People who know next to zippo about Darwinian evolution (they haven’t even read Darwin’s Origin of Species) constantly complain about perceived “problems with evolution” but most of these are McGuffins, red herrings, straw men or false issues. Let’s consider first the claimed contradiction between gradualism, the hypothesis that speciation occurs only slowly via natural selection vs. Punctuated equilibrium which essentially has implied the converse (sudden and dramatic speciation). More technically, the latter actually refers to a differential rate of selection as opposed to what was believed a 'constant rate' of selection for the former- despite the fact no actual "gradualist" holds that a single steady constant rate is do-able or necessary!
So in many ways this is a false dichotomy and false argument. The term “punctuated equilibria” was originally coined by paleontologists Eldredge and (Stephen J.) Gould to denote a long-term fossil uniformity of populations punctuated by geologically short period of rapid speciation. However, none of the critics of the alleged “face off” between “gradualism” and “punctualism” seem to be remotely aware that 99.9% of evolutionists agree that BOTH gradual and rapid changes can occur in the course of evolution! (Again a case of false either-or logic getting the better of critics, leading them to falsely conclude the two aspects are “mutually exclusive” when they are not)
As Biologist Richard Dawkins puts it (‘The Blind Watchmaker’, p. 248):
“Punctuationists then, are just as gradualist as Darwin or any other Darwinian. They just insert long periods of stasis between spurts of gradual evolution.”
Dawkins then goes on to clarify why the discussion has become so muddied, mainly because of a misuse of the term ‘gradualism’- which was first coined to distinguish Darwinian natural selection from saltationism (which as he points out is actually a glorified creationism). The latter can best be framed by the description “all at once evolution” in which a species suddenly – over maybe one generation or two – becomes a whole new species. But neither punctuationists nor gradualists make any such claim! (Which is why Dawkins also calls it “747 evolution” because it would be like seventy thousand pounds of nuts, bolts, panels, diodes, electric wires and junk suddenly coalescing as a Boeing 747 without the slow process of manufacture!)
The other unfortunate overtone in all this, was the fact that Gould et al deliberately used the phrase “punctuated evolution” as if their version was somehow distinct in kind from gradualism, never reminding non-scientific Americans that the term ‘gradualism’ preceded their own use – by virtue of Darwin’s invocation of it to distinguish it from saltationism. In this way, “punctuated equilibrium” arose more out of media stardom and the endless media need for controversy than any abiding reality. In a genuine sense, then, the controversy of punctuated evolution v. gradualism is a strawman confected by the media, much as they recently confected the “climategate crisis” out of hacked emails, when three panels and independent commissions found that no real crisis ever existed! Moral of the story? Never ever trust the media to get it right!
What about alleged fossil problems associated with evolution, or as some critics aver, “gradualism” (given we now use this word only casually and not formally!) Well, as Dawkins observes we do know that most of the major invertebrate groups seem to suddenly appear in the Cambrian rock strata of 600 million years ago as if “planted” (Op. cit., p. 229) Evolutionists concede this leaves a large hole or gap in the fossil record, but one which is not without logical explanation! Consider the backward time trajectory within which we see fossils by older layers (dated using radioactive decay – as I showed in a prior blog) accumulating the further back we go. We see a bunch of invertebrates at 600 my ago but virtually nothing before. Why? A logical explanation is that even more primitive forms pre-existed these and their soft exo-skeleta or body parts would simply not have survived. In other words there were no shells or bones to fossilize! Think of just a large primitive jellyfish, would we find fossil evidence for it? Hardly! The creature is 100% soft tissue none of which would have been preserved,. Same with most other more primitive denizens.
Again, this explanation is accepted by BOTH punctualists and gradualists so to try to split them off from each other, as if the fossil record gaps fail gradualism but not punctualism is a false choice and shows the critic doesn’t know what he’s writing about.
Another reason for apparent “jerks” in the fossil record is offered by Prof. Dawkins (p. 240)
“The reason that the transition from ancestral species to descendant species appears to be jerky is simply that, when we look at a series of fossils from any one place, we are probably not looking at an evolutionary event at all, but a migrational event. The arrival of a new species from another geographical area”
I mean, after all, there’s no law that commands all species remain fixed in one place! Even today, as water holes dry up or food reserves dip, African animals like Wildebeest, antelope and others will migrate to new areas in search of resources to support them.
Not mentioned by Dawkins is how many other ‘holes” or gaps may have been created by virtue of tectonic plates (which make up the Earth’s crust) slipping or crushing key fossils in distinct layers. Obviously, if such tectonic traversal displaced a fossil layer, then it likely won’t be found when it may well have harbored intermediate forms.
What about alleged conflicts between micro-evolution and macro-evolution? Once again, these are more based on inflated hot air (especially from brash creationists and bible pounders) than substance.
By “micro-evolution” we mean minute evolutionary change, involving a small proportion of DNA. For example, the emergence of an orange-eyed fruit fly (drosophilia melanogaster) after 20 generations would demonstrate microevolution. Of course, microevolution can also appear at the microscopic level, for example in changes in haemoglobins, histo-compatability antigens, and biochemical environmental adaptations (e.g. formation of blood chemicals which confer some form of restance to environmental toxins or agents).
For example, right now a hardy form of bedbug has arisen, impervious to nearly all forms of insecticide and the reason why these annoying creatures are now dominating the news cycle- and driving millions to distraction. This change occurred somewhat suddenly, as one examines the statistics for infestation, with barely 50 cases in New York City in 2006 vs. more than 3,000 this year. The evidence then suggest clearly a punctuated equilibrium in terms of micro-evolution in the bedbugs species leading to a resistance to nearly all insecticides.
In terms of the concept of fitness let B refer to a favored allele for a bedbug with total resistance, let b refer to a deleterious allele ( one with zero resistance) Recall the measures for success of natural selection are the fitness (w) and the selective value (s): These can be measured on either absolute or relative scales, but are related algebraically on the latter by:
w = 1 – s, or s = 1 – w
Let’s say at a particular time a gene frequency ‘snapshot’ of the bedbug population under study yields: p(B) = 0.60, q(b) = 0.40, i.e. the favored allele B is reproducing at the ratio 3:2 relative to the disadvantaged one, b. As before, the selective value s = 0.50. A simple table showing the declining gene frequency of b relative to B is shown appended to this blog
On average over time let each bb and Bb individual produce one offspring, and each BB produce two. These average numbers can be used to indicate the genotype’s absolute fitness and to project the changes in gene frequency over succeeding generations. The relative fitness (w) is meanwhile given by:
w = 1 for BB
w = 0.5 for Bb
w = 0.5 for bb
The selection values, relative measures of the reduction of fitness for each genotype, are given respectively by:
s = 1 – 1 = 0 for BB
s = 1 – 0.5 = 0.5 for Bb
s = 1 – 0.5 = 0.5 for bb
As we expect, the pesticide-resistant bedbug genotype displays zero reduction in fitness, and hence maximum survival rate. Thus, the table provides a brief “snapshot” of how micro-evolution has been working in the bedbug population to generate billions of these pests that can’t be exterminated by ordinary pesticides – necessitating the use of varieties currently prohibited for safety and health reasons.
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.
As another point to note in this discussion, punctuated evolutionists don’t see any sharp divergence between the micro-evolutionary foundation and macro-evolution in their formulation. Thus, they see the fossil record as long intervals of micro-evolutionary stasis or equilibrium – during which there is relatively little change, punctuated by rapid macro-evolutionary emergence. (Which again, is not to be confused with saltationism, thus in this case what is going on micro-evolutionarily in an apparent equilibrium – may simply not be visible at the macro-scale, but which ultimately incepts macro-scale features. E.g. scales suddenly converted to feathers for raptors).
What does all this show? That most of the alleged "problems of evolution" are confections or fabrications which exist only in the minds of those who insist on seeing problems - perhaps beause "problems" with evolution assuage some doubts that their good Book gives them the whole truth. What is somewhat puzzling, and I've never been able to process is: Why, if their good Book provides them with all the truth needed, they feel compelled to venture into scientific arenas they know nothing about? Is it to try and pretend they know some science to confer an imagined gravitas on their beliefs? (Or to use big words like "punctuated evolution" and "gradualism" - to show off for their followers?) WHY? Why not then just have "faith" that their nonsense is true and leave evolution to the evolutionists? That's a question only these zealots can answer! But we can be sure they never will, at least honestly!
So in many ways this is a false dichotomy and false argument. The term “punctuated equilibria” was originally coined by paleontologists Eldredge and (Stephen J.) Gould to denote a long-term fossil uniformity of populations punctuated by geologically short period of rapid speciation. However, none of the critics of the alleged “face off” between “gradualism” and “punctualism” seem to be remotely aware that 99.9% of evolutionists agree that BOTH gradual and rapid changes can occur in the course of evolution! (Again a case of false either-or logic getting the better of critics, leading them to falsely conclude the two aspects are “mutually exclusive” when they are not)
As Biologist Richard Dawkins puts it (‘The Blind Watchmaker’, p. 248):
“Punctuationists then, are just as gradualist as Darwin or any other Darwinian. They just insert long periods of stasis between spurts of gradual evolution.”
Dawkins then goes on to clarify why the discussion has become so muddied, mainly because of a misuse of the term ‘gradualism’- which was first coined to distinguish Darwinian natural selection from saltationism (which as he points out is actually a glorified creationism). The latter can best be framed by the description “all at once evolution” in which a species suddenly – over maybe one generation or two – becomes a whole new species. But neither punctuationists nor gradualists make any such claim! (Which is why Dawkins also calls it “747 evolution” because it would be like seventy thousand pounds of nuts, bolts, panels, diodes, electric wires and junk suddenly coalescing as a Boeing 747 without the slow process of manufacture!)
The other unfortunate overtone in all this, was the fact that Gould et al deliberately used the phrase “punctuated evolution” as if their version was somehow distinct in kind from gradualism, never reminding non-scientific Americans that the term ‘gradualism’ preceded their own use – by virtue of Darwin’s invocation of it to distinguish it from saltationism. In this way, “punctuated equilibrium” arose more out of media stardom and the endless media need for controversy than any abiding reality. In a genuine sense, then, the controversy of punctuated evolution v. gradualism is a strawman confected by the media, much as they recently confected the “climategate crisis” out of hacked emails, when three panels and independent commissions found that no real crisis ever existed! Moral of the story? Never ever trust the media to get it right!
What about alleged fossil problems associated with evolution, or as some critics aver, “gradualism” (given we now use this word only casually and not formally!) Well, as Dawkins observes we do know that most of the major invertebrate groups seem to suddenly appear in the Cambrian rock strata of 600 million years ago as if “planted” (Op. cit., p. 229) Evolutionists concede this leaves a large hole or gap in the fossil record, but one which is not without logical explanation! Consider the backward time trajectory within which we see fossils by older layers (dated using radioactive decay – as I showed in a prior blog) accumulating the further back we go. We see a bunch of invertebrates at 600 my ago but virtually nothing before. Why? A logical explanation is that even more primitive forms pre-existed these and their soft exo-skeleta or body parts would simply not have survived. In other words there were no shells or bones to fossilize! Think of just a large primitive jellyfish, would we find fossil evidence for it? Hardly! The creature is 100% soft tissue none of which would have been preserved,. Same with most other more primitive denizens.
Again, this explanation is accepted by BOTH punctualists and gradualists so to try to split them off from each other, as if the fossil record gaps fail gradualism but not punctualism is a false choice and shows the critic doesn’t know what he’s writing about.
Another reason for apparent “jerks” in the fossil record is offered by Prof. Dawkins (p. 240)
“The reason that the transition from ancestral species to descendant species appears to be jerky is simply that, when we look at a series of fossils from any one place, we are probably not looking at an evolutionary event at all, but a migrational event. The arrival of a new species from another geographical area”
I mean, after all, there’s no law that commands all species remain fixed in one place! Even today, as water holes dry up or food reserves dip, African animals like Wildebeest, antelope and others will migrate to new areas in search of resources to support them.
Not mentioned by Dawkins is how many other ‘holes” or gaps may have been created by virtue of tectonic plates (which make up the Earth’s crust) slipping or crushing key fossils in distinct layers. Obviously, if such tectonic traversal displaced a fossil layer, then it likely won’t be found when it may well have harbored intermediate forms.
What about alleged conflicts between micro-evolution and macro-evolution? Once again, these are more based on inflated hot air (especially from brash creationists and bible pounders) than substance.
By “micro-evolution” we mean minute evolutionary change, involving a small proportion of DNA. For example, the emergence of an orange-eyed fruit fly (drosophilia melanogaster) after 20 generations would demonstrate microevolution. Of course, microevolution can also appear at the microscopic level, for example in changes in haemoglobins, histo-compatability antigens, and biochemical environmental adaptations (e.g. formation of blood chemicals which confer some form of restance to environmental toxins or agents).
For example, right now a hardy form of bedbug has arisen, impervious to nearly all forms of insecticide and the reason why these annoying creatures are now dominating the news cycle- and driving millions to distraction. This change occurred somewhat suddenly, as one examines the statistics for infestation, with barely 50 cases in New York City in 2006 vs. more than 3,000 this year. The evidence then suggest clearly a punctuated equilibrium in terms of micro-evolution in the bedbugs species leading to a resistance to nearly all insecticides.
In terms of the concept of fitness let B refer to a favored allele for a bedbug with total resistance, let b refer to a deleterious allele ( one with zero resistance) Recall the measures for success of natural selection are the fitness (w) and the selective value (s): These can be measured on either absolute or relative scales, but are related algebraically on the latter by:
w = 1 – s, or s = 1 – w
Let’s say at a particular time a gene frequency ‘snapshot’ of the bedbug population under study yields: p(B) = 0.60, q(b) = 0.40, i.e. the favored allele B is reproducing at the ratio 3:2 relative to the disadvantaged one, b. As before, the selective value s = 0.50. A simple table showing the declining gene frequency of b relative to B is shown appended to this blog
On average over time let each bb and Bb individual produce one offspring, and each BB produce two. These average numbers can be used to indicate the genotype’s absolute fitness and to project the changes in gene frequency over succeeding generations. The relative fitness (w) is meanwhile given by:
w = 1 for BB
w = 0.5 for Bb
w = 0.5 for bb
The selection values, relative measures of the reduction of fitness for each genotype, are given respectively by:
s = 1 – 1 = 0 for BB
s = 1 – 0.5 = 0.5 for Bb
s = 1 – 0.5 = 0.5 for bb
As we expect, the pesticide-resistant bedbug genotype displays zero reduction in fitness, and hence maximum survival rate. Thus, the table provides a brief “snapshot” of how micro-evolution has been working in the bedbug population to generate billions of these pests that can’t be exterminated by ordinary pesticides – necessitating the use of varieties currently prohibited for safety and health reasons.
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.
As another point to note in this discussion, punctuated evolutionists don’t see any sharp divergence between the micro-evolutionary foundation and macro-evolution in their formulation. Thus, they see the fossil record as long intervals of micro-evolutionary stasis or equilibrium – during which there is relatively little change, punctuated by rapid macro-evolutionary emergence. (Which again, is not to be confused with saltationism, thus in this case what is going on micro-evolutionarily in an apparent equilibrium – may simply not be visible at the macro-scale, but which ultimately incepts macro-scale features. E.g. scales suddenly converted to feathers for raptors).
What does all this show? That most of the alleged "problems of evolution" are confections or fabrications which exist only in the minds of those who insist on seeing problems - perhaps beause "problems" with evolution assuage some doubts that their good Book gives them the whole truth. What is somewhat puzzling, and I've never been able to process is: Why, if their good Book provides them with all the truth needed, they feel compelled to venture into scientific arenas they know nothing about? Is it to try and pretend they know some science to confer an imagined gravitas on their beliefs? (Or to use big words like "punctuated evolution" and "gradualism" - to show off for their followers?) WHY? Why not then just have "faith" that their nonsense is true and leave evolution to the evolutionists? That's a question only these zealots can answer! But we can be sure they never will, at least honestly!
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