Yet another Darwinian bedtime story?

Test Your Evolutionary Storytelling Skills
David Klinghoffer | @d_klinghoffer

Ever notice that some older people sleep less and sometimes more fitfully than younger people? Sure you did. On the other hand, you’ve probably also known old people who sleep in and some middle aged and younger people who complain of sleep problems. I could introduce you to representatives of all these groups from my own family.

Any phenomenon in human life is a suitable subject for evolutionary storytelling, and telling stories about the past is what a team of scientists set out to do. Traveling to Africa, they fitted members of the Hadza people of Tanzania with actigraph devices to monitor their sleep.

The subjects of the experiment are hunter-gatherers who slumber outdoors in small groups in the wild. The study confirmed what you would have guessed: It’s pretty typical for older people to doze and wake and doze and wake more than young people. They wake up earlier too. From Science Daily:

As part of the study, 33 healthy men and women aged 20 to 60 agreed to wear a small watch-like device on their wrists for 20 days, that recorded their nighttime movements from one minute to the next.

Hadza sleep patterns were rarely in sync, the researchers found. On average, the participants went to bed shortly after 10 p.m. and woke up around 7 a.m. But some tended to retire as early as 8:00 p.m. and wake up by 6 a.m., while others stayed up past 11 p.m. and snoozed until after 8 a.m.

In between, they roused from slumber several times during the night, tossing and turning or getting up to smoke, tend to a crying baby, or relieve themselves before nodding off again.

As a result, moments when everyone was out cold at once were rare. Out of more than 220 total hours of observation, the researchers were surprised to find only 18 minutes when all adults were sound asleep simultaneously. On average, more than a third of the group was alert, or dozing very lightly, at any given time.

They always have to put in that they were “surprised.” Otherwise why bother with the study? Anyway, that’s really all you need to know. Now take the challenge: With these facts, tell an imaginative story about human evolution. Think about it for a moment and if you want, write down your answer on some scratch paper.

Here’s a hint: Did you follow Monday’s news story  from Colorado about a 19-year-old camp counselor, sleeping in the open by a lake, who awoke to find a bear sharpening its teeth on his skull? The counselor was camping out with four younger campers. He survived, despite serious lacerations.

OK, what did you come up with? If it’s the following, I wouldn’t be surprised: Long ago, ancient humans slept in the open, like these African hunter-gatherers. Having older people with you improves the likelihood that if hostile animals or people creep up, then someone will be awake to sound the alarm. Evolution selected for this feature. End of story.

We read on:

The findings may help explain why Hadza generally don’t post sentinels to keep watch throughout the night — they don’t need to, the researchers say. Their natural variation in sleep patterns, coupled with light or restless sleep in older adults, is enough to ensure that at least one person is on guard at all times.

…

[The scientists] call their theory the “poorly sleeping grandparent hypothesis.” The basic idea is that, for much of human history, living and sleeping in mixed-age groups of people with different sleep habits helped our ancestors keep a watchful eye and make it through the night.

“Any time you have a mixed-age group population, some go to bed early, some later,” Nunn said. “If you’re older you’re more of a morning lark. If you’re younger you’re more of a night owl.”

If the Colorado bear attack victim had been camping out with his grandparents, it’s possible one of them might have noticed the bear before it could get too close. Same thing if the group had posted a lookout, as I imagine some campers in the area, worried about bears, may do tonight. It’s genuinely surprising the Hadza don’t assign anyone to act as a sentinel. This would make me nervous if I were one of them, and it might even interfere with sleep.

In any event, is this science or storytelling? From the Abstract of the study:

Chronotype variation and human sleep architecture (including nocturnal awakenings) in modern populations may therefore represent a legacy of natural selection acting in the past to reduce the dangers of sleep.

It may or it may not. There are physiological reasons that sleep varies with age. Babies also wake up periodically during the night, while many teenagers have a hard time getting up in the morning. The story about ancient human lifestyles is interesting, but attributing “human sleep architecture” to natural selection is merely what chemist and National Academy of Sciences member Philip Skell, writing in The Scientist, dismissed as evolutionary “narrative gloss.”

Besides needing to say they are “surprised” by the results, the researchers, who published in their work in the  Proceedings of the Royal Society B, are expected to come up with a reason why the findings are of practical usefulness. They oblige:

“A lot of older people go to doctors complaining that they wake up early and can’t get back to sleep,” [Duke University anthropologist Charlie] Nunn said.

“But maybe there’s nothing wrong with them. Maybe some of the medical issues we have today could be explained not as disorders, but as a relic of an evolutionary past in which they were beneficial,” said Nunn.

Some older people are bothered by their irregular sleep patterns. Others aren’t bothered by it. It’s the ones who are bothered that go to the doctor to complain. For them, it is hard to see what help a physician could offer, that would make a difference, by telling an evolutionary bedtime story.

And yet even more on the real world's anti-Darwinian bias.

Math, Computers, and Evolution: Robert Marks on Searches and Artificial Intelligence
Evolution News | @DiscoveryCSC

On a new episode of ID the Future, CSC Director of Communications Rob Crowther talks with Robert Marks, Distinguished Professor of Electrical and Computer Engineering at Baylor University, about Marks’s new book, Introduction to Evolutionary Informatics, which makes an important but esoteric-sounding field accessible to the general reader.

Dr. Marks talks about how he and William Dembski originally connected as researchers, and began working on the subject in 2007, how intelligent design can inform thinking on artificial intelligence, and what a “search for a search” means in evolutionary terms. Download the podcast here, or listen to it here.

Get your copy of Introduction to Evolutionary Informatics  by Winston Ewert, William Dembski, and Robert Marks! More information is at the Evolutionary Informatics Lab’s website,  evoinfo.org — that’s evo info, as Dr. Marks helpfully explains, not evil info. Just so there’s no confusion.

The Royal Society on Darwinism's "explanatory deficits"

Why the Royal Society Meeting Mattered, in a Nutshell

Evolution News | @DiscoveryCSC

We devoted  considerable attention to last month’s Royal Society meeting in London. Otherwise, the three-day conference on “New Trends in Evolutionary Biology” was kept rather quiet in the media.

Oh, there were a few reports. Writing for the Huffington Post,  science journalist Suzan Mazur complained of a lack of momentousness: “[J]ust what was the point of attracting a distinguished international gathering if the speakers had little new science to present? Why waste everyone’s time and money?” On the other hand, a write-up in The Atlantic by Carl Zimmer acknowledged a sense of strain between rival cliques of evolutionists: “Both sides offered their arguments and critiques in a civil way, but sometimes you could sense the tension in the room — the punctuations of tsk-tsks, eye-rolling, and partisan bursts of applause.”

Mild drama notwithstanding, why should anyone care about this meeting?

Despite the muffled coverage, the meeting was still significant in a number of ways. First, remember that the Royal Society is arguably the world’s most august scientific body. Its founders included Robert Boyle and it was later headed for 24 years (1703-1727) by Isaac Newton — a fact that is hard to forget when they have his death mask on prominent display in a glass case. Portraits of Boyle and Newton on the walls look down from above. The historical connections lent a certain weight by themselves to the proceedings.

That such a thoroughly mainstream scientific organization should now at last acknowledge problems with the received neo-Darwinian theory of evolution is also obviously notable. Indeed, from our point of view, though presenters  ignored, dismissed, or mocked ID, not realizing the number of design-friendly scientists in the audience, the proceedings confirmed something ID advocates, including Stephen Meyer and others, have been saying for years.

Consider, for example, Meyer’s provocative claim in the Prologue to Darwin’s Doubt:

The technical literature in biology is now replete with world-class biologists routinely expressing doubts about various aspects of neo-Darwinian theory, and especially about its central tenet, namely the alleged creative power of the natural selection and mutation mechanism.

Nevertheless, popular defenses of the theory continue apace, rarely if ever acknowledging the growing body of critical scientific opinion about the standing of the theory. Rarely has there been such a great disparity between the popular perception of a theory and its actual standing in the relevant peer-reviewed science literature.

The opening presentation at the Royal Society conference by one of those world-class biologists, Austrian evolutionary theorist Gerd Müller, underscored exactly Meyer’s point. Müller opened the meeting by discussing several of the fundamental “explanatory deficits” of “the modern synthesis,” that is, textbook neo-Darwinian theory. (Discovery Institute’s Paul Nelson recounted Müller’s remarks here, on which in part we base the following.) According to Müller, the as yet unsolved problems include those of explaining:

Phenotypic complexity (the origin of eyes, ears, body plans, i.e., the anatomical and structural features of living creatures);

Phenotypic novelty, i.e., the origin of new forms throughout the history of life (for example, the mammalian radiation some 66 million years ago, in which the major orders of mammals, such as cetaceans, bats, carnivores, enter the fossil record, or even more dramatically, the Cambrian explosion, with most animal body plans appearing more or less without antecedents); and finally

Non-gradual forms or modes of transition, where you see abrupt discontinuities in the fossil record between different types.

As Müller has explained in previously published work (with Stuart Newman), although “the neo-Darwinian paradigm still represents the central explanatory framework of evolution, as represented by recent textbooks” it “has no theory of the generative.”1 In other words, the neo-Darwinian mechanism of mutation and natural selection lacks the creative power to generate the novel anatomical traits and forms of life that have arisen during the history of life. Yet, as Müller noted, neo-Darwinian theory continues to be presented to the public via textbooks as the canonical understanding of how new living forms arose — reflecting precisely the tension between the perceived, and actual, status of the theory that Meyer described in Darwin’s Doubt.

Yet, the most important lesson of the Royal Society conference lies not in its vindication of claims that our scientists have made, gratifying as that might be to us, but rather in defining the current problems and state of research in the field. The conference did an excellent job of defining the problems that evolutionary theory has failed to solve, but it offered little, if anything, by way of new solutions to those longstanding fundamental problems.

Much of the conference subsequent to Müller’s talk did discuss various other proposed evolutionary mechanisms. Indeed, the prime movers in the Royal Society event, Müller, along with James Shapiro, Denis Noble, and Eva Jablonka — the “Third Way of Evolution” crowd — have proposed repairing the explanatory deficits of the modern synthesis by highlighting evolutionary mechanisms other than random mutation and natural selection. Much debate at the conference centered around the question of whether these new mechanisms could be incorporated into the basic population genetics framework of neo-Darwinism, thus making possible a new “extended” evolutionary synthesis, or whether the emphasis on new mechanisms of evolutionary change represented a radical, and theoretically incommensurable, break with established theory. This largely semantic, or classificatory, issue obscured a deeper question that few, if any, of the presentations confronted head on: the issue of the origin of genuine phenotypic novelty — the problem that Müller described in his opening talk.

Indeed, by the end of Day 3 of the meeting, it seemed clear to many of our scientists, and others in attendance with whom they talked, that the puzzle of life’s novelties remained unsolved — if, indeed, it had been addressed at all. As a prominent German paleontologist in the crowd concluded, “All elements of the Extended Synthesis [as discussed at the conference] fail to offer adequate explanations for the crucial explanatory deficits of the Modern Synthesis (aka neo-Darwinism) that were explicitly highlighted in the first talk of the meeting by Gerd Müller.”

In Darwin’s Doubt, for example, Meyer emphasized the obvious importance of genetic and other (i.e., epigenetic) types of information to building novel phenotypic traits and forms life. The new mechanisms offered by the critics of neo-Darwinism at the conference — whether treated as part of an extended neo-Darwinian synthesis or as the basis of a fundamentally new theory of evolution — did not attempt to explain how the information necessary to generating genuine novelty might have arisen. Instead, the mechanisms that were discussed produce at best minor microevolutionary changes, such as changes in wing coloration of butterflies or the celebrated polymorphisms of stickleback fish.

Moreover, the mechanisms that were discussed — niche construction, phenotypic plasticity, natural genetic engineering, and so on — either presupposed the prior existence of the biological information necessary to generate novelty, or they did not address the mystery of the origin of that information (and morphological novelty) at all. (Not all the mechanisms addressed were necessarily new, by the way. Niche construction and phenotypic plasticity have been around for a long time.)

Complex behaviors such as nest-building by birds, or dam construction by beavers, represent examples of niche construction  in which some organisms themselves demonstrate the capacity to alter their environment in ways that may affect the adaptation of subsequent generations to the environment. Yet no advocate of niche construction at the meeting explained how the capacity for such complex behaviors arose de novo in ancestral populations, as they must have done if the naturalistic evolutionary story is true.

Rather, these complex behaviors were taken as givens, leaving the critical question of their origins more or less untouched. While there is abundant evidence that animals can learn and transmit new behaviors to their offspring —  crows in Japan for instance, have learned how to use automobile traffic to crack open nuts — all such evidence presupposes the prior existence of specific functional capacities enabling observation, learning, and the like. The evolutionary accounts of niche construction theory therefore collide repeatedly with a brick wall marked “ORIGINAL COMPLEX FUNCTIONAL CAPACITY REQUIRED HERE” — without, or beyond which, there would simply be nothing interesting to observe.

Jim Shapiro’s talk, clearly one of the most interesting of the conference, highlighted this difficulty in its most fundamental form. Shapiro presented fascinating evidence showing, contra neo-Darwinism, the non-random nature of many mutational processes — processes that allow organisms to respond to various environmental challenges or stresses. The evidence he presented suggests that many organisms possess a kind of pre-programmed adaptive capacity — a capacity that Shapiro has elsewhere described as operating under “algorithmic control.” Yet, neither Shapiro, nor anyone else at the conference, attempted to explain how the information inherent in such algorithmic control or pre-programmed capacity might have originated.

This same “explanatory deficiency” was evident in the discussions of the other mechanisms, though we won’t attempt to demonstrate that exhaustively here. We would direct readers, however, to Chapters 15 and 16 of Darwin’s Doubt, where Meyer highlighted the way in which, not just neo-Darwinism, but also newer evolutionary mechanisms, including many discussed at the conference, fail to solve the question of the origin of information necessary to generate novelty. In those chapters, he reviewed a range of proposed fixes to the Modern Synthesis. He acknowledged and described the various advantages that many of these proposals have over neo-Darwinism, but also carefully explained why each of these mechanisms falls short as an explanation for the origin of the biological information necessary to build novel structures and forms of animal life. He quoted paleontologist Graham Budd who has observed: “When the public thinks about evolution, they think about [things like] the origin of wings….But these are things that evolutionary theory has told us little about.”

Many fascinating talks at the Royal Society conference described a number of evolutionary mechanisms that have been given short shrift by the neo-Darwinian establishment. Unfortunately, however, the conference will be remembered, as Suzan Mazur intimated in her coverage, for its failure to offer anything new. In particular, in our judgment, it failed to offer anything new that could help remedy the main “explanatory deficit” of the neo-Darwinian synthesis — its inability to account for the origin of phenotypic novelty and especially, the genetic and epigenetic information necessary to produce it. These are still problems that evolutionary theory tells us little about.

Notes:

(1) Gerd Müller and Stuart Newman, On the Origin of Organismal Form (Cambridge, MA: MIT Press, 2003), p.7.

Nature's navigators v. Darwin.

Getting Around: Animal Migrations Exceed Evolutionary Expectations
Evolution News | @DiscoveryCSC

Why not stay put? In evolutionary terms, that seems an easier option for migrating animals. The evolutionist might argue that animals need to follow the food supply, but since natural selection is supposed to be so clever, why not evolve hibernation or a smaller stomach? Sure, animals need to follow the temperature, but why not just evolve thicker fur or feathers like snowy owls?

For every spectacular case of animal migration, biologists can find other animals that stay put in the cold, like the snowshoe hare, or go into hibernation, like bears or insect pupae, surviving the cold months of winter. Plants stay put whether in the Arctic or the desert. Why should animals travel thousands of miles through precarious weather or trackless seas? It doesn’t make evolutionary sense. Let’s look at some recent findings about animal migration.

Fish: European Eels

   

In Evolution: Evolution: Still a Theory in Crisis, Michael Denton describes the amazing life cycle of European eels. It’s an example of “baroque” design in the animal world, he argues, totally inexplicable by any kind of “selective pressure” that might be alleged to explain it. Since we last wrote about eels in October, more has been learned about the spectacular migration of these freshwater fish out to the salty ocean. We had asked, “Are eels equipped with magnetosensing, like salmon, sea turtles, and Monarch butterflies?”

The answer is, “yes” — researchers at the University of Miami  have found.

Scientists are closer to unraveling the long-standing mystery of how tiny glass eel larvae, which begin their lives as hatchlings in the Sargasso Sea, know when and where to “hop off” the Gulf Stream toward European coastlines to live out their adult lives in coastal estuaries.

In a new study by the University of Miami (UM)’s Rosenstiel School of Marine and Atmospheric Science in collaboration with the Norwegian Institute of Marine Research’s Austevoll Research Station found that these glass eels (Anguilla anguilla) can sense Earth’s magnetic field and use it like a compass controlled by an internal “biological” clock to orient themselves towards the coast. 

Notice that two senses cooperate in this skill: the ability to sense Earth’s magnetic field, and a biological clock to know when to change direction in relation to that field. The discoveries were made by monitoring eel orientations in a test facility where the ambient magnetism could be controlled.

“It is incredible that these small transparent glass eels can detect the earth’s magnetic field. The use of a magnetic compass could be a key component underlying the amazing migration of these animals,” said Cresci, the study’s lead author. “It is also the first observation of glass eels keeping a compass as they swim in shelf waters, and that alone is an exciting discovery.”

Not surprisingly, the paper in Science Advances  doesn’t speculate about how this ability might have evolved. They simply state the design-friendly facts:

Glass eels have a magnetic compass, and their orientation abilities appear to be linked to the tidal phase. This is preliminary evidence that magnetic compass–guided movement behavior could be tuned by an endogenous rhythm in the early life stages of a fish. This compass-guided movement, regulated by an endogenous rhythm, may be present in many migratory species.

Speaking of timing, it appears that salmon like to migrate in groups. Phys.org says that even when conditions are stable, observers don’t see sockeye salmon cueing off environmental conditions individually. Instead, pulses of fish are seen migrating together, perhaps for the added protection of a group.

Birds: Golden Eagles and Shearwaters

Humans aren’t the only beings familiar with a generation gap. Golden eagles have it, too. Bird watchers with the American Ornithological Society found that young and old eagles have “counterintuitive” migration habits. Science Daily  explains the findings:

Migration is tough, and birds do everything they can to optimize it. How do factors like weather and experience affect the strategies they choose? A new study from The Auk: Ornithological Advances shows that older, more experienced Golden Eagles actually migrate in poorer weather conditions and cover less ground than their younger counterparts, but for a good reason — they’re timing their efforts around raising the next generation of eagles.

The authors give a tip of the hat to evolution, saying, “Because of the costs of migration, there is selective pressure to capitalize on variation in weather to optimize migratory performance.” But as we said earlier, selection pressure should work to make the eagles stay put, not make them go through such hardships to reproduce.

The shearwater is a migratory bird that carries with it a travel journal of sorts. Richard Banati, a nuclear physicist in Australia, decided to take a look at the feathers with X-ray fluorescence microscopy, and found something unexpected: bands of zinc, calcium, bromine, copper and iron. He believes these provide clues to this species’ migratory habits as they fly a figure-8 path between the coasts of Siberia, Japan, and Tasmania on a 60,000-km route over open ocean. Writing in  The Conversation, he says:

Like the annual growth rings of trees, birds’ feathers lay down growth bars during their moult. (Moulting is the process of shedding old feathers, making way for new ones to grow.)

While bars simply show growth, the patterns of chemical elements tell us about the bird’s life during the growth period of the feather. They can indicate environmental exposures in a bird population, perhaps before impacts such as illness and death are clear….

The chemistry of feathers might become a tool for watching our environment.

Mammals: Whales

Imagine the surprise of boaters when a blue whale overturned their sightseeing boat off the coast of San Diego (see the video at BBC News). Is this sport to the giant beasts, the largest animals that have ever lived, something like tipping cows to farm boys? Nobody knows what was going through this whale’s mind, but we do know that whales are also master migrators, covering thousands of miles through clear and murky ocean routes. Remember Isabela, the blue whale that clocked a record 5,200 kilometers?

The World Wildlife Fund has been having fun with “whale cams” attached to humpback whales and minke whales,  Live Science reports. This is giving scientists unprecedented views of the social lives and feeding habits of these animals. The whale cams show that migration can be vertical as well as horizontal: “whales will range from rolling lunges near the surface to dives up to 1,148 feet (250 meters) deep to eat krill (small crustaceans), their main food source.”

Another team publishing in  Science Advances found a novel technique to monitor humpback feeding habits: radiocarbon. “While the whales mostly relied on Antarctic-derived energy stores during their annual migration, there was some evidence of feeding within temperate zone waters in some individuals.” Differences in radiocarbon, measured in the whales’ baleen plates and skin, apparently come from different abundances of radiocarbon between polar and temperate waters. The study provided the first evidence that some individuals were supplementing their diet with trips into geographically distant food webs.

Amazing Daily Commuters

Daily migrations can be as interesting as annual migrations. The average human commuter drives about 5 to 13 miles per day, according to National Geographic. Compare that with blue herons, which fly up to 20 miles per day in search of food. A tropical Atlantic fish called the French grunt swims about a kilometer per day. Then there are the golden jellyfish of Palau, which follow the sun each day across a lake to support their photosynthetic algae partners.

One of the most amazing daily commuters, though, is also the smallest: plankton. Reporter Liz Langley calls it the largest vertical migration of its kind, in terms of biomass. An embedded video clip teases, “The world’s largest migration isn’t what you think.” In the video, Dr. Erika Montague says that all the plankton in the world outweigh all other sea animals combined. Tiny jellyfish, shrimp, comb jellies, and other organisms lumped into the collective we call plankton are not just passive drifters; they have the ability to move vertically through the water column. You can see them flapping their fins or pumping their water bells like hard-working swimmers.

Oceanographers estimate that these tiny sea creatures might move as much water as the wind and the tides. “This happens all around the planet, in every ocean,” Montague says. “It’s amazing.” It is.

  

Darwinism's greatest adversary may be Darwinism?

Biologist Laments, “I Want Deeply for [Darwinism] to Make Sense”
David Klinghoffer | @d_klinghoffer

In his important new book, coming out on September 12 from HarperOne, State University of New York biologist J. Scott Turner tells the story about the Christmas pony. As a gift for a child who wants a pony, a poor family could afford only a pile of horse manure. Traipsing downstairs on Christmas morning to behold this well-intentioned mess, the child delightedly squealed and clapped.Her parents asked her why. She answered, “Because I know there’s a pony in there somewhere.”

In evaluating the coherence of Darwinian theory, Dr. Turner finds many of his fellow biologists in much the same mood. Squealing and clapping, they know there’s a coherent theory in there somewhere.

His book,  Purpose and Desire: What Makes Something “Alive” and Why Modern Darwinism Has Failed to Explain It,  underlines that Turner is not an “anti-Darwinist.” On the contrary, he explains that “I want deeply for it” – meaning the modern theory of Darwinian evolution – “to make sense.” The reasons for his disillusion, which he outlines in this fascinating contribution to the evolution debate, turn upon long-ignored problems with the theory, and counterevidence from the mysterious nature of life itself.It is still a couple of months too early for reviews of Purpose and Desire, but Kirkus welcomes it with a pre-publication starred review as an “ingenious mixture of science and philosophy that points out major defects in Darwinism and then delivers heterodox but provocative solutions…a highly thought-provoking book.”

Turner writes:

For the longest time, we’ve been able to fudge these problems, carried along on the faith that, to paraphrase the punch line of an old joke, there had to be a pony in there somewhere. But the dread possibility is beginning to rear its head; what if the pony isn’t there?

The problem for modern Darwinism is, I argue, that we lack a coherent theory of the core Darwinian concept of adaptation.

It all unravels from there, thanks to unexpected insights from Biology’s Second Law – homeostasis – and the great 19th-century French physiologist Claude Bernard, writing just six years after Darwin’s Origin of Species. After some delay, the crisis for the evolutionary biologist is at hand.

Without giving away any more punch lines, I recommend this: Pre-order Purpose and Desire now, because if you do so, for a limited time only, you’ll also get two free e-books to go along with it. The free e-books are Fire-Maker: How Humans Were Designed to Harness Fire and Transform Our Planet, by biologist Michael Denton, and Metamorphosis, which I edited as a companion to the Illustra Media documentary. Find the details here. (Note: When we first pointed out this offer, the web page wasn’t working correctly. It’s now fixed.)

Well. Turner’s book is a great read, and while he’s not a proponent of ID, he turns a fresh new page for the case for design in nature. Promise: We’ll have more to say about his argument in due time.

Interview with a titan.

The political center is dead and gerrymandering killed it?:Pros and cons.

More fossils mean more doubt?

In Resolving Darwin's Doubt, New Cambrian Animal Fossils Are No Help at All

Evolution News & Views July 2, 2015 11:53 AM 

 

More complexity in the earliest multicellular animals intensifies what Discovery Institute's Stephen Meyer calls "Darwin's Doubt."

Euarthropods
A paper in Current Biology comes closest to demonstrating "the deep homology between exoskeletal features in an evolutionary continuum of taxa with distinct types of body organization." Author Javier Ortega-Hernández takes on "the euarthropod head problem" by finding similarities between two specimens from the Burgess Shale (Middle Cambrian). His analysis, though, only compares positions of complex tissues, not how they originated. Amid various controversies, he focuses on a relatively simple structure, the anterior sclerite (a front plate of cuticle) within one phylum, the true arthropods.

Despite its ubiquitous nature, the significance of the anterior sclerite remains controversial, as there is little agreement on the correspondence of this structure among stem- and crown-group euarthropods. [Emphasis added.]

His attempt at finding phylogenetic relationships, given such a trifling structure in a narrow range of animals, is less than convincing. Worse, he ignores the weightier matters of the explosive origin of the complex body plans of these animals.
Collinsium
Science media are excited about a new "spiky monster worm" from China, named Collinsium ciliosum (pictured above; original paper is in PNAS). If this is supposedly an ancestor of modern velvet worms, as researchers at the University of Cambridge claim, it was already complex, with spikes, a mouth with teeth, antennae, and filter feeding appendages. Its 72 spikes in rows down its back are particularly noteworthy. If anything, it looks more complex than "Today's 180 or so species of velvet worms [that] all look and act pretty much the same" (Science Magazine). "This isn't the first time that an ancestral group has displayed more diversity than its modern-day relatives," Live Science comments. If this is evolution, it's going backwards.

The critter is one of the first known animals on Earth to develop protective armor and to sport specialized limbs that likely helped it catch food, the researchers said. This newfound species lived during the Cambrian explosion, a time of rapid evolutionary development, they said.

Abrupt appearance? Rapid development? How this helps the evolutionary story is not clear. The Cambridge news item offers word salad as a distraction from the issues raised in Meyer's book Darwin's Doubt, which they simply ignore.

"Animals during the Cambrian were incredibly diverse, with lots of interesting behaviours and modes of living," said Ortega-Hernández. "The Chinese Collins' Monster was one of these evolutionary 'experiments' -- one which ultimately failed as they have no living direct ancestors -- but it's amazing to see how specialised many animals were hundreds of millions of years ago. At its core, the study of the fossil record seeks answers about the evolution of life on Earth that can only be found in deep time. All the major biological events responsible for shaping the world we inhabit, such as the origin of life, the early diversification of animals, or the establishment of the modern biosphere, are intimately linked to the complex geological history of our planet."

Anomalocaris
Star of the Illustra documentary Darwin's Dilemma, the apex predator Anomalocaris was mentioned recently in connection with a new member of its family. This one, a giant named Aegirocassis benmoulae, was found in Morocco, indicating the global extent of the anomalocaridids. Unlike its more famous relative, "this anomalocaridid from the Ordovician exposes a second set of body flaps and reopens the question of how the two branches of arthropod legs evolved," Gregory Edgecombe notes in Current Biology. The authors of the paper in Nature are not much help to Darwin, having to invoke "convergent evolution" again:

Among arthropods, the size of A. benmoulae (over 2 m in length) is paralleled only by some pterygotid eurypterids and terrestrial arthropleurids. The evolution of gigantic filter-feeders within clades of nektic macrophagous predators is well documented in Mesozoic pachycormid fish and Cenozoic sharks and whales. The huge size of A. benmoulae represents a much earlier example of a filter-feeding lifestyle correlating to gigantism. The abundance of gigantic anomalocaridid filter-feeders in the high palaeolatitude Fezouata Biota points to a complex planktic ecosystem. Early Cambrian anomalocaridid filter-feeders also fed on zooplankton, but they remained relatively small. Although the Cambrian Explosion saw the establishment of the first complex planktic ecosystems, the convergent (Supplementary Text) rise of giant filter-feeding anomalocaridids during the Ordovician followed an increase in the abundance and diversity of phytoplankton and a consequent zooplankton radiation as part of the Great Ordovician Biodiversification Event.

Once again: abrupt appearance of complex body plans, complex ecosystems, and convergent evolution. None of this helps the evolutionary story or answers the key issue: where did the genetic information come from to build complex body plans with hierarchical structures and functional organs composed of new tissues and cell types?
Hallucigenia
When Hallucigenia was first found in the Burgess Shale a century ago, paleontologists couldn't tell top from bottom or front from back. The bizarre creature with paired spines pointing away from its paired legs was missing an important part: its head. Now, the head has been found. It's complex, with a pair of eyes and rows of teeth. This requires explaining more cell types and tissue types than before, exacerbating the problem Stephen Meyer identified in his book.
Martin R. Smith from Cambridge, with Jean-Bernard Caron from the Toronto Museum of Natural History, announced the discovery in Nature. Other sites, like PhysOrg and New Scientist, picked up the story and showcased the new artwork. For BBC News, Smith described his initial reaction:

By delicately chipping away at the rock, scientists found a spoon-shaped head with some surprising features.
"When we put it into the electron microscope, we were delighted to see not just a tiny pair of eyes looking back at us, but also beneath them a really cheeky semi-circular smile.
"It was as if the fossil was grinning at us at the secrets it had been hiding," explained Dr Smith.
Inside the creature's mouth, the researchers found a ring of teeth and then another set of teeth running from its throat down towards its stomach.

Most of the chatter is preoccupied with where to put this creature in a Darwinian phylogenetic tree. For a long time, animals were lumped together by their type of body cavity (coelom). That's changed; in 1997, Aguinaldo invented the category "ecdysozoa" ("molting animals") based on ribosomal RNA comparisons. This lumped together everything from butterflies to roundworms, from tardigrades ("water bears") to centipedes, from velvet worms to spiders. But is such a clade meaningful? "These disparate phyla are united by their means of molting, but otherwise share few morphological characters -- none of which has a meaningful fossilization potential." Smith and Caron note. "As such, the early evolutionary history of the group as a whole is largely uncharted."
The purpose of the grouping was to try to unite all the creatures that supposedly had a common ancestor. A more meaningful designation would account for the complexity and unique features of each animal, without forcing it into preconceived notions of common ancestry. Hallucigenia is a prime example. This creature had eyes, a mouth, teeth, a throat, a foregut, a stomach, and an anus. It had appendages that could reach its mouth. It had seven pairs of spines, each emerging from "a buttress of soft tissue," arranged with curvatures from front to back, protecting the entire animal. It had claws on the ends of the legs.
It's not just the cell types that need to be explained, but their arrangement into functional structures. These structures, moreover, need to be integrated into a functional animal in its ecosystem. And, they need software in some central nervous system that allowed the animal to use all of it. This is hierarchical organization, none of which is seen in the Precambrian layers beneath.
Just-So Storytelling
Live Science has a nice gallery of these and other Cambrian critters. Interesting  animals, but nothing new here. More of the same complexity. More of the same just-so storytelling that assumes undirected evolution. More distraction from the main question: what is the source of complex specified information to build a complex animal? How could it emerge from a blind, unguided process?

 

Tactility v. Darwin.

Design at Your Fingertips: Researchers Struggle to Model Sense of Touch
Evolution News | @DiscoveryCSC

The late pianist Victor Borge (1909-2000) was beloved not only for his comedy shtick but also for the sensitivity of his keyboard touch. He maintained the ability to interpret the most subtle pieces such as Claire de Lune (click on the image above to go there) with extreme delicacy all the way to age 90, when he was still giving 60 performances a year. It would be hard to design a robot with that level of durability, reliability, or sensitivity. Scientists know, because they’re having a hard time understanding it, let alone imitating it.

Four researchers from the University of Chicago and the University of Sheffield (UK) have made major progress over previous attempts to model the sense of touch. In a paper in the Proceedings of the National Academy of Sciences, “Simulating tactile signals from the whole hand with millisecond precision,” they announce their new mathematical model of a single hand’s neural responses under a variety of fingertip-touch experiments, hoping to assist robotics engineers wishing to imitate human touch response. Note the words code and information:

When we grasp an object, thousands of tactile nerve fibers become activated and inform us about its physical properties (e.g., shape, size, and texture). Although the properties of individual fibers have been described, our understanding of how object information is encoded in populations of fibers remains primitive. To fill this gap, we have developed a simulation of tactile fibers that incorporates much of what is known about skin mechanics and tactile nerve fibers. We show that simulated fibers match biological ones across a wide range of conditions sampled from the literature. We then show how this simulation can reveal previously unknown ways in which populations of nerve fibers cooperate to convey sensory information and discuss the implications for bionic hands. [Emphasis added.]

Unlike previous experiments that attempted to measure neural spikes from individual sensors in the skin of monkeys or humans, this new model simulates the responses of thousands of sensors based on knowledge of their classifications and distributions in the skin of the human hand. The team incorporated three classes of nerve fibers into the model:

Slowly adapting (SA) sensors: these respond primarily to spatial information from the stimulus.

• Rapidly adapting (RA) sensors: twice as densely packed as SA sensors, these provide a mix of spatial and vibration responses.
• Pacinian sensors: less densely packed than the other types, these neurons are sensitive to vibrations and waves generated by movement across the skin.

Each of these fibers produces spike trains that encode different aspects of the stimulus, such as edges, compression, and vibration. One type alone might not convey much about the source, but together, they give the brain a rich array of data. Interpreted correctly, this information allows the brain to draw conclusions about size, shape, and texture of an object by touch alone. A blind person can thus “see” Braille letters with the fingertips where these neurons are most densely packed: “each fingertip contains just under 1,000 fibers,” the paper states, providing fine resolution, especially from the high-resolution SA1 fibers.

The spike trains become more complex as the fingertip is moved into or across the source, activating more of the RA and PC fibers. Simply pressing a key on a computer keyboard is a complex act, with surrounding neurons becoming involved as pressure is applied or released. Moving a finger across a surface sets up waves that propagate throughout the hand, activating more sensors along the length of the finger and into the palm. This all happens within milliseconds (thousandths of a second), as it must when you consider the fast action of typing or playing a rapid piano piece. Even though PC fibers are less densely populated, their activity “dwarfs that of active SA1 or RA fibers,” the authors say, since they almost all become activated during a grasping operation or when feeling vibrations.

The authors describe their efforts to “tune” or “fit” their model to known facts about neurons in the hand. Eventually, they achieved a good match for things like edge detection, edge orientation, and direction of motion for simple actions. Nevertheless, they omitted important capabilities such as temperature or pain — two important inputs that can generate reflex actions that activate arm muscles to jerk the hand away before the brain is aware of danger. Needless to say, their model completely overlooks things like sweat glands, blood vessels, immune cells, and all the other equipment packed into a fingertip.

While the new model reflects admirable progress in understanding the sense of touch, and while it will undoubtedly help engineers seeking to improve prosthetic devices and robotic capabilities, the authors admit in the last section a number of limitations to their model. For instance, they tuned their model to information from rhesus macaques, knowing that humans have an additional type of tactile sensor called the SA2 fiber. They also fit their model to compression actions but not to sliding actions. In addition, they didn’t take fingerprints into account. Here’s why that could be a serious shortcoming of the model:

Third, the skin mechanics model treats the skin as a flat surface, when in reality, it is not. The 3D shape of the skin matters during large deformations of the fingertip. For example, pressing the fingerpad on a flat surface causes the skin on the side of the fingertip to bulge out, which in turn, causes receptors located there to respond. Such complicated mechanical effects can be replicated using finite element mechanical models but not using the continuum mechanics (CM) model adopted here. To the extent that friction is a critical feature of a stimulus — for example, when sliding a finger across a smooth, sticky surface — or that the finger geometry plays a critical role in the interaction between skin and stimulus — as in the example of high-force loading described above — the accuracy is compromised. Under most circumstances, the model will capture the essential elements of the nerves’ response.

Another limitation may be even more significant. They didn’t take into account the networking of responses in adjacent nerves. Their model treats an affected area as an isotropic “hotspot” wherein all the fibers react the same way, but nerve fibers are known to branch out and affect neighboring fibers. This can produce complex interactions between neurons, adding to the encoded tactile information the brain receives.

Let’s dive one level deeper into the details to consider what goes on at the cellular level. A neuron embedded in the skin does not see anything. It “feels” the outer skin deforming slightly because it contains mechanosensitive portals in its membranes. These portals let some ions in, and others out, creating a wave train of signals down the cell’s length. That’s the electrical “spike” the authors talk about, but it doesn’t just happen without each neural cell first being equipped with molecular machines able to respond to pressure, and able to quickly reset and re-fire as the source changes. As the signals propagate toward the brain, the neurons must cross synapses that convert the electrical signals to chemical signals and back again, preserving the information and the timing of the signals as we saw in the case of 3-D hearing.

Once again, the simplest, ordinary action of touching a fingertip on a surface is vastly more complex than we could conceive, challenging scientists to come up with simplified models to understand it. With this in mind, try an experiment: with your eyes closed, touch your index finger to a variety of surfaces around you: a table top, clothing, bread, liquid, the skin of your arm, a puff of air from your lips. Try to discern by touch alone information about each object’s friction, temperature, smoothness, shape, and hardness. Think of all those thousands of sensors providing that information to the brain with millisecond precision! Imagine what the brain has to deal with you when you plunge your whole body into a cold pool on a hot summer day.

The authors say nothing about evolution in their paper. Design is so abundantly obvious in the human body, as Steve Laufmann discussed in his recent ID the Future podcasts about Howard Glicksman’s series on physiology, our best engineers cannot even conceive of approximating that level of functional coherence, performance and integration. Not even close.