Alright nerds, first and foremost, the universe is accurately dated at 13.7 billion years old. Its nearly indisputable and widely accepted. http://www.nasa.gov/centers/goddard/...apresults.html
Honestly, and i'll expand if you wish, there is not enough time (based on the age of our universe) for amino acid mutations to take place in the volume necessary to support macro-evolution. I'll borrow here a bit
"Think again about our average human protein of 469 amino acids, with specified sequence. Let's assume that by the design process the correct amino acid sequence was assembled so that our protein can function, as an enzyme or in a structural capacity. But wait, and wait some more, and sorry, keep waiting… each amino acid has two rotatable bonds, known as phi and psi (ignore that this is a wild underestimate because it neglects sidechain conformations). Each of those bonds can assume three possible rotations (called rotameric states). Therefore a protein of 469 amino acids has 3^469 possible conformational states (10^223 states). Since bonds change their rotational state about 10 times in a picosecond, our average human protein of 469 amino acid will take 10^202 years, or 10^193 billion years, to fold, to randomly find that one single conformational state known as the native state. The chance that the average human protein will fold by random processes during the 10 billion year existence of the universe is way way way less than the Little Willie's Universal Probability Bound. This little secret is known to biochemists, who do not talk about it to outsiders, as the ‘Levinthal Paradox’
If you and I and our families and friends and their families and their friends started randomly combining amino acids hoping to stumble upon a 469 amino acid protein of specified sequence, we would never, never, never, not in a billion billion years, never, never, ever succeed. Even if we had enough time, the earth would run out of carbon before we slogged our way out of that vast random sequence space. Most possible proteins have not been made, neither by nature nor in the laboratory, and never will be made. Protein sequence space is essentially unexplored. "
Furthemore, Micro-evolution is a fact. Nobody has ever disputed this that has a fundemental understanding of what micro-evolution is.
However, there are three big problems with Macro-evolution, which is what those who believe in radical changes between species occuring (such as humans evolving from monkey's or fish over millions/billions of years.)
Irreducibly complex changes, dna limitations, an inability add information to dna.
When a trait is critical for the survival of the species, it must be fully functional or the species will die off and any ‘evolutionary progress’ would be lost. For example, a bat could not evolve from a rodent because it is completely dependent on its wings for survival. A half-evolved wing could not be used for walking because of its awkward length and shape and would not be functional for flying. The idea of a half-evolved bat is completely illogical. It would be easily tracked down by predators and it would be helpless to get food and survive on its own. This need for completeness can be clearly observed from the most primitive single celled animal to the most complex mammal. To contradict this idea would clearly contradict Darwin’s principle of natural selection. Many scientists are making a shift because gradual change produces dysfunction in-between species. The new emerging proposal is the quantum jump.
I reccomend reading Darwin's Black Box for some more information on this.
A fact of genetics is that trait changes have a ceiling. This perhaps is the biggest obstacle to gradual change through micro-evolution. Each rung of DNA is made up of four chemicals called nucleotides, designated by the symbols: A (adenine), G (guanine), C (cytosine), and T (thymine). These rungs of DNA are combined to provide a blueprint of the traits that organism will have. If you took all the DNA in the human body and put it in written format, it would fill up one million volumes the size of a 500 page encyclopedia. With all this genetic data, if two people could have as many children as there are atoms in the universe, no two children would be identical. Though there are a limitless combinations of traits that we possess, there is a limit to how far each trait can change. There is a limit to the number of combinations of these chemicals; therefore there are a limited number of trait variations. No new genetic material can be added. Trait changes result in re-arranging the genetic code that is already present. Mixing the available genetic code will produce variations in the trait but will not change into a completely different feature. For example, your parents genes are combined to produce your various traits. People have several different colors of hair, eyes, and skin, but without a mutation, these traits will remain within its boundaries. There are mutations that can occur and mutations almost always cause diseases or defects. However, even under mutation, skin will still be skin and eyes will still be eyes. Because of the code barrier, there are a limited number of variations in eye color. Different genes can create distinct variations but there is a limit. There can be rapid changes but inevitably, there is a return to the norm.
Honestly, and i'll expand if you wish, there is not enough time (based on the age of our universe) for amino acid mutations to take place in the volume necessary to support macro-evolution. I'll borrow here a bit
"Think again about our average human protein of 469 amino acids, with specified sequence. Let's assume that by the design process the correct amino acid sequence was assembled so that our protein can function, as an enzyme or in a structural capacity. But wait, and wait some more, and sorry, keep waiting… each amino acid has two rotatable bonds, known as phi and psi (ignore that this is a wild underestimate because it neglects sidechain conformations). Each of those bonds can assume three possible rotations (called rotameric states). Therefore a protein of 469 amino acids has 3^469 possible conformational states (10^223 states). Since bonds change their rotational state about 10 times in a picosecond, our average human protein of 469 amino acid will take 10^202 years, or 10^193 billion years, to fold, to randomly find that one single conformational state known as the native state. The chance that the average human protein will fold by random processes during the 10 billion year existence of the universe is way way way less than the Little Willie's Universal Probability Bound. This little secret is known to biochemists, who do not talk about it to outsiders, as the ‘Levinthal Paradox’
If you and I and our families and friends and their families and their friends started randomly combining amino acids hoping to stumble upon a 469 amino acid protein of specified sequence, we would never, never, never, not in a billion billion years, never, never, ever succeed. Even if we had enough time, the earth would run out of carbon before we slogged our way out of that vast random sequence space. Most possible proteins have not been made, neither by nature nor in the laboratory, and never will be made. Protein sequence space is essentially unexplored. "
Furthemore, Micro-evolution is a fact. Nobody has ever disputed this that has a fundemental understanding of what micro-evolution is.
However, there are three big problems with Macro-evolution, which is what those who believe in radical changes between species occuring (such as humans evolving from monkey's or fish over millions/billions of years.)
Irreducibly complex changes, dna limitations, an inability add information to dna.
When a trait is critical for the survival of the species, it must be fully functional or the species will die off and any ‘evolutionary progress’ would be lost. For example, a bat could not evolve from a rodent because it is completely dependent on its wings for survival. A half-evolved wing could not be used for walking because of its awkward length and shape and would not be functional for flying. The idea of a half-evolved bat is completely illogical. It would be easily tracked down by predators and it would be helpless to get food and survive on its own. This need for completeness can be clearly observed from the most primitive single celled animal to the most complex mammal. To contradict this idea would clearly contradict Darwin’s principle of natural selection. Many scientists are making a shift because gradual change produces dysfunction in-between species. The new emerging proposal is the quantum jump.
I reccomend reading Darwin's Black Box for some more information on this.
A fact of genetics is that trait changes have a ceiling. This perhaps is the biggest obstacle to gradual change through micro-evolution. Each rung of DNA is made up of four chemicals called nucleotides, designated by the symbols: A (adenine), G (guanine), C (cytosine), and T (thymine). These rungs of DNA are combined to provide a blueprint of the traits that organism will have. If you took all the DNA in the human body and put it in written format, it would fill up one million volumes the size of a 500 page encyclopedia. With all this genetic data, if two people could have as many children as there are atoms in the universe, no two children would be identical. Though there are a limitless combinations of traits that we possess, there is a limit to how far each trait can change. There is a limit to the number of combinations of these chemicals; therefore there are a limited number of trait variations. No new genetic material can be added. Trait changes result in re-arranging the genetic code that is already present. Mixing the available genetic code will produce variations in the trait but will not change into a completely different feature. For example, your parents genes are combined to produce your various traits. People have several different colors of hair, eyes, and skin, but without a mutation, these traits will remain within its boundaries. There are mutations that can occur and mutations almost always cause diseases or defects. However, even under mutation, skin will still be skin and eyes will still be eyes. Because of the code barrier, there are a limited number of variations in eye color. Different genes can create distinct variations but there is a limit. There can be rapid changes but inevitably, there is a return to the norm.
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