June 22, 2020 | David F. Coppedge

Our Senses Did Not Evolve

Despite what evolutionists say, our bodies with their amazing senses are the work of a designing intelligence par excellence.

How do our eyes move in perfect synchrony? (Live Science). Most of this article talks about an ability we take for granted: the ability to focus our two eyes on the same object.

“You have a spare one in case you have an accident, and the second reason is depth perception, which we evolved to help us hunt,” said Dr. David Guyton, professor of ophthalmology at The Johns Hopkins University.. But having two eyes would lead to double vision if they didn’t move together in perfect synchrony. So how does the body ensure our eyes always work together?

Benjamin Plackett started with that B.A.D. evolutionary statement, then immediately jumped to irreducible complexity.

To prevent double vision, the brain exploits a feedback system, which it uses to finely tune the lengths of the muscles controlling the eyes. This produces phenomenally precise eye movements, Guyton said.

Each eye has six muscles regulating its movement in different directions, and each one of those muscles must be triggered simultaneously in both eyes for them to move in unison, according to a 2005 review in the Canadian Medical Association Journal. “It’s actually quite amazing when you think about it,” Guyton told Live Science. “The brain has a neurological system that is fantastically organized because the brain learns over time how much stimulation to send to each of the 12 muscles for every desired direction of gaze.” 

Did the just-so story about our eyes evolving to help us hunt add anything to this article other than a laugh line?

Direct discrimination of structured light by humans (PNAS). Scientists at the University of Waterloo in Ontario, Canada found something new: humans can differentiate between light sensations they never experienced before. If eyes had ‘evolved to help us hunt,’ why would natural selection spend time giving the eye powers it would never use in real-life situations? Human eyes appear over-designed for situations more nuanced than for mere survival. This paper doesn’t mention anything about evolution.

Recent technological advances have enabled the creation of custom light fields with remarkable properties. Here we report an experiment that merges human visual perception with structured wavefronts and optical states that are nonseparable in polarization and spatial modes of light. We demonstrate that humans are able to discriminate between two polarization-coupled orbital angular momentum states with a high probability when directly viewing a structured light beam. The work brings the techniques of structured light to visual science applications and paves the way for methods of characterizing the structure of the macula and conducting experiments with human detectors and optical states with nonseparable modes.

Fantastic muscle proteins and where to find them (Max Delbrück Center for Molecular Medicine). Physiologists are still learning about how muscles work at the molecular level. This article says nothing about evolution, demonstrating that Darwinese is useless for understanding things. Leaving Charlie behind, let us look at some of the wonders inside muscle fibers:

Sarcomeres are tiny molecular machines, packed with proteins that tightly interact. Until now it has been impossible to separate proteins specific to the different subregions, especially in live, functioning muscle. “Titin-BioID probes specific regions of the sarcomere structure in vivo,” says Dr. Philipp Mertins, who heads MDC’s Proteomics Lab. “This has not been possible before.”

The team is the first to use BioID in live animals under physiological conditions and identified 450 proteins associated with the sarcomere, of which about half were already known. They found striking differences between heart and skeletal muscle, and adult versus neonatal mice, which relate to sarcomere structure, signaling and metabolism. These differences reflect the need of adult tissue to optimize performance and energy production versus growth and remodeling in neonatal tissue.

Individual sarcomeres are organized into muscle fibers.

Study shows nervous and immune systems ‘need to talk’ for bone repair (Medical Xpress). The communication of information is a hallmark of intelligent activity. It can be either programmed or live, as in two minds discussing conceptual ideas in language. Nerves, which communicate data to the brain for all the senses, have their own programmed language.

“Previous research has shown that immune cells are clearly important in bone repair, but what we determined in our study is that macrophages and their inflammatory signals also kickstart nerve regrowth in injured bone,” says Aaron James, M.D., Ph.D., associate professor of pathology at the Johns Hopkins University School of Medicine and co-senior author of both studies.

In other words, James explains, the team’s experiments revealed “that NGF-TrkA signaling is how macrophages ‘talk’ to nerve fibers so that bone healing can begin.”

This is a good example of scientific research aimed at understanding observable, repeatable natural phenomena, with the ultimate aim of helping people.

“We now understand that nerve growth and bone repair are linked processes,” James says. “Knowing this, we may be able to find ways to maximize our innate healing capacities. Developing new methods to improve bone healing would greatly benefit many people, especially the elderly, where injuries such as hip fractures often lead to worse outcomes than heart attacks.”

Scientists Decode How the Brain Senses Smell (New York University). Neuroscientists at the NYU Langone’s Department of Neuroscience and Physiology knew that humans have 350 different kinds of olfactory receptors, but the signaling system behind the sense of smell is far more dynamic than matching odorants to their receptors. Each signal arrives at a processing hub called a glomerulus (a ‘ball of string’ as named by early scientists, but actually a complex computer). When they measured the timing of responses to various odors in mice, the timing of the glomeruli activations worked together ‘like the notes in a melody,’ the researchers said. Surprisingly, smell is one of the most complicated of the senses. That’s because there are so many different odorants in the world, and their signals have to be sorted and organized before they reach the brain. We have a code in our nose!

“Our results identify for the first time a code for how the brain converts sensory information into perception of something, in this case an odor,” adds Dr. Rinberg. “This puts us closer to answering the longstanding question in our field of how the brain extracts sensory information to evoke behavior.

Update 6/22/2020: We smell in stereo! A new research paper in PNAS says that we can sense the direction of an odor, even if we can’t tell which nostril smells it more strongly.

Amazing FactsThe human brain exploits subtle differences between the inputs to the paired eyes and ears to construct three-dimensional experiences and navigate the environment. Whether and how it does so for olfaction is unclear, although humans also have two separate nasal passages that simultaneously sample from nonoverlapping regions in space. Here, we demonstrate that a moderate internostril difference in odor intensity consistently biases recipients’ perceived direction of self-motion toward the higher-concentration side, despite that they cannot report which nostril smells a stronger odor. The findings indicate that humans have a stereo sense of smell that subconsciously guides navigation.

The authors of the paper were doing well until the last sentence, when they said, “Exactly how the computation and utilization of olfactory stereo information are implemented in the brain awaits future experimentation to clarify, which will also help test the olfactory spatial hypothesis that olfaction evolved for the primary purpose of navigating in a chemical world.”

Diagram of the human ear, with cochlea at right.

Distinct roles of stereociliary links in the nonlinear sound processing and noise resistance of cochlear outer hair cells (PNAS). This Darwin-free research paper describes wonders in the inner ear, and how failure of particular links between hair cells can lead to deafness. The fine-tuning of these molecular links, when working properly, leads to all the richness of hearing. The ability to see how the hair cells work at the nanoscale (billionths of a meter) is opening up new vistas on the complexity of sound processing.

Our hearing organ, the cochlea, acts as an active sound amplifier rather than a simple detector due to the action of outer hair cells (OHCs). This active sound processing by OHCs requires specific hair bundle architecture in which stereocilia are connected to each other and to the overlying tectorial membrane by nanoscale extracellular links. But it remains unclear how these stereociliary links contribute to OHC function…. [W]e dissected the role of each link in OHC function. While the links connecting stereocilia and the tectorial membrane are essential for normal OHC function, the links connecting adjacent stereocilia together are more important for preventing hearing loss due to noise stress.

Cochlea, with cross-section of coil, and magnification of tectorial membrane with hair cells.

On a related subject, a preprint on bioRxiv discusses a particular myosin motor in the inner ear that, when mutated, causes deafness. The authors begin by expressing awe: “Cochlear hair cells possess an exquisite bundle of actin-based stereocilia that detect sound.” The particular myosin motor they studied, MYO15, acts as a strain sensor; it “traffics and delivers critical molecules required for stereocilia development and is essential for building the mechanosensory hair bundle.”

Music therapy: It’s all in the beat (Medical Xpress). Music is one of those human distinctives that goes far beyond physical needs for survival. This research project shows there’s tremendous variety in people’s taste for music. And even when cognizance starts to diminish in the aged, music can still have a therapeutic effect.

Decades after the “Mozart effect” gripped the world, music has established a solid footing in medical research thanks to music therapy….

“When people go into an aged care home, they just sit all day. They don’t know what to do. But when you bring music in, they come alive. You see what they were like or who they are as a person because they recognize the music when they don’t recognize other things,” says Felicity. “People remember things from their past when it’s paired with music. It brings back memories and those memories are often good memories. We usually associate music with good memories. And that calms them down and helps them remember who they are.”

What a beautiful thing, to have non-verbal communication via music that makes a person’s face light up and gives them moments of pure joy. The joy may be inexpressible to those losing memory and cognitive function, but it makes them feel alive at a deeper, richer level.

Think of the joy we would have in a Darwin-free world. Wouldn’t it be grand without the silly just-so stories and blank statements about how things evolved? Let science return to its long-standing aim of understanding nature to help us live better. Studying the intricate details of olfactory coding, or human vision, or hearing, or muscles for our kinesthetic sense – this is a worthy endeavor, and it enriches our lives. We should stand in awe and wonder—with gratitude—for the bodies we have been given to use for good.

Take your Chuck and stuff it.

Many will see the hand of God in these designs, but these articles illustrate that scientists do not need to identify the designing intelligence to understand how things work and to marvel at their intricacies.

Science will proceed just fine without Chuck-in-the-Box popping in uninvited. Help science get over its intoxication with Darwine and return to a sober yet joyful investigation of our fantastic endowments.

 

 

 

 

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