Wednesday, 30 November 2016
Using I.D to disprove I.D.
"What about evolution is random and what is not?"
Robert Crowther
Here's another one for my "you can't make this stuff up" file. I kid you not, this is a news story about a new peer-reviewed paper in PLoS Biology by Brian Paegel and Gerald Joyce of The Scripps Research Institute which explains that (all emphasis from here on is mine)
they have produced a computer-controlled system that can drive the evolution of improved RNA enzymes.
I couldn't write a funnier script if I tried. Sadly, these guys just don't get the joke.
The evolution of molecules via scientific experiment is not new. The first RNA enzymes to be "evolved" in the lab were generated in the 1990s. But what is exciting about this work is that the process has been made automatic. Thus evolution is directed by a machine without requiring human intervention-other then providing the initial ingredients and switching the machine on.
But wait it gets better.
Throughout the process, the evolution-machine can propagate the reaction itself, because whenever the enzyme population size reaches a predetermined level, the machine removes a fraction of the population and replaces the starting chemicals needed for the reaction to continue.
What? Predetermined? Predetermined by whom or by what? Oh, the evolution machine, which itself is a result of intelligent agency.
The authors sum it all up very nicely.
This beautifully illustrates what about evolution is random and what is not.
Robert Crowther
Here's another one for my "you can't make this stuff up" file. I kid you not, this is a news story about a new peer-reviewed paper in PLoS Biology by Brian Paegel and Gerald Joyce of The Scripps Research Institute which explains that (all emphasis from here on is mine)
they have produced a computer-controlled system that can drive the evolution of improved RNA enzymes.
I couldn't write a funnier script if I tried. Sadly, these guys just don't get the joke.
The evolution of molecules via scientific experiment is not new. The first RNA enzymes to be "evolved" in the lab were generated in the 1990s. But what is exciting about this work is that the process has been made automatic. Thus evolution is directed by a machine without requiring human intervention-other then providing the initial ingredients and switching the machine on.
But wait it gets better.
Throughout the process, the evolution-machine can propagate the reaction itself, because whenever the enzyme population size reaches a predetermined level, the machine removes a fraction of the population and replaces the starting chemicals needed for the reaction to continue.
What? Predetermined? Predetermined by whom or by what? Oh, the evolution machine, which itself is a result of intelligent agency.
The authors sum it all up very nicely.
This beautifully illustrates what about evolution is random and what is not.
Missing links v. Darwin.
Billions of Missing Links: Hen's Eggs
Geoffrey Simmons
Note: This is one of a series of posts excerpted from my book, Billions of Missing Links: A Rational Look at the Mysteries Evolution Can't Explain
.
When it comes to citing examples of purposeful design, nearly every author likes to point out the hen's egg. It's really quite remarkable. Despite having a shell that is a mere 0.35 mm think, they don't break when a parent sits on them. According to Dr. Knut Schmidt-Nielsen,
A bird egg is a mechanical structure strong enough to hold a chick securely during development, yet weak enough to break out of. The shell must let oxygen in and carbon dioxide out, yet be sufficiently impermeable to water to keep the contents from drying out.
Under microscopy, one can see the shell is a foamlike structure that resists cracking. Gases and water pass through 10,000 pores that average 17 micrometers in diameter. Ultimately, 6 liters of oxygen will have been taken in and 4.5 liters of carbon dioxide given off. The yolk is its food. All life support systems are self-contained, like a space shuttle.
All hen's eggs are ready to hatch on the twenty-first day. Every day is precisely preprogrammed. The heart starts beating on the sixth day. On the nineteenth day the embryo uses its egg tooth to puncture the air sac (beneath the flat end) and then takes two days to crack through the shell.
Giving natural selection a hand?
The Rest of the Story -- Eugenics, Racism, Darwinism
Sarah Chaffee
According to its most ardent proponents, a widespread embrace of evolutionary theory is a big win-win not only for science but for culture and ethics. Our recent report "Darwin's Corrosive Idea" handily dispels that rosy picture as it pertains to the present day. As for history, Jason Jones and John Zmirak writing at The Stream helpfully remind readers of the link between eugenics, racism, and Darwinism.
Their specific topic is Margaret Sanger and the documentary Maafa 21: Black Genocide. Here's what they say about Darwin and how his arguments were used to justify eugenics:
The eugenicists' arrogant certainty that, because they had inherited money and power, they were genetically superior to the rest of the human race, found in Charles Darwin's theories an ideal pretext and a program: to take the survival of the fittest and make it happen faster, by stopping the "unfit" from breeding. The goal, in Margaret Sanger's own words, was "More Children from the Fit, Fewer from the Unfit." Instead of seeing the poor as victims of injustice or targets for Christian charity, the materialism these elitists took from Darwin assured them that the poor were themselves the problem -- that they were inferior, deficient and dangerous down to the marrow of their bones.
The authors note that the eugenics movement itself was undergirded by racism. The video Maafa 21, they note, links the rise of eugenics to white anxiety about the "negro problem" following the end of the Civil War.
In his book Darwin Day in America, Center for Science & Culture associate director John West has written extensively about the social damage linked to Darwinism.
Jones and Zmirak bring up some harrowing examples, among them the observation that Sanger's friend Lothrop Stoddard was a leader in the Massachusetts Klu Klux Klan and wrote a book Hitler called his "bible." A speaker Sanger invited to a population conference, Eugen Fisher, had operated a concentration camp in Africa imprisoning natives. Jones and Zimrak note, "It was Fischer's book on eugenics, which Hitler had read in prison, that convinced Hitler of its central importance." For more historical background, read historian Richard Weikart's books including his most recent, Hitler's Religion.
They say that history is written by the victors. With evolutionary theory holding sway in the media and academia, it's little wonder we rarely hear about these connections and events.
Life's machine code v. Darwin.
My Dear Watson: Four Observations on the DNA Code and Evolution
Cornelius Hunter
The DNA code is used in cells to translate a sequence of nucleotides into a sequence of amino acids, which then make up a protein. In the past fifty years we have learned four important things about the code:
1. The DNA code is universal. There are minor variations scattered about, but the same canonical code is found across the species.
2. The DNA code is special. The DNA is not just some random, off the shelf, code. It has unique properties that, for example, make the translation process more robust to mutations. The code has been called "one in a million
," but it probably is even more special than that. One
study
found that the code optimizes "a combination of several different functions simultaneously."
3. Some of the special properties of the DNA code only rarely confer benefit. Many of the code's special properties deal with rare mutation events. If such properties could arise via random mutation in an individual organism, their benefit would not be common.
4. The DNA code's fitness landscape has dependencies on the DNA coding sequences and so favors stasis. Changes in the DNA code may well wreak havoc as the DNA coding sequences are suddenly not interpreted correctly. So the fitness landscape, at any given location in the code design space, is not only rugged but often is a local minimum, thus freezing evolution at that code.
Observation #1 above, according to evolutionary theory, means that the code is the ultimate homology and must have been present in the last universal common ancestor (LUCA). There was essentially zero evolution of the code allowed over the course of billions of years.
This code stasis can be understood, from an evolutionary perspective, using Observation #4. Given the many dependencies on the DNA coding sequences, the code can be understood to be at a local minimum and so impossible to evolve.
Hence Francis Crick's characterization, and subsequent promotion by later evolutionists, of the code as a "frozen accident." Somehow the code arose, but was then strongly maintained and unevolvable.
But then there is Observation #2. The code has been found to be not mundane, but special. This falsified the "frozen accident" characterization, as the code is clearly not an accident. It also caused a monumental problem. While evolutionists could understand Observation #1, the universality of the code, as a consequence of the code being at a fitness local minimum, Observation #2 tells us that the code would not have just luckily been constructed at its present design.
If evolution somehow created a code to begin with, it would be at some random starting point. Evolution would have no a priori knowledge of the fitness landscape. There is a large number of possible codes, so it would be incredibly lucky for evolution's starting point to be anywhere near the special, canonical code we observe today. There would be an enormous evolutionary distance to travel between an initial random starting point, and the code we observe.
And yet there is not even so much as a trace of such a monumental evolutionary process. This would be an incredible convergence. In biology, when we see convergence, we usually also see variety. The mammalian and cephalopod eyes are considered to be convergent, but they also have fundamental differences. And in other species, there are all kinds of different vision systems. The idea that the universal DNA code is the result of convergence would be very suspect. Why are there no other canonical codes found? Why are there not more variants of the code? To have that much evolutionary distance covered, and converge with that level of precision would very strange.
And of course, in addition to this strange absence of any evidence of such a monumental evolutionary process, there is the problem described above with evolving the code to begin with. The code's fitness landscape is rugged and loaded with many local minima. Making much progress at all in evolving the code would be difficult.
But then there is Observation #3. Not only do we not see traces of the required monumental process of evolving the code across a great distance, and not only would this process be almost immediately halted by the many local minima in the fitness landscape, but what fitness improvements could actually be realized would not likely be selected for because said improvements rarely actually confer their benefit.
While these problems are obviously daunting, we have so far taken yet another tremendous problem for granted: the creation of the initial code, as a starting point.
We have discussed above the many problems with evolving today's canonical code from some starting point, all the while allowing for such a starting point simply to magically appear. But that, alone, is a big problem for evolution. The evolution of any code, even a simple code, from no code, is a tremendous problem.
Finally, a possible explanation for these several and significant problems to the evolution of the DNA code is the hypothesis that the code did not actually evolve so much as construct. Just as the right sequence of amino acids will inevitably fold into a functional protein, so too perhaps the DNA code simply is the consequence of biochemical interactions and reactions. In this sense the code would not evolve from random mutations, but rather would be inevitable. In that case, there would be no lengthy evolutionary pathway to traverse.
Now I don't want to give the impression that this hypothesis is mature or fleshed out. It is extremely speculative. But there is another, more significant, problem with it: It is not evolution.
If true, this hypothesis would confirm design. In other words, a chemically determined pathway, which as such is written into the very fabric of matter and nature's laws, would not only be profound but teleological. The DNA code would be built into biochemistry.
And given Observation #2, it is a very special, unique, detailed, code that would be built into biochemistry. It would not merely be a mundane code that happened to be enabled or determined by biochemistry, but essentially an optimized code. Long live Aristotle.
The problem is there simply is no free lunch. Evolutionists can try to avoid the science, but there it is.
Nature's world wide web v. Darwin.
Evolutionist Recommends "Listening to Other Arguments," Except When It Comes to Evolution
David Klinghoffer
We may be on the third wave of a scientific revolution in biology. It may be so big, the story "no doubt has Ernst Mayr hyperventilating in his grave," thinks evolutionary biologist Nora Besansky of the University of Notre Dame. Mayr influenced a generation of evolutionists. Is one of his core Darwinian concepts unraveling? In Science Magazine, Elizabeth Pennisi sets the stage:
Most of those who studied animals had instead bought into the argument by the famous mid-20th century evolutionary biologist Ernst Mayr that the formation of a new species requires reproductive isolation. Mayr and his contemporaries thought that the offspring of any hybrids would be less fit or even infertile, and would not persist. To be sure, captive animals could be interbred: Breeders crossed the African serval cat with domestic cats to produce the Savannah cat, and the Asian leopard cat with domestic breeds to produce the Bengal cat. There's even a "liger," the result of a zoo mating of a tiger and a lion. But like male mules, male ligers are sterile, supporting the notion that in nature, hybridization is mostly a dead end. [Emphasis added.]
Indeed, the biological concept of "species" practically requires reproductive isolation. Hybridization, while known since ancient civilizations bred mules, seems unnatural and rare. It played little role in classical Darwinian theory, which relies on emergent variation and selection for the origin of species. According to hybridization specialist Eugene M. McCarthy in "Darwin's Assessment of Hybridization," "Darwin did come to attribute more significance to hybridization in his later years," but it never gained significant traction in any edition of the Origin, his most widely read book. "Certainly such ideas were never canonized among the dogmas of neo-Darwinian theory."
For Darwin's branching tree-of-life diagram to work, innovations must be passed along in ancestor-descendent relationships, moving vertically up the branches over time by inheritance of chance mutations. Hybrids interfere with this picture by allowing branches to share genetic information horizontally all at once. And if the branches can re-join by back-crossing, the tree metaphor becomes more like a net. Pennisi understands the challenge to Darwinism in her title, "Shaking Up the Tree of Life," when she says, "Species were once thought to keep to themselves. Now, hybrids are turning up everywhere, challenging evolutionary theory."
The revolution has come in three waves. The first involved microbes, when horizontal gene transfer (HGT), sometimes called lateral gene transfer (LGT), was found to be common (see Denyse O'Leary's article last year, "Horizontal Gene Transfer: Sorry, Darwin, It's Not Your Evolution Any More"). HGT doesn't just complicate efforts to construct phylogenetic trees, she says; "because where HGT is in play, there just isn't a tree of life." In another Evolution News article, Paul Nelson cites Woese, Koonin and other evolutionists going out on a limb to dispute the existence of a universal tree of life -- at least when it comes to the origin of the three kingdoms of microbes.
The second wave involved plants. As far back as 1949, Pennisi says, it was a radical idea to suggest that plant species shared genes via hybridization. Botanists grew to accept the idea, but zoologists resisted it:
In 1949, botanist Edgar Anderson suggested that plants could take on genes from other species through hybridization and back crosses, where the hybrid mates with the parent species. He based this then-radical proposal on genetic crosses and morphological studies of flowering plants and ferns suggesting mixtures of genes from different species in individual genomes. Five years later, with fellow botanist G. Ledyard Stebbins, he argued such gene exchange could lead to new plant species. Their ideas quickly hit home with other plant researchers, but not with zoologists. "There was a very different conventional view in botany than in zoology," Rieseberg says.
Now, the third wave is encompassing the rest of biology: animals. (This wave hits close to home, involving as it does the human lineage.) Starting in the 1990s, zoologists began seeing hybridization as more than a breeder's trick. Pennisi gives three examples of the growing realization that natural hybridization contributes to speciation in animals, too.
Darwin's finches: Peter and Rosemary Grant witnessed a hybrid finch establishing its own population, with its own phenotype, in its own ecological niche. Pennisi tells the story of "Big Bird" in a separate Science Magazine article.
Butterflies: James Mallet's work on Ecuadorian butterflies a decade ago, borrowing on earlier work by Larry Gilbert, proved that more than 30% of Heliconius species formed hybrids, "swapping wing patterns and sometimes generating entirely new ones."
Neandertals: "In 2010, a comparison between the genomes of a Neandertal and people today settled what anthropologists and geneticists had debated for decades: Our ancestors had indeed mated with their archaic cousins, producing hybrid children," Pennisi says in the lead story. "They, in turn, had mated with other modern humans, leaving their distant descendants -- us -- with a permanent Neandertal legacy. Not long afterward, DNA from another archaic human population, the Denisovans, also showed up in the modern human genome, telling a similar story."
Finding hybridization in the human lineage "created a shock wave," Pennisi says. She quotes Malcolm Arnold whose imagination was captured by this important but long overlooked aspect of inheritance. "That genomic information overturned the assumption that everyone had." Pennisi helps us consider the implications for evolutionary theory:
The techniques that revealed the Neandertal and Denisovan legacy in our own genome are now making it possible to peer into the genomic histories of many organisms to check for interbreeding. The result: "Almost every genome study where people use sensitive techniques for detecting hybridization, we find [it] -- we are finding hybridization events where no one expected them," says Loren Reiseberg, an evolutionary biologist at the University of British Columbia in Vancouver, Canada.
All these data belie the common idea that animal species can't hybridize or, if they do, will produce inferior or infertile offspring -- think mules. Such reproductive isolation is part of the classic definition of a species. But many animals, it is now clear, violate that rule: Not only do they mate with related species, but hybrid descendants are fertile enough to contribute DNA back to a parental species -- a process called introgression.
The revolution was slow in coming till rapid genomic sequencing techniques became available. Now, with a plenitude of sequences published, what biologists had come to accept in microbes is forcing them to reconsider what they thought they knew about evolution for the entire tree of life. Pennisi all but announces the revolution:
Biologists long ago accepted that microbes can swap DNA, and they are now coming to terms with rampant gene flow among more complex creatures. "A large percent of the genome is free to move around," notes Chris Jiggins, an evolutionary biologist at the University of Cambridge in the United Kingdom. This "really challenges our concept of what a species is." As a result, where biologists once envisioned a tree of life, its branches forever distinct, many now see an interconnected web.
Hybridization, says Mallet, "has become big news and there's no escaping it."
The tree metaphor is being replaced with a net or web. That's the point where Pennisi describes Ernst Mayr, Darwin's paramount tree gardener, hyperventilating in his grave. In a new world of rampant hybridization and introgression, what is to become of neo-Darwinism? Pennisi gives a glimpse of the implications, hinting at a revolutionary new view of the origin of species. Putting a happy face on the revolution, she ends this way:
The Grants believe that complete reproductive isolation is outdated as a definition of a species. They have speculated that when a species is no longer capable of exchanging genes with any other species, it loses evolutionary potential and may become more prone to extinction.
This idea has yet to be proven, and even Mallet concedes that biologists don't fully understand how hybridization and introgression drive evolution -- or how to reconcile these processes with the traditional picture of species diversifying and diverging over time. Yet for him and for others, these are heady times. "It's the world of hybrids," Rieseberg says. "And that's wonderful."
It will certainly be wonderful for intelligent design theorists, but it's hard to see how Darwinians will cope with the revolution. Why? Because HGT and hybridization involve the shuffling of pre-existing genetic information, not the origin of new genetic information. Information isn't emerging by accidental mutations; it is being shared in a biological World Wide Web! Pennisi suggests this may be advantageous:
As examples of hybridization have multiplied, so has evidence that, at least in nature, swapping DNA has its advantages. When one toxic butterfly species acquires a gene for warning coloration from another toxic species, both species benefit, as a single encounter with either species is now enough to teach predators to avoid both. Among canids, interbreeding with domestic dogs has given wolves in North America a variant of the gene for an immune protein called Î’-defensin. The variant gives wolf-dog hybrids and their descendants a distinctive black pelt and better resistance to canine distemper, Wayne says. In Asia, wolf-dog matings may have helped Tibetan mastiffs cope with the thin air at high altitudes. And interspecies gene flow has apparently allowed insecticide resistance to spread among malaria-carrying mosquitoes and the black flies that transmit river blindness.
In each case, the beneficial genetic changes unfolded faster than they would have by the normal process of mutation, which often changes DNA just one base at a time. Given the ability of hybridization and introgression to speed adaptive changes, says Baird, "closing that door [with reproductive isolation] is not necessarily going to be a good thing for your long-term survival."
Think of the possibilities for design theorists. We can see strategies for robustness with information sharing, allowing animals to survive environmental perturbations or recharge damaged genomes, for instance. Indeed, all kinds of "wonderful" possibilities open up for exploring design when information sharing is available in the explanatory toolkit. New vistas for explaining symbioses, ecosystems, and variability emerge. Could some apparent "innovations" be loans from other species? How can the information-sharing biosphere inform practical applications for medicine?
In the wonderful new "world of hybrids," ID advocates can take the lead, breathing new life into biological explanations, while the neo-Darwinists hyperventilate to delay the inevitable.
David Klinghoffer
We may be on the third wave of a scientific revolution in biology. It may be so big, the story "no doubt has Ernst Mayr hyperventilating in his grave," thinks evolutionary biologist Nora Besansky of the University of Notre Dame. Mayr influenced a generation of evolutionists. Is one of his core Darwinian concepts unraveling? In Science Magazine, Elizabeth Pennisi sets the stage:
Most of those who studied animals had instead bought into the argument by the famous mid-20th century evolutionary biologist Ernst Mayr that the formation of a new species requires reproductive isolation. Mayr and his contemporaries thought that the offspring of any hybrids would be less fit or even infertile, and would not persist. To be sure, captive animals could be interbred: Breeders crossed the African serval cat with domestic cats to produce the Savannah cat, and the Asian leopard cat with domestic breeds to produce the Bengal cat. There's even a "liger," the result of a zoo mating of a tiger and a lion. But like male mules, male ligers are sterile, supporting the notion that in nature, hybridization is mostly a dead end. [Emphasis added.]
Indeed, the biological concept of "species" practically requires reproductive isolation. Hybridization, while known since ancient civilizations bred mules, seems unnatural and rare. It played little role in classical Darwinian theory, which relies on emergent variation and selection for the origin of species. According to hybridization specialist Eugene M. McCarthy in "Darwin's Assessment of Hybridization," "Darwin did come to attribute more significance to hybridization in his later years," but it never gained significant traction in any edition of the Origin, his most widely read book. "Certainly such ideas were never canonized among the dogmas of neo-Darwinian theory."
For Darwin's branching tree-of-life diagram to work, innovations must be passed along in ancestor-descendent relationships, moving vertically up the branches over time by inheritance of chance mutations. Hybrids interfere with this picture by allowing branches to share genetic information horizontally all at once. And if the branches can re-join by back-crossing, the tree metaphor becomes more like a net. Pennisi understands the challenge to Darwinism in her title, "Shaking Up the Tree of Life," when she says, "Species were once thought to keep to themselves. Now, hybrids are turning up everywhere, challenging evolutionary theory."
The revolution has come in three waves. The first involved microbes, when horizontal gene transfer (HGT), sometimes called lateral gene transfer (LGT), was found to be common (see Denyse O'Leary's article last year, "Horizontal Gene Transfer: Sorry, Darwin, It's Not Your Evolution Any More"). HGT doesn't just complicate efforts to construct phylogenetic trees, she says; "because where HGT is in play, there just isn't a tree of life." In another Evolution News article, Paul Nelson cites Woese, Koonin and other evolutionists going out on a limb to dispute the existence of a universal tree of life -- at least when it comes to the origin of the three kingdoms of microbes.
The second wave involved plants. As far back as 1949, Pennisi says, it was a radical idea to suggest that plant species shared genes via hybridization. Botanists grew to accept the idea, but zoologists resisted it:
In 1949, botanist Edgar Anderson suggested that plants could take on genes from other species through hybridization and back crosses, where the hybrid mates with the parent species. He based this then-radical proposal on genetic crosses and morphological studies of flowering plants and ferns suggesting mixtures of genes from different species in individual genomes. Five years later, with fellow botanist G. Ledyard Stebbins, he argued such gene exchange could lead to new plant species. Their ideas quickly hit home with other plant researchers, but not with zoologists. "There was a very different conventional view in botany than in zoology," Rieseberg says.
Now, the third wave is encompassing the rest of biology: animals. (This wave hits close to home, involving as it does the human lineage.) Starting in the 1990s, zoologists began seeing hybridization as more than a breeder's trick. Pennisi gives three examples of the growing realization that natural hybridization contributes to speciation in animals, too.
Darwin's finches: Peter and Rosemary Grant witnessed a hybrid finch establishing its own population, with its own phenotype, in its own ecological niche. Pennisi tells the story of "Big Bird" in a separate Science Magazine article.
Butterflies: James Mallet's work on Ecuadorian butterflies a decade ago, borrowing on earlier work by Larry Gilbert, proved that more than 30% of Heliconius species formed hybrids, "swapping wing patterns and sometimes generating entirely new ones."
Neandertals: "In 2010, a comparison between the genomes of a Neandertal and people today settled what anthropologists and geneticists had debated for decades: Our ancestors had indeed mated with their archaic cousins, producing hybrid children," Pennisi says in the lead story. "They, in turn, had mated with other modern humans, leaving their distant descendants -- us -- with a permanent Neandertal legacy. Not long afterward, DNA from another archaic human population, the Denisovans, also showed up in the modern human genome, telling a similar story."
Finding hybridization in the human lineage "created a shock wave," Pennisi says. She quotes Malcolm Arnold whose imagination was captured by this important but long overlooked aspect of inheritance. "That genomic information overturned the assumption that everyone had." Pennisi helps us consider the implications for evolutionary theory:
The techniques that revealed the Neandertal and Denisovan legacy in our own genome are now making it possible to peer into the genomic histories of many organisms to check for interbreeding. The result: "Almost every genome study where people use sensitive techniques for detecting hybridization, we find [it] -- we are finding hybridization events where no one expected them," says Loren Reiseberg, an evolutionary biologist at the University of British Columbia in Vancouver, Canada.
All these data belie the common idea that animal species can't hybridize or, if they do, will produce inferior or infertile offspring -- think mules. Such reproductive isolation is part of the classic definition of a species. But many animals, it is now clear, violate that rule: Not only do they mate with related species, but hybrid descendants are fertile enough to contribute DNA back to a parental species -- a process called introgression.
The revolution was slow in coming till rapid genomic sequencing techniques became available. Now, with a plenitude of sequences published, what biologists had come to accept in microbes is forcing them to reconsider what they thought they knew about evolution for the entire tree of life. Pennisi all but announces the revolution:
Biologists long ago accepted that microbes can swap DNA, and they are now coming to terms with rampant gene flow among more complex creatures. "A large percent of the genome is free to move around," notes Chris Jiggins, an evolutionary biologist at the University of Cambridge in the United Kingdom. This "really challenges our concept of what a species is." As a result, where biologists once envisioned a tree of life, its branches forever distinct, many now see an interconnected web.
Hybridization, says Mallet, "has become big news and there's no escaping it."
The tree metaphor is being replaced with a net or web. That's the point where Pennisi describes Ernst Mayr, Darwin's paramount tree gardener, hyperventilating in his grave. In a new world of rampant hybridization and introgression, what is to become of neo-Darwinism? Pennisi gives a glimpse of the implications, hinting at a revolutionary new view of the origin of species. Putting a happy face on the revolution, she ends this way:
The Grants believe that complete reproductive isolation is outdated as a definition of a species. They have speculated that when a species is no longer capable of exchanging genes with any other species, it loses evolutionary potential and may become more prone to extinction.
This idea has yet to be proven, and even Mallet concedes that biologists don't fully understand how hybridization and introgression drive evolution -- or how to reconcile these processes with the traditional picture of species diversifying and diverging over time. Yet for him and for others, these are heady times. "It's the world of hybrids," Rieseberg says. "And that's wonderful."
It will certainly be wonderful for intelligent design theorists, but it's hard to see how Darwinians will cope with the revolution. Why? Because HGT and hybridization involve the shuffling of pre-existing genetic information, not the origin of new genetic information. Information isn't emerging by accidental mutations; it is being shared in a biological World Wide Web! Pennisi suggests this may be advantageous:
As examples of hybridization have multiplied, so has evidence that, at least in nature, swapping DNA has its advantages. When one toxic butterfly species acquires a gene for warning coloration from another toxic species, both species benefit, as a single encounter with either species is now enough to teach predators to avoid both. Among canids, interbreeding with domestic dogs has given wolves in North America a variant of the gene for an immune protein called Î’-defensin. The variant gives wolf-dog hybrids and their descendants a distinctive black pelt and better resistance to canine distemper, Wayne says. In Asia, wolf-dog matings may have helped Tibetan mastiffs cope with the thin air at high altitudes. And interspecies gene flow has apparently allowed insecticide resistance to spread among malaria-carrying mosquitoes and the black flies that transmit river blindness.
In each case, the beneficial genetic changes unfolded faster than they would have by the normal process of mutation, which often changes DNA just one base at a time. Given the ability of hybridization and introgression to speed adaptive changes, says Baird, "closing that door [with reproductive isolation] is not necessarily going to be a good thing for your long-term survival."
Think of the possibilities for design theorists. We can see strategies for robustness with information sharing, allowing animals to survive environmental perturbations or recharge damaged genomes, for instance. Indeed, all kinds of "wonderful" possibilities open up for exploring design when information sharing is available in the explanatory toolkit. New vistas for explaining symbioses, ecosystems, and variability emerge. Could some apparent "innovations" be loans from other species? How can the information-sharing biosphere inform practical applications for medicine?
In the wonderful new "world of hybrids," ID advocates can take the lead, breathing new life into biological explanations, while the neo-Darwinists hyperventilate to delay the inevitable.
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