Reading furnishes the mind only with materials of knowledge; it is thinking that makes what we read ours.
John locke.
John locke.
Sunday 7 August 2016
On the supposed solution to the cambrian mystery or "It came from outer space"
To Create Cambrian Animals, Whack the Earth from Space
Evolution News & Views
It's surely not a coincidence that this season in science-journal publishing we've seen a variety of attempts to solve the enigma that Stephen Meyer describes in his new book, Darwin's Doubt. The problem, of course, is how to account for the geologically sudden eruption of complex new life forms in the Cambrian explosion. Meyer argues that the best explanation is intelligent design.
The orthodox materialist camp in mainstream science remains in full denial mode. They can't stomach the proposal of ID, but neither can they for the most part bring themselves to answer Meyer by name, or even admit there's a controversy on the subject. Charles Marshall, reviewing the book in Science, is the honorable exception. So we get what look like stealth responses to Meyer's book that claim to have figured out the Cambrian puzzle without telling you what the urgency for doing so really is, thus evading the task of responding to Meyer directly. (See David Klinghoffer's review of the reviewers of Darwin's Doubt, "A Taxonomy of Evasion.")
Probably the most hopeless solution so far ascribes some of the creative power to a blast in the ocean by a space impact. This supposedly helped "set the stage" for the rapid proliferation of new animal forms. When we examine the complexity of a single Cambrian fossil, though, such a notion, like the others on offer, leaves all the important questions unanswered.
To his credit, Grant M. Young, the author of the proposal, is somewhat modest in the way he formulates his idea. His paper in GSA Today is primarily concerned with looking for evidence of a "very large marine impact" prior to the Ediacaran Period that sent vast quantities of water and oxygen into the atmosphere, changed the obliquity of Earth's spin axis, and altered sea levels. The aftermath of that catastrophe, he speculates, played a role in the Cambrian explosion -- but a "crucial" one.
Attendant unprecedented environmental reorganization may have played a crucial role in the emergence of complex life forms. (Emphasis added.)
That's all Young had to say about it, but the suggestion was enough for NASA's Astrobiology Magazine to jump on it with a breathless headline: "Did a Huge Impact Lead to the Cambrian Explosion?" Author Johnny Bontemps catapulted that tease into the notion that "The ensuing environmental re-organization would have then set the stage for the emergence of complex life." Bontemps is correct about one thing:
These events marked the beginning of another drastic event known as the Cambrian explosion. Animal life on Earth suddenly blossomed, with all of the major groups of animals alive today making their first appearance.
Let's take a look at just one of the Cambrian animals, as seen in an exquisitely preserved new fossil from the Chengjiang strata in China, where so many beautiful fossils have been found (examples are shown in the Illustra film Darwin's Dilemma). The new fossil, Alalcomenaeus, published by Nature, was furnished with multiple claws like other Cambrian arthropods, but was so well preserved its nervous system could be outlined in detail. Even though it is dated from the early Cambrian at 520 million years old, it already had the nerves of modern spiders. Co-author Nick Strausfeld explains:
"We now know that the megacheirans had central nervous systems very similar to today's horseshoe crabs and scorpions," said Strausfeld, the senior author of the study and a Regents' Professor in the UA's Department of Neuroscience. "This means the ancestors of spiders and their kin lived side by side with the ancestors of crustaceans in the Lower Cambrian."'
Though tiny (about an inch long), its nervous system must have been fairly advanced, because the elongated creature was capable of swimming or crawling or both. In addition to about a dozen body segments with jointed appendages, it had a "pair of long, scissor-like appendages attached to the head, most likely for grasping or sensory purposes." It also had two pairs of eyes.
Iron deposits selectively accumulated in the nerve cells, allowing the research team to reconstruct the highly organized brain and nervous system. After processing with CT scans and iron scans, "out popped this beautiful nervous system in startling detail."
Comparing the outline of the fossil nervous system to nervous systems of horseshoe crabs and scorpions left no doubt that 520-million-year-old Alalcomenaeus was a member of the chelicerates.
Specifically, the fossil shows the typical hallmarks of the brains found in scorpions and spiders: Three clusters of nerve cells known as ganglia fused together as a brain also fused with some of the animal's body ganglia. This differs from crustaceans where ganglia are further apart and connected by long nerves, like the rungs of a rope ladder.
Other diagnostic features include the forward position of the gut opening in the brain and the arrangement of optic centers outside and inside the brain supplied by two pairs of eyes, just like in horseshoe crabs.
Horseshoe crabs survive as "living fossils" to this day, as residents near the Great Lakes know from the annual swarms. This fossil resembles modern chelicerates, one of the largest subphyla of arthropods, including horseshoe crabs, scorpions, spiders, mites, harvestmen, and ticks. Live Science adds, "The discovery of a fossilized brain in the preserved remains of an extinct 'mega-clawed' creature has revealed an ancient nervous system that is remarkably similar to that of modern-day spiders and scorpions."
Since crustaceans and chelicerates have both been found in the early Cambrian, Darwinian evolutionists are forced to postulate an unknown ancestor further back in time: "They had to come from somewhere," Strausfeld remarks. "Now the search is on." That sounds like the same challenge Charles Darwin gave fossil hunters 154 years ago to find the ancestors of the Cambrian animals.
The difficulty? It requires many different tissue types and interconnected systems to operate a complex animal like Alalcomenaeus, with its body segments, eyes, claws, mouth parts, gut and nervous system with a brain, to say nothing of coordinating the developmental programs that build these systems from a single cell. That is the major problem that Stephen Meyer emphasizes in Darwin's Doubt: where does the information come from to build complex body plans with hierarchical levels of organization?
Slamming a space rock at the Earth is hardly a plausible source of information. Meyer has been answering in detail the most serious and scholarly critique of his book, by Charles Marshall, refuting Marshall's criticisms point by point. Meanwhile the proposed alternative explanations for the Cambrian event keep coming, bearing increasingly the marks of desperation.
Evolution News & Views
It's surely not a coincidence that this season in science-journal publishing we've seen a variety of attempts to solve the enigma that Stephen Meyer describes in his new book, Darwin's Doubt. The problem, of course, is how to account for the geologically sudden eruption of complex new life forms in the Cambrian explosion. Meyer argues that the best explanation is intelligent design.
The orthodox materialist camp in mainstream science remains in full denial mode. They can't stomach the proposal of ID, but neither can they for the most part bring themselves to answer Meyer by name, or even admit there's a controversy on the subject. Charles Marshall, reviewing the book in Science, is the honorable exception. So we get what look like stealth responses to Meyer's book that claim to have figured out the Cambrian puzzle without telling you what the urgency for doing so really is, thus evading the task of responding to Meyer directly. (See David Klinghoffer's review of the reviewers of Darwin's Doubt, "A Taxonomy of Evasion.")
Probably the most hopeless solution so far ascribes some of the creative power to a blast in the ocean by a space impact. This supposedly helped "set the stage" for the rapid proliferation of new animal forms. When we examine the complexity of a single Cambrian fossil, though, such a notion, like the others on offer, leaves all the important questions unanswered.
To his credit, Grant M. Young, the author of the proposal, is somewhat modest in the way he formulates his idea. His paper in GSA Today is primarily concerned with looking for evidence of a "very large marine impact" prior to the Ediacaran Period that sent vast quantities of water and oxygen into the atmosphere, changed the obliquity of Earth's spin axis, and altered sea levels. The aftermath of that catastrophe, he speculates, played a role in the Cambrian explosion -- but a "crucial" one.
Attendant unprecedented environmental reorganization may have played a crucial role in the emergence of complex life forms. (Emphasis added.)
That's all Young had to say about it, but the suggestion was enough for NASA's Astrobiology Magazine to jump on it with a breathless headline: "Did a Huge Impact Lead to the Cambrian Explosion?" Author Johnny Bontemps catapulted that tease into the notion that "The ensuing environmental re-organization would have then set the stage for the emergence of complex life." Bontemps is correct about one thing:
These events marked the beginning of another drastic event known as the Cambrian explosion. Animal life on Earth suddenly blossomed, with all of the major groups of animals alive today making their first appearance.
Let's take a look at just one of the Cambrian animals, as seen in an exquisitely preserved new fossil from the Chengjiang strata in China, where so many beautiful fossils have been found (examples are shown in the Illustra film Darwin's Dilemma). The new fossil, Alalcomenaeus, published by Nature, was furnished with multiple claws like other Cambrian arthropods, but was so well preserved its nervous system could be outlined in detail. Even though it is dated from the early Cambrian at 520 million years old, it already had the nerves of modern spiders. Co-author Nick Strausfeld explains:
"We now know that the megacheirans had central nervous systems very similar to today's horseshoe crabs and scorpions," said Strausfeld, the senior author of the study and a Regents' Professor in the UA's Department of Neuroscience. "This means the ancestors of spiders and their kin lived side by side with the ancestors of crustaceans in the Lower Cambrian."'
Though tiny (about an inch long), its nervous system must have been fairly advanced, because the elongated creature was capable of swimming or crawling or both. In addition to about a dozen body segments with jointed appendages, it had a "pair of long, scissor-like appendages attached to the head, most likely for grasping or sensory purposes." It also had two pairs of eyes.
Iron deposits selectively accumulated in the nerve cells, allowing the research team to reconstruct the highly organized brain and nervous system. After processing with CT scans and iron scans, "out popped this beautiful nervous system in startling detail."
Comparing the outline of the fossil nervous system to nervous systems of horseshoe crabs and scorpions left no doubt that 520-million-year-old Alalcomenaeus was a member of the chelicerates.
Specifically, the fossil shows the typical hallmarks of the brains found in scorpions and spiders: Three clusters of nerve cells known as ganglia fused together as a brain also fused with some of the animal's body ganglia. This differs from crustaceans where ganglia are further apart and connected by long nerves, like the rungs of a rope ladder.
Other diagnostic features include the forward position of the gut opening in the brain and the arrangement of optic centers outside and inside the brain supplied by two pairs of eyes, just like in horseshoe crabs.
Horseshoe crabs survive as "living fossils" to this day, as residents near the Great Lakes know from the annual swarms. This fossil resembles modern chelicerates, one of the largest subphyla of arthropods, including horseshoe crabs, scorpions, spiders, mites, harvestmen, and ticks. Live Science adds, "The discovery of a fossilized brain in the preserved remains of an extinct 'mega-clawed' creature has revealed an ancient nervous system that is remarkably similar to that of modern-day spiders and scorpions."
Since crustaceans and chelicerates have both been found in the early Cambrian, Darwinian evolutionists are forced to postulate an unknown ancestor further back in time: "They had to come from somewhere," Strausfeld remarks. "Now the search is on." That sounds like the same challenge Charles Darwin gave fossil hunters 154 years ago to find the ancestors of the Cambrian animals.
The difficulty? It requires many different tissue types and interconnected systems to operate a complex animal like Alalcomenaeus, with its body segments, eyes, claws, mouth parts, gut and nervous system with a brain, to say nothing of coordinating the developmental programs that build these systems from a single cell. That is the major problem that Stephen Meyer emphasizes in Darwin's Doubt: where does the information come from to build complex body plans with hierarchical levels of organization?
Slamming a space rock at the Earth is hardly a plausible source of information. Meyer has been answering in detail the most serious and scholarly critique of his book, by Charles Marshall, refuting Marshall's criticisms point by point. Meanwhile the proposed alternative explanations for the Cambrian event keep coming, bearing increasingly the marks of desperation.
When the original technologist holds court.
Intelligent Designs in Nature Make Engineers Envious
Evolution News & Views
We've reported numerous times about the vibrant field of biomimetics: the science of imitating nature. There are whole departments at universities dedicated to this. There are journals like Bioinspiration and Biomimetics, the Journal of Biomimetics, Biomaterials, and Tissue Engineering, and Frontiers in Bioengineering and Biotechnology that regularly report on it. Entrepreneurs have started companies to build products mimicking nature. Biomimetics is on a roll. Here are a few of scientists' latest attempts to copy nature's designs. They wouldn't try so hard if the designs weren't intelligent.
Flight on the Small Scale
A news item from the University of Alabama shows Dr. Amy Lang studiously gazing at a Monarch butterfly on the wing. She has reason to stay focused. She just got a $280,000 grant from the National Science Foundation to study the scales on butterfly wings to find ways to improve flight aerodynamics for MAVs (micro area vehicles).
Butterflies don't require the scales to fly, but Dr. Lang knows they help the insects fly better. "The butterfly scales are beautifully arranged on the wing, and how the scales are arranged is where the aerodynamic benefit comes in," she says. This "unique micro pattern ... reduces drag and likely increases thrust and lift during flapping and glided flight." When the scales are removed, the butterfly has to flap its wings 10 percent more to maintain the same flight.
If you've seen Metamorphosis: The Beauty and Design of Butterflies you may recall the striking electron micrographs of the tiny scales, each less than a tenth of a millimeter in width, arranged like shingles on a roof. According to Dr. Lang, there's a reason: "the scales stick up slightly, trapping a ball of air under the scale and allowing air to flow smoothly over it." Her team wants to understand the physics behind this design before trying to model it on artificial flyers.
The article assumes butterflies happened upon these "evolutionary adaptations" by blind, unguided processes: "The scales covering butterfly and moth wings represent about 190 million years of natural selection for insect flight efficiency." Metamorphosis refutes that notion, but what matters in the story is not evolution, but design -- here is a natural design that the NSF feels is worth at least $280,000 to try to imitate. (Dr. Lang also "works with shark scales" in her "bio-designed engineering" lab.)
It's a Bird; It's a Plane; It's Robo Raven
You met nano-hummingbird in Illustra's film Flight: The Genius of Birds. Now here's Robo Raven, a flying drone built at the University of Maryland -- the first Micro Air Vehicle (MAV) using flapping flight. We've noted this briefly before. A video clip shows how Robo Raven III uses sunlight from solar panels built into its wings to charge batteries.
Nature, as usual, does it better. The Robo Raven III can only gather about 30 watts -- an order of magnitude too low to stay aloft indefinitely, IEEE Spectrum says, pointing out that real ravens get "crazy high power density" from meat. On his blog, Professor S. K. Gupta of the UMass design team compares performance between the two, noting that his invention also mimics another natural technology -- solar energy collection by plants:
However, nature has a significant edge over engineered system in other areas. For example, one gram of meat stores 20 times more energy than one gram of the current battery technology. So in terms of the energy density, we engineers have a lot of catching up to do. In nature, solar energy collection devices (e.g., trees) are not on-board ravens. Hence, ravens ultimately utilize a large collection area to gather energy into highly a dense storage source (e.g., meat), giving them a much longer range and better endurance than Robo Raven III. (Emphasis added.)
While Gupta notes that direct solar energy conversion to mechanical energy would be about an order of magnitude more efficient than an animal's metabolic pathway, "We still need to make significant improvements in solar cell efficiency and battery energy density to replicate the endurance of real ravens in Robo Raven III," he confesses. Real ravens also use that metabolism to perform many functions besides flapping flight -- including reproduction, navigation, and the operation of multiple senses. (Living birds can also fly at night.)
Short Takes
Solar power: "Inspired by nature: To maximise the efficiency of solar cells of the future, physicists are taking a leaf out of nature's book" (Cavendish Laboratory, University of Cambridge).
Robotics: "Amber 2 robot walks with a human gait." Why is that good? "People are able to walk so smoothly because of the seamless interaction between the muscles, bone, ligaments, etc. in the legs, ankles and feet ... Getting a robot to walk like us means not just building legs, ankles or feet like ours, it means programming them all to work together in way that is graceful when the robot walks, and that appears to be where the Amber 2 team is headed" (PhysOrg reporting on work at Texas A&M).
Sonar: An engineer was watching a nature show and wondered why dolphins blew bubbles to trap fish, when it would seemingly mess up their sonar signals. He found that the dolphins use two click frequencies that allow them to distinguish between the bubbles and fish. This "inspired the development of a cheap, coin-sized radar gadget that can sense hidden electronics" (New Scientist, reporting on work at University of Southampton).
Does Darwin-Talk Add Value?
Occasionally, news stories like these attribute the designs in question to natural selection. "Through billions of years of evolution, life on Earth has found intricate solutions to many of the problems scientists are currently grappling with," the item from Cambridge says. But then, most of the story marvels at the intricate design that blind nature supposedly arrived at.
Biology has evolved phenomenally subtle systems to funnel light energy around and channel it to the right places. It has also become incredibly good at building tiny devices that work with high efficiency, and at replicating them millions of times.
Similarly, New Scientist ends its biodesign story with: "Evolution has once again sparked ideas for remarkable innovation."
The Darwin language gets to be as annoying as those pop-up ads on the Internet that have nothing to do with the story. The focus is on design -- "intricate solutions" so good, they occupy the best minds in the world's finest academic institutions; designs so attractive, they are worth six-figure government grants to imitate.
You wouldn't want to insult bioengineers with the suggestion they are mimicking blind, unguided processes in their work. No, from our uniform experience, a good design comes from a good mind.
Evolution News & Views
We've reported numerous times about the vibrant field of biomimetics: the science of imitating nature. There are whole departments at universities dedicated to this. There are journals like Bioinspiration and Biomimetics, the Journal of Biomimetics, Biomaterials, and Tissue Engineering, and Frontiers in Bioengineering and Biotechnology that regularly report on it. Entrepreneurs have started companies to build products mimicking nature. Biomimetics is on a roll. Here are a few of scientists' latest attempts to copy nature's designs. They wouldn't try so hard if the designs weren't intelligent.
Flight on the Small Scale
A news item from the University of Alabama shows Dr. Amy Lang studiously gazing at a Monarch butterfly on the wing. She has reason to stay focused. She just got a $280,000 grant from the National Science Foundation to study the scales on butterfly wings to find ways to improve flight aerodynamics for MAVs (micro area vehicles).
Butterflies don't require the scales to fly, but Dr. Lang knows they help the insects fly better. "The butterfly scales are beautifully arranged on the wing, and how the scales are arranged is where the aerodynamic benefit comes in," she says. This "unique micro pattern ... reduces drag and likely increases thrust and lift during flapping and glided flight." When the scales are removed, the butterfly has to flap its wings 10 percent more to maintain the same flight.
If you've seen Metamorphosis: The Beauty and Design of Butterflies you may recall the striking electron micrographs of the tiny scales, each less than a tenth of a millimeter in width, arranged like shingles on a roof. According to Dr. Lang, there's a reason: "the scales stick up slightly, trapping a ball of air under the scale and allowing air to flow smoothly over it." Her team wants to understand the physics behind this design before trying to model it on artificial flyers.
The article assumes butterflies happened upon these "evolutionary adaptations" by blind, unguided processes: "The scales covering butterfly and moth wings represent about 190 million years of natural selection for insect flight efficiency." Metamorphosis refutes that notion, but what matters in the story is not evolution, but design -- here is a natural design that the NSF feels is worth at least $280,000 to try to imitate. (Dr. Lang also "works with shark scales" in her "bio-designed engineering" lab.)
It's a Bird; It's a Plane; It's Robo Raven
You met nano-hummingbird in Illustra's film Flight: The Genius of Birds. Now here's Robo Raven, a flying drone built at the University of Maryland -- the first Micro Air Vehicle (MAV) using flapping flight. We've noted this briefly before. A video clip shows how Robo Raven III uses sunlight from solar panels built into its wings to charge batteries.
Nature, as usual, does it better. The Robo Raven III can only gather about 30 watts -- an order of magnitude too low to stay aloft indefinitely, IEEE Spectrum says, pointing out that real ravens get "crazy high power density" from meat. On his blog, Professor S. K. Gupta of the UMass design team compares performance between the two, noting that his invention also mimics another natural technology -- solar energy collection by plants:
However, nature has a significant edge over engineered system in other areas. For example, one gram of meat stores 20 times more energy than one gram of the current battery technology. So in terms of the energy density, we engineers have a lot of catching up to do. In nature, solar energy collection devices (e.g., trees) are not on-board ravens. Hence, ravens ultimately utilize a large collection area to gather energy into highly a dense storage source (e.g., meat), giving them a much longer range and better endurance than Robo Raven III. (Emphasis added.)
While Gupta notes that direct solar energy conversion to mechanical energy would be about an order of magnitude more efficient than an animal's metabolic pathway, "We still need to make significant improvements in solar cell efficiency and battery energy density to replicate the endurance of real ravens in Robo Raven III," he confesses. Real ravens also use that metabolism to perform many functions besides flapping flight -- including reproduction, navigation, and the operation of multiple senses. (Living birds can also fly at night.)
Short Takes
Solar power: "Inspired by nature: To maximise the efficiency of solar cells of the future, physicists are taking a leaf out of nature's book" (Cavendish Laboratory, University of Cambridge).
Robotics: "Amber 2 robot walks with a human gait." Why is that good? "People are able to walk so smoothly because of the seamless interaction between the muscles, bone, ligaments, etc. in the legs, ankles and feet ... Getting a robot to walk like us means not just building legs, ankles or feet like ours, it means programming them all to work together in way that is graceful when the robot walks, and that appears to be where the Amber 2 team is headed" (PhysOrg reporting on work at Texas A&M).
Sonar: An engineer was watching a nature show and wondered why dolphins blew bubbles to trap fish, when it would seemingly mess up their sonar signals. He found that the dolphins use two click frequencies that allow them to distinguish between the bubbles and fish. This "inspired the development of a cheap, coin-sized radar gadget that can sense hidden electronics" (New Scientist, reporting on work at University of Southampton).
Does Darwin-Talk Add Value?
Occasionally, news stories like these attribute the designs in question to natural selection. "Through billions of years of evolution, life on Earth has found intricate solutions to many of the problems scientists are currently grappling with," the item from Cambridge says. But then, most of the story marvels at the intricate design that blind nature supposedly arrived at.
Biology has evolved phenomenally subtle systems to funnel light energy around and channel it to the right places. It has also become incredibly good at building tiny devices that work with high efficiency, and at replicating them millions of times.
Similarly, New Scientist ends its biodesign story with: "Evolution has once again sparked ideas for remarkable innovation."
The Darwin language gets to be as annoying as those pop-up ads on the Internet that have nothing to do with the story. The focus is on design -- "intricate solutions" so good, they occupy the best minds in the world's finest academic institutions; designs so attractive, they are worth six-figure government grants to imitate.
You wouldn't want to insult bioengineers with the suggestion they are mimicking blind, unguided processes in their work. No, from our uniform experience, a good design comes from a good mind.
Subscribe to:
Posts (Atom)