I need help, considering that genetic variation is the raw material of evolution.
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NatBoCheck: Well for starters even creationists believe in microevolution, but then you probably don't know what that is.\n\nGive me a few mins...\n\n"The process of evolution can be summarized in three sentences: Genes mutate. [gene: a hereditary unit] Individuals are selected. Populations evolve."\n\n"The mechanisms of evolution are mutation, natural selection, genetic drift, recombination and gene flow."\n\nMutation\n\nThe cellular machinery that copies DNA sometimes makes mistakes. These mistakes alter the sequence of a gene. This is called a mutation. There are many kinds of mutations. A point mutation is a mutation in which one "letter" of the genetic code is changed to another. Lengths of DNA can also be deleted or inserted in a gene; these are also mutations. Finally, genes or parts of genes can become inverted or duplicated. Typical rates of mutation are between 10-10 and 10-12 mutations per base pair of DNA per generation. \n\nNatural Selection\n\nSome types of organisms within a population leave more offspring than others. Over time, the frequency of the more prolific type will increase. The difference in reproductive capability is called natural selection. Natural selection is the only mechanism of adaptive evolution; it is defined as differential reproductive success of pre- existing classes of genetic variants in the gene pool.\n\nThe most common action of natural selection is to remove unfit variants as they arise via mutation. [natural selection: differential reproductive success of genotypes] In other words, natural selection usually prevents new alleles from increasing in frequency. This led a famous evolutionist, George Williams, to say "Evolution proceeds in spite of natural selection."\n\nNatural selection can maintain or deplete genetic variation depending on how it acts.\n\nGenetic Drift\n\nAllele frequencies can change due to chance alone. This is called genetic drift. Drift is a binomial sampling error of the gene pool. What this means is, the alleles that form the next generation's gene pool are a sample of the alleles from the current generation. When sampled from a population, the frequency of alleles differs slightly due to chance alone.\n\nAlleles can increase or decrease in frequency due to drift. The average expected change in allele frequency is zero, since increasing or decreasing in frequency is equally probable. A small percentage of alleles may continually change frequency in a single direction for several generations just as flipping a fair coin may, on occasion, result in a string of heads or tails. A very few new mutant alleles can drift to fixation in this manner.\n\nRecombination\n\nEach chromosome in our sperm or egg cells is a mixture of genes from our mother and our father. Recombination can be thought of as gene shuffling. Most organisms have linear chromosomes and their genes lie at specific location (loci) along them. Bacteria have circular chromosomes. In most sexually reproducing organisms, there are two of each chromosome type in every cell. For instance in humans, every chromosome is paired, one inherited from the mother, the other inherited from the father. When an organism produces gametes, the gametes end up with only one of each chromosome per cell. Haploid gametes are produced from diploid cells by a process called meiosis.\n\nIn meiosis, homologous chromosomes line up. The DNA of the chromosome is broken on both chromosomes in several places and rejoined with the other strand. Later, the two homologous chromosomes are split into two separate cells that divide and become gametes. But, because of recombination, both of the chromosomes are a mix of alleles from the mother and father.\n\nRecombination creates new combinations of alleles. Alleles that arose at different times and different places can be brought together. Recombination can occur not only between genes, but within genes as well. Recombination within a gene can fo
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Genetics and evolution.
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evolution has been proven by other means .
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1. All organisms tend to produce more offspring than can possibly survive (Darwin's generation gave this principle the lovely name of "superfecundity").\n\n2. Offspring vary among themselves, and are not carbon copies of an immutable type.\n\n3. At least some of this variation is passed down by inheritance to future generations. (Darwin did not know the mechanism of heredity, for Mendel's principles did not gain acceptance until early in our century. However, this third fact requires no knowledge of how heredity works, but only an acknowledgment that heredity exists. And mere existence is undeniable folk wisdom. We know that black folks have black kids; white folks, white kids; tall parents tend to have tall children; and so on.)\n\nThe principle of natural selection then emerges as a necessary inference from these facts:\n\n4. If many offspring must die (for not all can be accommodated in nature's limited ecology), and individuals in all species vary among themselves, then on average (as a statistical statement, and not in every case), survivors will tend to be those individuals with variations that are fortuitously best suited to changing local environments. Since heredity exists, the offspring of survivors will tend to resemble their successful parents. The accumulation of these favorable variants through time will produce evolutionary change. \n\nhttp://www.mc.maricopa.edu/dept/d10/asb/anthro2003/origins/selection/fullhouse.html
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First, kudos to you for being so open minded.\n\nI haven't read the Nat'l Geo article yet ... but I have it, and am anxious to read it.  Say what you will, the photos are breathtaking (but that's nothing new with Nat'l Geo).  And I have read several Dawkins books, but not that one. \n\nBut without hearing your specific counter-arguments, I don't know how to address them, or why you find the evidence to be "not of such high quality."  The evidence is actually *exceedingly* strong ... and most scientists accept it.\n\nI highly recommend two books in the "Beginners" series.  Specifically, "DNA for Beginners" and "Darwin for Beginners".   Don't be fooled by the cartoon format of these books ... they are excellent introductions to the science.\n\nBut if I can try and guess your point ... if the evidence of genetic linkage with *prehistoric* species is not of "high quality", it's because the DNA molecule (the source of all genetic material for all life on this planet) breaks down rather quickly.  Even a few hundred years is enough to start breaking down the DNA in the remains of animals.  And fossils rarely contain any genetic material.  However, this is not always true.  Occasionally, bone tissue can remain in fossils, and some DNA can be extracted (as we have done with Neanderthal, for example).  But overall, recovering genetic material from prehistoric animals is difficult.\n\nHowever, the genetic links can be reconstructed quite well by examining genetic similarities between living descendants of that prehistoric species.  If living species A, B, and C all have specific genes in common (code for the same protein, same location in the chromosomes, almost identical amino-acid structure), then this tells us that their common ancestor X had these genes.  If there is a fouth species D that has some, but not all the genes shared by A, B, and C ... then this indicates that there is a common ancestor Y that is further back that is the ancestor of all four living species.\n\nFuthermore, there is the concept of the 'molecular clock'.  This is the known rate at which transcription errors (basically 'typos') occur in DNA as it gets passed from generation to generation.  So the number of minor 'typos' found in the DNA of A, B, and C gives us a strong indication of how long ago their common ancestor X lived.  (For more info. see source.)\n\nI hope that helps.  It's hard to be more specific without knowing what your specific objections are.
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Step 1:  Get ahold of some tuberculosis bacteria.\n\n(Just kidding.)\n\nIt would be very very difficult to show evolution in an *experiment* because it takes hundreds or thousands of generations, which even with a super-fast reproducing species like bacteria, can take *years*. \n\nHowever, you might be able to do something with something like a mold or a fungus and some antifungal agent that killed some, but not all the fungus.  You might be able to demonstrate some resistance, within a few days, to the anti-fungal agent.  Basically, the fungus that was already vulnerable to the anti-fungal, would be eliminated quickly, leaving the more resistent strains.\n\nA better bet is *observation*.  I would recommend doing some research about flowers and polinating insects (like butterflies) in your area.  Many insects and flowers evolve together to where the insect has equipment perfectly suited for a specific plant.  E.g. a butterfly with a proboscis (nose) that is the perfect length for getting nectar out of certain flowers. \n\nAnother idea might be researching pedigrees for domesticated animals (cocker spaniels, race horses, dairy goats), or plants (orchids, roses, champion pumpkins) and look for trends that get passed down and reinforced in a certain breedlines.  Breeders tend to keep really good records going back generations.  Breeding is nothing more than evolution with humans doing the "selection".\n\nOr for fun, you can look at other evolving artifacts, like cars or computers.  E.g. the co-evolution of tires and cars.  Or guitar strings and neck truss-rods.\n\nHey Stephen Jay Gould (who loved baseball) wrote an absolutely fascinating essay about the co-evolution in baseball over the years between pitchers and hitters (the Decline of the .400 Hitter in Baseball).  (It's found in the book "Full House").  \n\nMy point is that many things can be examples of co-evolution ... it doesn't have to be biological.\n\nGood luck!
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Technicallly, everybody is a mutant! We all carry some alterations unique to us in our genomes, this is part of what makes us different. And yes, over time we will evolve as a society to carry genes that are more advantageous to us due to the process of natural selection. It's a case of survival of the fittest!
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Evolution is not directional, you can't predict what stuff will look like in a million years. And domestic animals are operating in a different environment, where people are protecting them from predators and sometimes choosing who they mate with.
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Wikipedia has a good summary:\nhttp://en.wikipedia.org/wiki/Origin_of_species\n\nAn extract from this wikipedia page:\nDarwin's theory of evolution is based on five key observations and inferences drawn from them, as summarized by the biologist Ernst Mayr:\n\nSpecies have great fertility. They make more offspring than can grow to adulthood. \nPopulations remain roughly the same size, with modest fluctuations. \nFood resources are limited, but are relatively constant most of the time. From these three observations it may be inferred that in such an environment there will be a struggle for survival among individuals. \nIn sexually reproducing species, generally no two individuals are identical. Variation is rampant. \nMuch of this variation is heritable. \nFrom this Darwin infers: In a world of stable populations where each individual must struggle to survive, those with the "best" characteristics will be more likely to survive, and those desirable traits will be passed to their offspring; and that these advantageous characteristics are inherited by following generations, becoming dominant among the population through time. This is natural selection.\n\nDarwin did not suggest that every variation and every character must have a selection value. However, he pointed out that, because of our ignorance of animal physiology and its relationship with the environment, it was extremely rash to set down any characters as valueless to their owners. It is even more important to notice that he did not suggest that every individual with a favorable variation must be selected, or that the selected or favored animals were better or higher, but merely that they were more adapted to their surroundings.\n\nDarwin further infers that natural selection, if carried far enough, makes changes in a population, eventually leading to new species. He puts forward myriad observations as demonstrations of this, and also claims that the fossil record can be interpreted as supporting these observations. Darwin imagined it might be possible that all life is descended from an original species from ancient times. Modern DNA evidence is consistent with this idea.
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No. Mutations are the ultimate source of genetic _variation_, but this random variation is shaped by various evolutionary forces (natural selection, genetic drift, migration, selective mating...).\n\n"If these spontaneous mutations are truly spontaneous than will the environmental changes caused from the worlds industrialization have an effect on the rate and manner of which these bases are put together to form amino's within protein structures which will change our genotype therefore being expressed within our phenotype?" \n--> Most mutations are either neutral (have no effect on fitness) or deletereous (have negative or mortal effects). There are pollutants that can cause increased mutations but those are usually negative and are not incorporated into the gene pool of the human population.\n\n\n"If we evolve to our environment than will the chemicals we put into our ecosystem have a gradual but significant impact on our evolutionary path?" \n--> You mean that we should go on polluting and see if any mutations arise that make us "immune" to our own contamination? I wouldn't recommend that. \n\n"... we may have to save ourselves from ourselves in order to survive by mastering and altering genetics through the deletion of the genes within chromosomes that cause undesirable genetic diseases within the gametes before artificial conception.The next step in mans' evolution is the deletion of bad genes to survive in a tainted world.After technology advances to an even higher level we must master the addition of beneficial genes through advanced genetic engineering."\n<-- We cannot do that. It will be a long time before we even begin to understand how our genome works (relatively tiny parts are know now). If we ever do that (outside movies) then I'm afraid it won't be a very equal world for everyone. \nAnd in addition: there is no such thing as GOOD or BAD genes. Any trait is well adjusted only with respect to its environment; by eliminating some characteristics that you deem "bad", you might be erasing the chance to adapt to future changes. That's why the conservation of genetic diversity is important.
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Genetics. And Darwins theory.
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i like the way you think man. the fact is howver that failure to reproduce is concidered unnatural HOWEVER! there could be a small overlooked message in the DNA that says once every so and so years people will be gay, to decrease the surplus population...i neer saw it that way im glad you enlightenemd mee
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I've read and studied to limited degree some of the standard textbooks on evolution and it has not shaken my faith, but i don't claim to be an expert, but you might want to take a look at the fact that some of the writers of standard text supporting evolution have since begun to question its ability to explain the world around us... see Dean Kenyon, he didn't read the standard graduate level text "Biochemical Evolution", he wrote it, but he has since changed his view to intelligent design.  see also Stanley Salthe he wrote the widely used text "Evolutionary Biology" (1972) as far as I know he's not a christian but he recently signed a list of over 600 scientist expressing their doubts about evolution.Even among staunch evolutionist there is widespread disagreement as to how or if current theories can adequately explain the complexity and diversity of life. Don't let an oversimplified pop culture understanding of evolution mislead you into thinking the universe is understood and God has been somehow disproved/discredited or made irrelevant. Evolutionary theory has in no way proven we are here by chance. see www.wasdarwinwrong   its a good survey of pro-darwin, neo-darwin, alternative and intelligent design literature.  see also  discovery.org and reasonstobelieve.org  don't fail to examine the claims of Christ because a theory of biological origins
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Not possible. Genetics give you what you have, be thankful for it.
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Not to mention, a 3 percent difference in genetics is a vast difference.  Enough to render a separate and distinct species.
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Geniology through evolution,that will take thousands of years.So we will just have to do the best we can.
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Post an addendum to your question - you don't need a whole new question.\n\nLeoin is obviously blissfully unaware (or more likely doesn't want to hear) that man and ape SHARED a common ancestor and evolution is based on branches not strength lines.\n\nOne more bit of amateur science to try to bolster an obviously wavering faith.