ecological niches and may eventually result in the emergence of new species.
Chicken Moth argument is insane.
Moth doesnt evolve for the predators... Whereas Chicken evolves for us....Do I need to say more?
Such statements misleads science and people in general.
To be honest, I dont really understand what you're getting at.
QuoteChicken Moth argument is insane.Who mentioned chicken moths?
QuoteMoth doesnt evolve for the predators... Whereas Chicken evolves for us....Do I need to say more?Yes, you do. You need to explain why you dont understand the very simple premise that the selection pressures operating on the moth are completely different to those operating on the chicken. I will try to explain again, but it seems that you aren't paying any attention, or are just refusing to understand.Well camouflaged moths are more likely to survive to breeding age than poorly camouflaged moths, so more of the next generation will have 'well camouflaged' genes. The selection pressure therefore means that the proportion of the 'dark' gene in the population will increase.In chickens, the selection pressure is artificial. Chicken breeders choose which traits they want to continue into the next generation. the selection pressure is towards fat chickens & high egg production, not towards the traits that would assist a chicken to live in the wild. Given these artificially selective pressures, the proportion of the 'good farming' genes will increase.
You are wrong, and seem unwilling to admit it. I do not appreciate the fact that I took my time to explain to you the mechanics of artificial selection and natural selection, only for you to call it insane.
QuoteSuch statements misleads science and people in general.I do hope you're not referring to anything I have said here, as that would practically be slander.I hope you will behave like a reasonable human being, do some research with an open mind prior to commenting on anything I have said. Evolution by natural selection of heritable traits is the best theory we have to fit the data we have collected, and can make accurate predictions. The TSP idea of yours is ridiculous, and is of no scientific merit.This forum will open it's arms to you and you can enjoy discussing science with the great many people here, but you need to open your mind to ideas other than your own, and maybe eventually people will start listening to what you have to say.
We are eating the healthy ones and breeding none.
For chickens apparently there is no choice.
Oh, I see, you think that to call a selection pressure put in place by people 'artificial' is to anthropomorphise. Fair enough. But it remains that the selective pressures on chickens have shaped their evolution to become what we think of today as farm chickens.
QuoteWe are eating the healthy ones and breeding none.Nonsense. We chose the best ones to breed, so that we will have the best next generation of chickens for us to farm. This again points out that you do not have the faintest clue what you are talking about.QuoteFor chickens apparently there is no choice.There is no choice for moths. They are born a certain colour, and will either survive to breed or won't. There is no 'predator impulse' - in a predated population, the genes which offer an advantage are more likely to survive to breed. That's it.
What is the difference between Chicken evolution and the Moth evolution ? Chance.
If this is the case then no meaning can be attached to Natural selection. It is a purely random process. There is no selection involved.
DKV, I'm going to have one last try at explaining this to you, and if you continue to refuse to listen then I will give up and, like Stefan, ask you to read up about the subject before posting again.
Maybe moths and chickens are too close to your heart, so I will use an extra set of examples.You seem to grasp that with the peppered moth, random mutations offered an advantage to specific individuals, who were then more likely to breed (as they were less likely to be predated) and so the proportion of these mutations was higher in the following generation. Assuming these still offered an advantage, this process would be repeated and the next generation would also have a higher proportion of these mutations and so onYou don't, however, seem to understand that with chickens it's not those that get eaten that are important, but those that we choose to breed. One cockerel has a mutation that makes his offspring produce more eggs - so we breed him with others. His offspring also carry this mutation, so we breed them with others. We are selecting the traits that we want. We do not allow free mating in the chicken population, we decide which chickens will breed - so the mutations that become more common in the future generations are not ones for survivability, as they are in the moths, but the ones for traits that we find desirable.
you think that to call a selection pressure put in place by people 'artificial' is to anthropomorphise.Fair enough.
QuoteWhat is the difference between Chicken evolution and the Moth evolution ? Chance.Do you now see that this is completely wrong? The difference is the selection pressure - in moths a pressure applied by their predators that results in better camouflaged ones surviving to breed, in chickens a pressure applied by us hat results in fatter chickens/chickens that produce more eggs being bred.
Okay, a new example to try and help you get over the intellectual problems you are having with chickens and moths...A wolf living in the wild - any adaptation that helps a wolf survive, (be they better able to hunt, withstand hunger, cope with a wider range of temperatures) will make that wolf more likely to survive long enough to breed. This means that these adaptations will be better represented in the future wolf population. So the pressures of it's environment act to select the mutations that offer an advantage to the organism.Okay so far?
A huskie living in a community that relies on dog sleds - The sled owners will carefully chose which male dog to mate with their bitches. They will not chose the dog with the best instincts/abilities for survival, they will pick the best runner or the one with the best endurance running skills. This way, the mutations that improve ability to hunt are not selected, and do not increase in proportion in the future generation, but the mutations that improve speed and endurance will be selected, and will increase in proportion in the next generation.How're you doing?
Quote Pet Dog breeding - take, for example, a poodle. A poodle with best adaptation to survive in the wild may not have the traits that poodle breeders want. Nor would a poodle who could run fastest, pull the heaviest load or run for longest. Poodle breeders are looking for the most handsome dog, the nicest, glossiest, curliest fur and the proudest eyes and face. So, and I think you can see where I'm going with this - This way, the mutations that improve ability to hunt are not selected, and do not increase in proportion in the future generation. The mutations that improve speed and endurance will not be selected, and will not increase in proportion in the next generation. But the mutations that improve quality of coat and attractiveness in the eyes of the breeder will be selected, and will increase in proportion in the next generation.QuoteIf this is the case then no meaning can be attached to Natural selection. It is a purely random process. There is no selection involved.I hope now that you will see that this statement is simply wrong.I'm sure everyone on this forum encourages original thought, but we must take into account what is already known. Please let us know that you have decided to research evolution and natural selection further before pursuing your TSP ideas, as right now TSP can be outright rejected as it doesn't fit with known theory and observation.I am going to assume that if you still refuse to comprehend, then you are simply unwilling or unable to understand the topic that you are discussing, and I will discontinue this conversation. I hope this will not be the case.
Pet Dog breeding - take, for example, a poodle. A poodle with best adaptation to survive in the wild may not have the traits that poodle breeders want. Nor would a poodle who could run fastest, pull the heaviest load or run for longest. Poodle breeders are looking for the most handsome dog, the nicest, glossiest, curliest fur and the proudest eyes and face. So, and I think you can see where I'm going with this - This way, the mutations that improve ability to hunt are not selected, and do not increase in proportion in the future generation. The mutations that improve speed and endurance will not be selected, and will not increase in proportion in the next generation. But the mutations that improve quality of coat and attractiveness in the eyes of the breeder will be selected, and will increase in proportion in the next generation.QuoteIf this is the case then no meaning can be attached to Natural selection. It is a purely random process. There is no selection involved.I hope now that you will see that this statement is simply wrong.I'm sure everyone on this forum encourages original thought, but we must take into account what is already known. Please let us know that you have decided to research evolution and natural selection further before pursuing your TSP ideas, as right now TSP can be outright rejected as it doesn't fit with known theory and observation.I am going to assume that if you still refuse to comprehend, then you are simply unwilling or unable to understand the topic that you are discussing, and I will discontinue this conversation. I hope this will not be the case.