People who have never studied science, not even to the extent of taking a high school biology or physics course (or even finishing high school!), are the most likely to make grievous errors whenever they venture into deep scientific waters. Most often they do so to try to make a specious case to support a pet belief, or some biblical reference or book- but if they mess up on their scientific facts, they do themselves no service.
I want to look here at further errors commonly made by critics to do with evolution, and argue again, that before they wade into waylaying Darwinian natural selection they at least avail themselves of an online video course – if not attend or audit a real life course!
1) Micro-evolution:
The definition of micro-evolution from an actual text on it by an expert (Strickberger, on Evolution) is as follows:
Changes in the genetic makeup in a population that usually gives rise to differences between populations of a given species in the form of gene frequency changes or chromosomal variations.
Since the latter DO incorporate genetic changes, then these micro-evolutionary changes can ultimately accumulate and lead to taxonomic or macro-evolutionary changes.
Thus, it is incorrect to asset “there is no new genetic information” being produced.
As an example let’s focus in on the pesticide resistant bedbug population and show that their resistance is also a genetic change, not merely a genotype-less “adaptation”.
We will here consider a diploid population of 200 individuals, and 400 genes distributed amongst them. As we saw from the table given (previous blog on evolution) the ratio of gene frequencies between the homozygous dominant allele (B) and the homozygous recessive allele (b)is 3:2 or 0.60: 0.40 which could manifest for the case shown via:
B = 180 (in BB) + 60 (in Bb) = 240/400 = 0.60
b = 100 (in bb) + 60 (in Bb) = 160/400 = 0.40
For the 200 individual bedbugs we find the genotype frequencies distributed such that 90 are homozygous dominant (resistant to all known approved pesticides) = 90, and 50 are heterozygous Bb, while 50 are homozygous recessive (not resistant) = bb = 50, therefore for the dominant and recessive allele distributions using genotype frequencies:
B = 0.45 BB + ½(.30Bb) = 0.45 + 0.15 = 0.60
b = 0.25 BB + ½(.30Bb) = 0.25 + 0.15 = 0.40
The preceding would conform to the values for p, q in the top row of the table (see, http://brane-space.blogspot.com/2010/09/problems-with-evolution-hardly.html
And display the conservation of gene frequencies for that line of the table. Now, for a STABLE population, IF the gene pool (of a selected population, whether bedbugs, roaches or fruit flies) remains constant from one generation to the next then the Hardy -Weinberg theorem applies and genetic variation is retained from one generation to the next. We say the population is in “stasis” and there is NO micro-evolution occurring. (Note again, the letters p and q in the table denote the two alleles in the population, i.e. p = B, q = b, thus if B is found to enhance or increase over b then p will increase over q and we will have micro-evolution, which is exactly what we see as we go from the top down in the table)
The sum of the frequencies of all possible genotypes will, in any case, be:
p^2 + 2pq + q^2 =1
which can be verified from the table, for example:
when p = 0.73 and q = 0.27:
(0.73)^2 + 2(0.73)(0.27) + (0.27)^2 = 1
But the key point to glean from the table is that p is increasing all the time, and q is decreasing. In other words the frequency of the dominant allele is enhancing its fitness in relation to the recessive, and micro-evolution is not only vindicated, but the allele re-distributions show a genetic component IS present!
Is this micro-evolution also adaptation – which is defined as meaning that a character (e.g. eye color, resistance to toxins) has been modified and retained as a result of selection for increased fitness? Yes, indeed! But that doesn’t mean no new genetic information is through put! As we see from inspection of the table (and the gene frequency distribution changes) new genetic information is present in the altered quantitative frequency of p relative to q. “New information” being not merely qualitative but also quantitative in nature.
The creationist claim that “adaptation” (and with it micro-evolution) fits within its perspective misses the point that this can only be valid if the genotype frequencies remain stable (Refer to chart at top of page) But since they do not, as seen from the table, then micro-evolution cannot be the same as a simple one-off adaptation that enables no further changes in gene frequency.
Now what conditions are needed for there to be an “evolutionary” change? These include:
1) Variation must exist among the individuals of a population (e.g. if all bedbugs possess the same allele, e.g. b, then there is no variation)
2) Variation among individuals results in differences in number of offspring surviving in the next generation. As we see from inspection of the table this is born out. Thus, the first generation allows 60 of every 100 bedbugs to survive, while the second allows 73 of every hundred to survive, while the third allows 83 of every 100 to survive.
3) Variation must be genetically inherited. Thus, for natural selection to result in evolutionary change, the selected differences must have a genetic basis. Thus, a “lucky” b allele bedbug that simply somehow survives a battery of allowed pesticides isn’t enough. There must be a dominant genetic input, in this case a dominant allele – we call it B- which predisposes for resistance to pesticides.
Note here that one can have a population that is all phenotypically difference (e.g. by appearance) but does not display genetic variation, Then there is no evolution. By contrast, one can have a phenotypically similar population that does display genetic difference. For an evolutionary change to occur in the bedbug population as captured by the table, we must expect that the p favoritism is not merely temporary but passed on and established in all future bedbug populations.
Macroevolution:
As noted earlier, macroevolution, by contrast, entails a proportionately large change in the DNA underlying it that probably reflects ongoing natural selection, over significant time. For example, the change from a cold-blooded dinosaur to a warm-blooded dinosaur that’s a precursor of modern birds would be a case of macroevolution. Similarly, the change from an ape-human ancestor to Homo sapiens (by telomeric fusion of the 2p and 2q chromosomes to the ‘2’ chromosome in humans) would be a case of macroevolution, despite the fact the evidence is available at the chromosomal level.A claim often made by creationists is that macro-evolution “has never been proven or observed”, but this is false! The clear changes in reptilian scales to feathers which we have in hand as evidence from the most primitive feathered dinosaur (the recently reported discovery of fossilized tail feathers of a meat eating dinosaur, Sinosauropteryx found in China) belies this.
The image shown (top) captures the creature (superposed in the tail scale) and its russet-hue. In addition, this dinosaur appears to have russet rings. Most intriguing, the pigmentation of the 125-million year old dinosaur appears to exhibit the same internal cellular coloring agents as seen in the hair of red-headed humans.
The color itself did not show up on simple observation, but did once an electron microscope was applied, at which point the researchers (based at the University of Bristol, England) identified the specific cellular markers of color. Until this remarkable find, scientists have speculated on a wide range of colors for these prehistoric beasts - ranging from rich pastoral green, to ochre and brown. Not surprisingly, as the connection to birds came more and more to light, so did researchers' consciousness that color might be an evolutionary factor.
An important aspect of the macro-evolutionary linkage to descendant birds is that Sinosauropteryx co-existed with other scaled flying dinosaurs.
Another evidence for macro-evolution in terms of a common ancestor of apes and humans giving rise to both is the fact that the cytochrome –c protein sequence has been found to be exactly the same in both.
In the absence of common descent, the chance of this occurrence is conservatively less than ~10^-93 (1 out of 10^93 or 10 followed by 93 zeros). Thus, the high degree of similarity in these proteins is a spectacular corroboration of the theory of common descent. Furthermore, human and chimpanzee cytochrome- c proteins differ by ~10 amino acids from all other mammals. The chance of this occurring in the absence of a hereditary mechanism is less than 10^-29. The yeast Candida krusei is one of the most distantly related eukaryotic organisms from humans. Candida has 51 amino acid differences from the human sequence. A conservative estimate of this probability is less than 10^-25.
An odd fundie objection to common ancestry, is that it is only “circumstantial”. However, the fact of the exact same cytochrome-c sequence to both species (with vanishing probabilities this can happen any other way) plus the fact the 2p and 2q chromosomes fused telomerically to yield the 2 chromosome in humans yields prima facie evidence for not only macro-evolution but common ancestry – that is both chimps and humans descending from a common primate ancestor.
Some fundies also claim this can be explained by a common “creator” but that stretches credulity to profound dimensions! Why would a bona fide “creator” create two species with features (cytochrome-c protein sequence) that argue against a creator! Given that macro-evolution is a simpler hypothesis, and the protein sequence given is explainable via natural selection, one doesn’t require any creator, period! The fallacy committed is what we call “ignotum per ignotius” or using a more far fetched explanation to account for somewhat difficult phenomena.
Fundies also insist that the human mind (presumably of evolutionists) is simply looking at relationships and finding them where it wants to, but this doesn’t hold up under scrutiny. The exactness of the two protein sequences is a real relationship and not merely an ersatz one, as validated by the vanishing small probabilities we find by comparing the sequence with other organisms! As noted earlier, the yeast Candida krusei is one of the most distantly related eukaryotic organisms from humans. Candida has 51 amino acid differences from the human sequence. Thus, the cytochrome –c sequence is a marker for evolutionary commonality or relatedness. The fact that the 2p and 2q chromosomes in apes have also undergone telomeric fusion in humans to yield the ‘2’ further reinforces this and knocks out happenstance or coincidental patterns!
To make a howler comment like: “Lining up bacteria , fish , frogs , mammals , apes , and humans is no more evidence of common ancestry than lining up a bicycle , motorcycle , automobile , airplane , and space shuttle .” is pure silliness, as well as committing the logical fallacies of: non sequitur and false analogy- since mechanical contrivances lack the protein sequence being used to establish common ancestry in the first place! No one is arguing the mechanical contraptions listed derive from a common ancestry since every one with two brain cells to rub together knows that mechanical devices don’t reproduce! Nor do they possess genes!In addition, common ancestry is contingent on examination of protein sequences but mechanical devices lack protein! (No one to my knowledge, even a fundie, has ever eaten one!) In other words, this is purely a strawman argument.
We see from this that the most misinformed critics inevitably use the most simplistic arguments to try to bat down evolution, such as we are merely invoking “similarity” to make a case, say for common descent and evolution – as opposed to having actual genetic and other evidence (as in the case of the Sinosauropteryx fossil, to support it.
What this reveals, again, is that non-science folk are better off sticking to their bibles or cartoons, comics and not venturing into scientific domains, period. They will never know as much as scientists, or experts in the field – especially if they’ve never taken a course on the subject themselves – and base everything they know on Genesis, or Googling.
I want to look here at further errors commonly made by critics to do with evolution, and argue again, that before they wade into waylaying Darwinian natural selection they at least avail themselves of an online video course – if not attend or audit a real life course!
1) Micro-evolution:
The definition of micro-evolution from an actual text on it by an expert (Strickberger, on Evolution) is as follows:
Changes in the genetic makeup in a population that usually gives rise to differences between populations of a given species in the form of gene frequency changes or chromosomal variations.
Since the latter DO incorporate genetic changes, then these micro-evolutionary changes can ultimately accumulate and lead to taxonomic or macro-evolutionary changes.
Thus, it is incorrect to asset “there is no new genetic information” being produced.
As an example let’s focus in on the pesticide resistant bedbug population and show that their resistance is also a genetic change, not merely a genotype-less “adaptation”.
We will here consider a diploid population of 200 individuals, and 400 genes distributed amongst them. As we saw from the table given (previous blog on evolution) the ratio of gene frequencies between the homozygous dominant allele (B) and the homozygous recessive allele (b)is 3:2 or 0.60: 0.40 which could manifest for the case shown via:
B = 180 (in BB) + 60 (in Bb) = 240/400 = 0.60
b = 100 (in bb) + 60 (in Bb) = 160/400 = 0.40
For the 200 individual bedbugs we find the genotype frequencies distributed such that 90 are homozygous dominant (resistant to all known approved pesticides) = 90, and 50 are heterozygous Bb, while 50 are homozygous recessive (not resistant) = bb = 50, therefore for the dominant and recessive allele distributions using genotype frequencies:
B = 0.45 BB + ½(.30Bb) = 0.45 + 0.15 = 0.60
b = 0.25 BB + ½(.30Bb) = 0.25 + 0.15 = 0.40
The preceding would conform to the values for p, q in the top row of the table (see, http://brane-space.blogspot.com/2010/09/problems-with-evolution-hardly.html
And display the conservation of gene frequencies for that line of the table. Now, for a STABLE population, IF the gene pool (of a selected population, whether bedbugs, roaches or fruit flies) remains constant from one generation to the next then the Hardy -Weinberg theorem applies and genetic variation is retained from one generation to the next. We say the population is in “stasis” and there is NO micro-evolution occurring. (Note again, the letters p and q in the table denote the two alleles in the population, i.e. p = B, q = b, thus if B is found to enhance or increase over b then p will increase over q and we will have micro-evolution, which is exactly what we see as we go from the top down in the table)
The sum of the frequencies of all possible genotypes will, in any case, be:
p^2 + 2pq + q^2 =1
which can be verified from the table, for example:
when p = 0.73 and q = 0.27:
(0.73)^2 + 2(0.73)(0.27) + (0.27)^2 = 1
But the key point to glean from the table is that p is increasing all the time, and q is decreasing. In other words the frequency of the dominant allele is enhancing its fitness in relation to the recessive, and micro-evolution is not only vindicated, but the allele re-distributions show a genetic component IS present!
Is this micro-evolution also adaptation – which is defined as meaning that a character (e.g. eye color, resistance to toxins) has been modified and retained as a result of selection for increased fitness? Yes, indeed! But that doesn’t mean no new genetic information is through put! As we see from inspection of the table (and the gene frequency distribution changes) new genetic information is present in the altered quantitative frequency of p relative to q. “New information” being not merely qualitative but also quantitative in nature.
The creationist claim that “adaptation” (and with it micro-evolution) fits within its perspective misses the point that this can only be valid if the genotype frequencies remain stable (Refer to chart at top of page) But since they do not, as seen from the table, then micro-evolution cannot be the same as a simple one-off adaptation that enables no further changes in gene frequency.
Now what conditions are needed for there to be an “evolutionary” change? These include:
1) Variation must exist among the individuals of a population (e.g. if all bedbugs possess the same allele, e.g. b, then there is no variation)
2) Variation among individuals results in differences in number of offspring surviving in the next generation. As we see from inspection of the table this is born out. Thus, the first generation allows 60 of every 100 bedbugs to survive, while the second allows 73 of every hundred to survive, while the third allows 83 of every 100 to survive.
3) Variation must be genetically inherited. Thus, for natural selection to result in evolutionary change, the selected differences must have a genetic basis. Thus, a “lucky” b allele bedbug that simply somehow survives a battery of allowed pesticides isn’t enough. There must be a dominant genetic input, in this case a dominant allele – we call it B- which predisposes for resistance to pesticides.
Note here that one can have a population that is all phenotypically difference (e.g. by appearance) but does not display genetic variation, Then there is no evolution. By contrast, one can have a phenotypically similar population that does display genetic difference. For an evolutionary change to occur in the bedbug population as captured by the table, we must expect that the p favoritism is not merely temporary but passed on and established in all future bedbug populations.
Macroevolution:
As noted earlier, macroevolution, by contrast, entails a proportionately large change in the DNA underlying it that probably reflects ongoing natural selection, over significant time. For example, the change from a cold-blooded dinosaur to a warm-blooded dinosaur that’s a precursor of modern birds would be a case of macroevolution. Similarly, the change from an ape-human ancestor to Homo sapiens (by telomeric fusion of the 2p and 2q chromosomes to the ‘2’ chromosome in humans) would be a case of macroevolution, despite the fact the evidence is available at the chromosomal level.A claim often made by creationists is that macro-evolution “has never been proven or observed”, but this is false! The clear changes in reptilian scales to feathers which we have in hand as evidence from the most primitive feathered dinosaur (the recently reported discovery of fossilized tail feathers of a meat eating dinosaur, Sinosauropteryx found in China) belies this.
The image shown (top) captures the creature (superposed in the tail scale) and its russet-hue. In addition, this dinosaur appears to have russet rings. Most intriguing, the pigmentation of the 125-million year old dinosaur appears to exhibit the same internal cellular coloring agents as seen in the hair of red-headed humans.
The color itself did not show up on simple observation, but did once an electron microscope was applied, at which point the researchers (based at the University of Bristol, England) identified the specific cellular markers of color. Until this remarkable find, scientists have speculated on a wide range of colors for these prehistoric beasts - ranging from rich pastoral green, to ochre and brown. Not surprisingly, as the connection to birds came more and more to light, so did researchers' consciousness that color might be an evolutionary factor.
An important aspect of the macro-evolutionary linkage to descendant birds is that Sinosauropteryx co-existed with other scaled flying dinosaurs.
Another evidence for macro-evolution in terms of a common ancestor of apes and humans giving rise to both is the fact that the cytochrome –c protein sequence has been found to be exactly the same in both.
In the absence of common descent, the chance of this occurrence is conservatively less than ~10^-93 (1 out of 10^93 or 10 followed by 93 zeros). Thus, the high degree of similarity in these proteins is a spectacular corroboration of the theory of common descent. Furthermore, human and chimpanzee cytochrome- c proteins differ by ~10 amino acids from all other mammals. The chance of this occurring in the absence of a hereditary mechanism is less than 10^-29. The yeast Candida krusei is one of the most distantly related eukaryotic organisms from humans. Candida has 51 amino acid differences from the human sequence. A conservative estimate of this probability is less than 10^-25.
An odd fundie objection to common ancestry, is that it is only “circumstantial”. However, the fact of the exact same cytochrome-c sequence to both species (with vanishing probabilities this can happen any other way) plus the fact the 2p and 2q chromosomes fused telomerically to yield the 2 chromosome in humans yields prima facie evidence for not only macro-evolution but common ancestry – that is both chimps and humans descending from a common primate ancestor.
Some fundies also claim this can be explained by a common “creator” but that stretches credulity to profound dimensions! Why would a bona fide “creator” create two species with features (cytochrome-c protein sequence) that argue against a creator! Given that macro-evolution is a simpler hypothesis, and the protein sequence given is explainable via natural selection, one doesn’t require any creator, period! The fallacy committed is what we call “ignotum per ignotius” or using a more far fetched explanation to account for somewhat difficult phenomena.
Fundies also insist that the human mind (presumably of evolutionists) is simply looking at relationships and finding them where it wants to, but this doesn’t hold up under scrutiny. The exactness of the two protein sequences is a real relationship and not merely an ersatz one, as validated by the vanishing small probabilities we find by comparing the sequence with other organisms! As noted earlier, the yeast Candida krusei is one of the most distantly related eukaryotic organisms from humans. Candida has 51 amino acid differences from the human sequence. Thus, the cytochrome –c sequence is a marker for evolutionary commonality or relatedness. The fact that the 2p and 2q chromosomes in apes have also undergone telomeric fusion in humans to yield the ‘2’ further reinforces this and knocks out happenstance or coincidental patterns!
To make a howler comment like: “Lining up bacteria , fish , frogs , mammals , apes , and humans is no more evidence of common ancestry than lining up a bicycle , motorcycle , automobile , airplane , and space shuttle .” is pure silliness, as well as committing the logical fallacies of: non sequitur and false analogy- since mechanical contrivances lack the protein sequence being used to establish common ancestry in the first place! No one is arguing the mechanical contraptions listed derive from a common ancestry since every one with two brain cells to rub together knows that mechanical devices don’t reproduce! Nor do they possess genes!In addition, common ancestry is contingent on examination of protein sequences but mechanical devices lack protein! (No one to my knowledge, even a fundie, has ever eaten one!) In other words, this is purely a strawman argument.
We see from this that the most misinformed critics inevitably use the most simplistic arguments to try to bat down evolution, such as we are merely invoking “similarity” to make a case, say for common descent and evolution – as opposed to having actual genetic and other evidence (as in the case of the Sinosauropteryx fossil, to support it.
What this reveals, again, is that non-science folk are better off sticking to their bibles or cartoons, comics and not venturing into scientific domains, period. They will never know as much as scientists, or experts in the field – especially if they’ve never taken a course on the subject themselves – and base everything they know on Genesis, or Googling.
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