October 25, 2020 | David F. Coppedge

How to Do Biology Without Darwin

A paper and press release compare fish and humans, but avoid falling into the Darwin just-so-story habit.

Just-so stories about evolution are so common in science media, they seem second nature. What’s more newsworthy these days is when a biology announcement does not mention evolution.

Stuff Chuck back in the box when he doesn’t belong.

Biologists often assert their axiom that nothing in biology makes sense except in the light of evolution. Darwin’s theory, however, is often irrelevant to the actual facts at hand. For instance, pharmacologists commonly test new drugs or vaccines on mice. In such research, is it necessary to state the belief that humans evolved from mice, or share a common ancestor? Evolutionists may believe that, and extend their assertion that the drug works because humans evolved from mice, but that is a circular argument. They overlook the possibility that humans and mice share common designs. The evidence can be fit to either belief.

A press release from Northwestern University came close to the storytelling trap, but avoided it. The title suggested evolution: “Findings shed light on the ancient origins of speed control during movement.” Actually, that wording fits the creation model, too; it doesn’t say that the “ancient origins” involved common ancestry millions of years ago, as opposed to common design more recently. That’s as close to Darwinism as the press release got.

Science writer Megan Fellman focused on the facts: “Learning how a zebrafish moves will aid understanding of human movement and disorders.” That’s fine, because humans and fish have spinal cords, muscle cells and neurons that share many similarities at the cellular level. A nerve in a fish works like a nerve in a human being.

Movement in animals is complex, especially in human beings. A variety of neurons coordinate the activity and inactivity of our muscles, and without that coordination we’d fall flat on our face when we went for a walk.

Scientists have known for quite some time how motor neurons in the spinal cord that activate muscles are organized to generate more forceful output, to transition from walking to jogging to running, for example. Little is known, however, about how spinal inhibitory interneurons work to inhibit, or silence, other neurons and related muscle groups in coordination with the active muscle groups across changing speeds.

So far so good. Just the facts.

Now a Northwestern University research team has discovered in a study of zebrafish that there is a very orderly relationship between when these critical inhibitory neurons are born, their participation in different speeds of movement and what part of a motor neuron they innervate. As a result of this compartmental setup, the amounts of inhibition received by the motor neurons are tuned to different speeds of movement.

Zebrafish is a model organism whose spinal cord works in a fashion similar to our own. Leaning more about the undulating movement of the swimming fish will allow scientists to better understand how humans walk.

That assertion will need to be demonstrated (since fish don’t walk), but it does not necessarily imply common ancestry by natural selection over millions of years. The statements are consistent with intelligent design.

“It’s a bit like discovering parts for a combustion engine during an archaeological dig.”

The article teeters on the edge of Darwinism with the word “primitive” in the following quote, but never quite falls into Darwin’s warm little philosophical pond. Actually, a fish can be described as primitive compared to a human without assuming common ancestry, and embryos can be described as primitive compared to adults without assuming Darwinism. In the last sentence, a wonderful design analogy pops in by surprise:

“A better understanding of how circuits in the spinal cord are organized to coordinate movements puts us in a better position to repair things when damaged or diseased,” said David McLean, corresponding author of the study.

“The fact that we see this pattern in the spinal cord, a relatively primitive part of the nervous system, and in fish, a relatively primitive vertebrate, means that nervous systems made use of this compartmental scheme to regulate activity much earlier than we would have expected,” he said. “It’s a bit like discovering parts for a combustion engine during an archaeological dig.”

Core elements of a car chassis and engine (Illustra Media)

Dr McLean shows an appropriate focus in his work. He’s looking to understand patterns (designs) in complex systems.

“As neuroscientists, our job is to make sense of the enormous complexity we find in the nervous system that generates behavior,” McLean said. “One way we do that is to look for patterns that give us a sense that there is an underlying logic — an algorithm that bridges species and is useful in other parts of the brain. This, I think, is one such pattern.”

His colleague also shows a similar focus on design in this quote:

“This compartmental pattern exists in other animals and brain regions, but using zebrafish we discovered clear functional consequences by watching the circuits develop, similar to understanding how a car works by following the assembly line,” said Sandeep Kishore, first author of the study and a research associate in McLean’s lab.

That’s how to do biology without evolution. Stick to the facts. Let the philosophers and theologians argue about origins.

Incidentally, the paper in Science Magazine by Kishore, McLean and two other colleagues, “Orderly compartmental mapping of premotor inhibition in the developing zebrafish spinal cord,” makes no mention of evolution except to say in passing that “the genetic origins of spinal neurons are evolutionarily conserved” (i.e., unevolved).

Cars exhibit similarities but are all intelligently designed.

Thank you Ms Fellman and Drs McLean and Kishore for keeping your statements free of Darwinism. Much of our time at CEH is spent extracting the meat of science from the garbage of assumptions about evolution and millions of years. It may well be that you believe in Darwinian evolution; it is probably the case there at a secular university where evolutionists in academia tend to rule with totalitarian mind control. You have demonstrated, though, that it is neither necessary nor helpful to insert Darwin where he doesn’t belong.

We especially liked the references to intelligently-designed objects like combustion engines and cars. Keep up the good work, and best wishes figuring out circuit-controlled movement. This short film might provide inspiration.


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