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Tuesday 13 September 2022

Darwin's design Inference?

 Charles Darwin’s Freudian Slip 

Robert F. Shedinger 

Last April, I wrote a post for Evolution News about the reception of Darwin’s book dealing with fertilization methods in orchids. Darwin, rather than following up the Origin of Species with the publication of his big book on species, which was three-quarters complete, instead turned to botanical concerns and published his orchid monograph in 1862. Darwin confessed to Asa Gray that his orchid book would serve as a “flank movement on the enemy.” 


Darwin clearly hoped that readers of the orchid book would be so overwhelmed with the variety of contrivances (his word) found in orchids to assure fertilization by insects that they would marvel at the power of natural selection to produce them. I argued previously that the orchid book was Darwin’s stealth attempt to provide the evidence of natural selection missing from the Origin, which was a mere abstract of his theory, and missing from the big book, which he never published.


A Grand Intelligent Designer

Darwin’s strategy, however, failed miserably. When reviews of the orchid book appeared in the British press, reviewers almost unanimously hailed it as one of the great books of natural theology. The amazing variety of contrivances by which orchids assure their fertilization by insects testified, in the opinion of these reviewers, to the existence of a grand intelligent designer. 


M. J. Berkeley, for example, in the London Review, opined:

Most certainly, so far from justifying anyone in considering the author as heretofore as a heathen man or an heretic for the annunciation of his theory, the whole series of the Bridgewater Treatises will not afford so striking a set of arguments in favour of natural theology as those which he has displayed. 

The Bridgewater Treatises, of course, were a series of writings commissioned by Francis Henry Egerton, the eighth Earl of Bridgewater, designed to demonstrate the power, wisdom, and goodness of God as manifested in creation. One would think that Darwin would be livid at someone comparing his orchid book to the Bridgewater Treatises. I thought so myself until I did additional research. 

A Surprising Discovery 

I recently discovered a letter by Darwin that I had originally overlooked. When writing up his orchid research, Darwin initially planned to publish it as a paper in the Linnean. But it became too long for a journal article, so he decided to publish it as a book instead. In September 1861, Darwin contacted his publisher, John Murray, to gauge Murray’s interest in potentially publishing this technical monograph on orchids. Darwin wrote: 

Will you have the kindness to give me your opinion, which I shall implicitly follow. — I have just finished a very long paper for Linnean Society and yesterday for the first time it occurred to me that possibly it might be worth publishing separately, which would save me trouble and delay. — The facts are new & have been collected during 20 years & strike me as curious. Like a Bridgewater Treatise the chief object is to show the perfection of the many contrivances in Orchids. 

Darwin could hardly complain about others comparing his orchid book to the Bridgewater Treatises when he himself had done the very same thing (though not publicly)! 


When one considers Darwin’s use of the word “contrivances” in his orchid book, the very word William Paley had used throughout his Natural Theology, and his own comparing of his orchid book to a Bridgewater Treatise in his letter to Murray, it looks like Darwin was as impressed as everyone else by the amazing ingenuity in orchids and could not ignore the evidence for design. 


If Sigmund Freud were alive today, he might well say that Darwin slipped!


File under "Well said" LXXX.

Those whom God wishes to destroy, he first makes mad.



Euripides 


Ps.ecclesiastes7:13NIV"Consider what God has done: Who can straighten what he has made crooked?"

The journey from is to ought without a bridge?

 Atheists Who Scold Us on Morality Unwittingly Acknowledge God’s Existence 

Michael Egnor 

Biologist P. Z. Myers detests challenges to his atheism based on the reality of Objective Moral Law:

There is a common line of attack Christians use in debates with atheists, and I genuinely detest it. It’s to ask the question, “where do your morals come from?” I detest it because it is not a sincere question at all — they don’t care about your answer, they’re just trying to get you to say that you do not accept the authority of a deity, so that they can then declare that you are an evil person because you do not derive your morals from the same source they do, and therefore you are amoral. It is, of course, false to declare that someone with a different morality than yours is amoral, but that doesn’t stop those sleazebags. 

Actually, Christians don’t ask, “Where do your morals come from?” in order to call atheists evil. We do it to point out that objective morality is powerful evidence for God’s existence. 

Subjective and Objective 

How so? From our human perspective, moral law can have two origins — subjective and objective.


Subjective moral law is based on human opinion. It may just be one man’s opinion, or it may be the collective opinion of a group of people. If our standards are wholly subjective, dislike of strawberry ice cream and dislike of genocide are not qualitatively different. The dislike is just human opinion.


Objective moral law, by contrast, is outside of human opinion. It is something that we humans discover. We do not create it. Thus, objective moral law exists beyond mere human opinion.


Now a distinction emerges. Personal preferences (e.g., about ice cream) are qualitatively different from personal opinions about genocide — we oppose genocide because it is objectively wrong, not just because it is not quite to our taste.


Of course, if a value judgement prevails over other human value judgements, there must be Someone whose opinion is Objective Moral Law. There must be a Law-Giver.


Please note that this argument is ontological, not epistemological. It is not an argument about how well we can know what the Moral Law is. It is an argument that Objective Moral Law exists, regardless of how well we can or do know it.



Change my mind.

AntiJW  bigots: You're in a cult!

Me: aren't we all?

Ps. Are all cults created equal?

The thumb print of JEHOVAH :hummingbird edition.

 A Closer Look at Hummingbird Tongue Design 

David Coppedge 

One of the memorable moments in Illustra Media’s documentary Flight: The Genius of Birds is the hummingbird tongue animation (see it below). The unique nectar-trapping mechanism of unfurling flaps (lamellae) on supporting rods that automatically fold over to seal in the nectar was discovered by two biologists at the University of Connecticut (see the paper in PNAS). This was cutting-edge science, because most biologists previously had assumed the tongue worked by simple capillary action. 

The two biologists have continued their work since then, filming hummingbirds in the wild. Along with a mechanical engineer who is an expert in fluid mechanics, they published a paper in the Proceedings of the Royal Society B that should increase our admiration for the design of this structure. It’s not only a nectar trap; the hummingbird tongue is a micropump!


News from UConn Today includes a video clip (below) of the tongue in action. The new findings debunk the notion that capillary action called “wicking” draws nectar up the tongue. 

Rico-Guevara explains that a hummingbird’s tongue, which can be stuck out about the same length as its beak, is tipped with two long skinny tubes, or grooves. Rather than wicking, he says, the nectar is drawn into the tongue by the elastic expansion of the grooves after they are squeezed flat by the beak.


The tongue structure is collapsed during the time it crosses the space between the bill tip and the nectar pool, but once the tip contacts the nectar surface, the supply of fluid allows the collapsed groove to gradually recover to a relaxed cylindrical shape as the nectar fills it.


When the hummingbird squeezes nectar off its tongue during protrusion, it is collapsing the grooves and loading elastic energy into the groove walls. That energy subsequently facilitates the pumping of more nectar. 

In Concert with the Lamellae 

This pumping action apparently works in concert with the lamellae (flaps) shown in the Illustra film. The cylinders are in a flattened shape when they enter the nectar. Having been compressed by the beak, they store elastic energy that makes them rapidly expand in the fluid as they unfurl. This expansion helps to pump the fluid into the cylindrical cavity upward from the lamellae. That way, more nectar can be delivered into the bird’s mouth.


Figure 1 shows the beak in cross-section from a CT scan. It looks beautifully designed to squeeze the tongue’s cylinders during protrusion, with the lower bill fitting into spaces in the upper bill that spread laterally to flatten the tongue as it exits the bill tip. This design probably also squeezes the previous load of nectar into the mouth at the same time. “After complete loading, the grooves filled with nectar were brought back inside the bill and squeezed for the next cycle, all in less than a tenth of a second,” they observe. The caption for Figure 1 explains how these two mechanisms (pumping and trapping) work together: 

The hummingbird tongue fills with nectar even when only the tip is immersed. (a) Hummingbirds can drink from flowers with corollas longer than their bills by extending their bifurcated, longitudinally grooved tongues to reach the nectar. During protrusion, the tongue is compressed as it passes through the bill tip, which results in a collapsed configuration of the grooves (cross-section). (b) Upon reaching the nectar, the tongue tips fringed with lamellae roll open and spread apart, but some of the grooved portions of the tongue will never contact the nectar pool. For the grooves to fill with nectar, they must return to their uncompressed, cylindrical configuration. 

Why doesn’t the collapsed tongue rebound immediately after it leaves the beak and enters the air? That would result in open tubes that would need to fill by capillary action when they enter the nectar. But capillary action is much slower than the observed filling. Apparently the tongue material is designed to expand upon contact with the nectar. “After contacting the surface, the grooves expanded and filled completely with nectar,” they found. 

Birds in the Wild 

All hummingbirds have this mechanism. They filmed 32 wild birds, representing 18 species (in 7 of the 9 main hummingbird clades), with a high-speed camera in natural wild habitats, undergoing hundreds of feeding cycles — all with the same results. This allowed them to falsify the “century-old paradigm” of the capillary hypothesis and shed new light on this rapid, dynamic process. 

All observed licks followed the same pattern: tongue thickness was stable during protrusion of the tongue, and rapidly increased after the tongue tips contacted the nectar… After complete loading, the grooves filled with nectar were brought back inside the bill and squeezed for the next cycle, all in less than a tenth of a second. 

Capillary action could not have filled the cylinders this rapidly. In addition, no meniscus (diagnostic of capillarity) was observed to form in any of the 96 video sessions. The pumping action, by contrast, fills the entire tongue in just 14 milliseconds. Here’s how it works, according to their new model: 

We suggest that while squeezing nectar off the tongue during protrusion, the bird is collapsing the grooves and loading elastic energy into the groove walls that will be subsequently used to pump nectar into the grooves. The collapsed configuration is conserved during the trip of the tongue across the space between the bill tip to the nectar pool. Once the tongue tips contact the nectar surface, the supply of fluid allows the collapsed groove to gradually recover to a relaxed cylindrical shape until the nectar has filled it completely; hereafter, we refer to this previously undocumented mechanism as ‘expansive filling’. 

Flattened and Sealed 

The tongue stays flattened and sealed, in short, until it hits the nectar pool. Then, inside the fluid, the tongue’s twin cylinders rapidly expand, pumping nectar up into the tongue as it darts into the flower at speeds of a meter per second. As the tongue is withdrawn, the lamellae then seal the cylinder tightly shut for delivery into the bird’s mouth. This is a wonderful dual mechanism that results in much more efficient food capture in far less time. 

Fluid trapping is the predominant process by which hummingbirds achieve nectar collection at small bill tip-to-nectar distances, wherein tongue grooves are wholly immersed in nectar, or when the nectar is found in very thin layers. Expansive filling accounts for nectar uptake by the portions of a hummingbird’s tongue that remain outside the nectar pool. The relative contributions of the two synergistic mechanisms(fluid trapping and expansive filling) to the rate and volume of nectar ultimately ingested are determined by the distance from the bill tip to the nectar surface during the licking process. 

In other words, these two “synergistic mechanisms” give the hummingbird the biggest possible nectar bang for the buck, regardless of how deep the nectar pool is. The new model explains how the tongue can fill up even in a short flower. Since hummingbirds already “have remarkably high metabolic rates, amazing speed and superb aeronautic control,” it is essential they get the optimum return on investment of feeding energy.  

All these traits result from the ability of hummingbirds to feed on nectar efficiently enough to fuel an extreme lifestyle out of a sparse, but energetically dense, resource. Therefore, the way in which they feed on nectar determines the peaks and span of their performance, and thus their behaviour (and evolutionary trajectory), across a range of environmental axes. 

How Did Evolution Contribute? 

But did evolutionary theory contribute anything to this study? The authors speculate briefly about “co-evolution” of flowers and their pollinators, but do not offer any “trajectory” by which a bird could evolve either of these mechanisms from ancestors lacking them. How useful is it to offer up evidence-free promissory notes like this? 

The new explanation of the mechanics of nectar uptake we provide here suggests that physical constraints are the main determinants of the relationship between pollinator type and nectar concentration, and can guide us through alternative hypotheses of hummingbird-flower coevolution. 

By contrast, they save their best lines for what might be termed (though not by the authors) intelligent design. The paper begins: 

Pumping is a vital natural process, imitated by humans for thousands of years. We demonstrate that a hitherto undocumented mechanism of fluid transport pumps nectar onto the hummingbird tongue. 

This implies a seamless connection between human design and biological design. They conclude on the design theme: 

Our discovery of this elastic tongue micropump could inspire applications, and the study of flow, in elastic-walled (flexible) tubes in both biological and artificial systems. 

You see, not only does a design focus inspire study of biological systems, it leads to better designed applications. Everyone can agree on this: hummingbirds are inspiring!