Psychologists don’t really believe that, do they?

They really need to get out more, dissect a frog brain or something, if they’re still clinging to that triune brain nonsense. According to Salon, some psychologists still think that’s valid. The author summarizes an article that…

…addresses (and debunks) one of the most commonly-used metaphors in evolutionary psychology, the idea that the human brain evolved from lower life forms and hence has evolutionary remnants from those animals — akin to an onion with layers.

If you’ve ever heard someone speak of you possessing a “lizard brain” or “fish brain” that operates on some subconscious, primal level, you’ve heard this metaphor in action. This is called the triune-brain theory; as the authors write, the basic crux of it is that “as new vertebrate species arose, evolutionarily newer complex brain structures were laid on top of evolutionarily older simpler structures; that is, that an older core dealing with emotions and instinctive behaviors (the ‘reptilian brain’ consisting of the basal ganglia and limbic system) lies within a newer brain capable of language, action planning, and so on.”

Whoa. That’s silly. Of course, I have an edge: my early career in graduate school was spent studying the neuroanatomy and physiology of fish, and yes, they have a hindbrain, midbrain, and forebrain — all the pieces are there, they develop to different degrees in different lineages, and there aren’t linear ‘steps’ in evolution where, all of a sudden, there are jumps to whole new brain architectures appearing. Even before that, as an undergraduate taking neuroscience from Johnny Palka, I recall how insistent he was that we had to regard the brain of Drosophila as both existing and capable of sophisticated processing. (It’s true, some people think insects don’t have brains. They’re wrong.)

I wonder if this is another consequence of the belief in Haeckel’s erroneous ideas. I’ve skimmed through Dr Spock’s Baby Book, and was surprised to see how much rekapitulationstheorie saturates that book. The creationists love to claim that introductory biology texts teach it as fact, when my experience is that they explain how it’s wrong; they should look into the child psychology texts if they want better examples of a bad idea being promoted today.

So I had to look into the paper described in the Salon article. It’s titled “Your Brain Is Not an Onion With a Tiny Reptile Inside”, which is excellent. It gets right down to addressing the misconception from the very first words. The abstract is also succinct and clear.

A widespread misconception in much of psychology is that (a) as vertebrate animals evolved, “newer” brain structures were added over existing “older” brain structures, and (b) these newer, more complex structures endowed animals with newer and more complex psychological functions, behavioral flexibility, and language. This belief, although widely shared in introductory psychology textbooks, has long been discredited among neurobiologists and stands in contrast to the clear and unanimous agreement on these issues among those studying nervous-system evolution. We bring psychologists up to date on this issue by describing the more accurate model of neural evolution, and we provide examples of how this inaccurate view may have impeded progress in psychology. We urge psychologists to abandon this mistaken view of human brains.

Then Cesario, Johnson, and Eisthen name names. They show that this misbegotten misconception is a real issue by going through the literature and introductory textbooks.

Within psychology, a broad understanding of the mind contrasts emotional, animalistic drives located in older anatomical structures with rational, more complex psychological processes located in newer anatomical structures. The most widely used introductory textbook in psychology states that

in primitive animals, such as sharks, a not-so-complex brain primarily regulates basic survival functions. . . . In lower mammals, such as rodents, a more complex brain enables emotion and greater memory. . . . In advanced mammals, such as humans, a brain that processes more information enables increased foresight as well. . . . The brain’s increasing complexity arises from new brain systems built on top of the old, much as the Earth’s landscape covers the old with the new. Digging down, one discovers the fossil remnants of the past. (Myers & Dewall, 2018, p. 68) [no relation –pzm]

To investigate the scope of the problem, we sampled 20 introductory psychology textbooks published between 2009 and 2017. Of the 14 that mention brain evolution, 86% contained at least one inaccuracy along the lines described above. Said differently, only 2 of the field’s current introductory textbooks describe brain evolution in a way that represents the consensus shared among comparative neurobiologists. (See https://osf.io/r6jw4/ for details.)

Not to blame only psychologists, they also point out that Carl Sagan popularized the idea further in The Dragons of Eden. I hate to puncture the warm happy glow Sagan’s name brings to many of us, me included, but that was a bad book. Don’t ask an astronomer to explain brain evolution and consciousness, ever. I’m looking at you, Neil.

The authors illustrate the misconception well. It’s a combination of errors: the idea that evolution is linear rather than branching, that humans are the pinnacle of a long process of perfecting the brain, and that we possess unique cerebral substrates to produce human capabilities. It isn’t, we aren’t, we don’t.

Incorrect views (a, b) and correct views (c, d) of human evolution. Incorrect views are based on the belief that earlier species lacked outer, more recent brain structures. Just as species did not evolve linearly (a), neither did neural structures (b). Although psychologists understand that the view shown in (a) is incorrect, the corresponding neural view (b) is still widely endorsed. The evolutionary tree (c) illustrates the correct view that animals do not linearly increase in complexity but evolve from common ancestors. The corresponding view of brain evolution (d) illustrates that all vertebrates possess the same basic brain regions, here divided into the forebrain, midbrain, and hindbrain. Coloring is arbitrary but illustrates that the same brain regions evolve in form; large divisions have not been added over the course of vertebrate evolution.

I’m kind of disappointed that this obvious flawed thinking has to be pointed out, but I’m glad someone is explaining it clearly to psychologists. Can we get this garbage removed from the textbooks soon? Or at least relegated to a historical note in a sidebar, where the error is explained?

Water: scary stuff

It doesn’t look like much at the beginning, but this dam failure in Michigan led to thousands of people being evacuated, destruction of bridges and homes downstream, and some houses were flooded to a depth of 9 feet. All it took was a little rain. OK, a lot of rain.

Here’s an analysis of the failure. There was something more going on.

This video is going to be a classic in the teaching of geotechnical failures, but it also clarifies the events that led to the Edenville Dam failure. It would have been simple to ascribe this to a simple overtopping event that occurred when the capacity of the spillway was exceeded. But in reality the events are are more worrying than that – the dam appears to have undergone a slope failure; a failure of its integrity. This should never occur, and to me it suggests that the problems at the Edenville Dam went further than known issues with the spillway.

So not just rain, but also negligence by whoever had responsibility for the dam. It turns out that this dam was privately owned, by absentee landlords with a criminal history who neglected it, refused to do necessary repairs and expansion, and had their federal license to run the dam revoked for their greedy refusal to do what was needed. I guess it is unsurprising that Lee Mueller is a Randian Trumpkin who lives in Las Vegas.

America’s crumbling infrastructure isn’t helped by the parasites and rentiers who’ve taken it over.

Buttons and threads, or how to achieve criticality in a non-linear fashion

I learned something a long, long time ago, first in studying the origin of life, and then in studying the relationships within networks of genes, and now when thinking about basic epidemiology. Nothing is linear. It’s an idea that’s been discussed since at least the 1980s, when Stuart Kauffman applied it to the logic of the emergence of life on Earth. Here he is talking about the appearance of autocatalytic sets, that is, collections of interlinked enzymes (or ribozymes) that generate emergent properties, like a metabolism.

Now, the next question is how hard is it to get such systems? Does it take a careful crafting of a chemist, or can it arise by chance? The body of theory I’ve been working on now for more than a decade suggests that it’s not hard.

You see this with an analogy: suppose you take 10,000 buttons and spread them out on a hardwood floor. You have a large spool of red thread. Now, what you do is you pick up a random pair of buttons and you tie them together with a piece of red thread. Put them down and pick up another random pair of buttons and tie them together with a red thread, and you just keep doing this. Every now and then lift up a button and see how many buttons you’ve lifted with your first button. A connective cluster of buttons is called a cluster or a component. When you have 10,000 buttons and only a few threads that tie them together, most of the times you’d pick up a button you’ll pick up a single button.

As the ratio of threads to buttons increases, you’re going to start to get larger clusters, three or four buttons tied together; then larger and larger clusters. At some point, you will have a number of intermediate clusters, and when you add a few more threads, you’ll have linked up the intermediate-sized clusters into one giant cluster.

So that if you plot on an axis, the ratio of threads to buttons: 10,000 buttons and no threads; 10,000 buttons and 5,000 threads; and so on, you’ll get a curve that is flat, and then all of a sudden it shoots up when you get this giant cluster. This steep curve is in fact evidence of a phase transition.

If there were an infinite number of threads and an infinite number of buttons and one just tuned the ratios, this would be a step function; it would come up in a sudden jump. So it’s a phase transition like ice freezing.

Now, the image you should take away from this is if you connect enough buttons all of a sudden they all go connected. To think about the origin of life, we have to think about the same thing.

The pattern should also affect how we think about genes. We’ve got about 20,000 genes; each gene influences the expression of some set of other genes. You may think you know exactly which genes are directly affected by a gene you are interested in — you can do experiments and work out the connections, a process called epistasis — but because each of those genes also have multiple connections, you in effect have to consider that every single gene in some way influences the activity of every other gene. Tug on one, and every other gene in the system is affected. Each of us is a supercluster of interacting genes, being tugged on in various ways by the environment.

I’m not an epidemiologist, but this also how I think about the pandemic. I am a button. I’ve been alone for months; if I had gotten the disease, I would have suffered alone but I’d also have been a dead-end for the virus. Now my wife is home, another button, and we are tied together with a red thread such that if I get the disease, she almost certainly will, and vice versa. But also, she was living with my daughter, her husband, and my granddaughter for a few months, she was part of a four-button cluster, which I’ve now joined. If one of us had the virus, it would have readily spread within that group. But it would have ended there.

Unless…what if I cheated? I decided to go out to a bar and chat with ten friends. I’ve basically connected a red thread to each of their clusters, and increased my connectivity greatly. Maybe you think it’s still a manageable number, but that’s only because you don’t see all the red threads outside of your immediate group. The point of Kauffman’s analogy is that the expansion of the network is not linear, as you might naively expect, but jumps rapidly as the number of connections increases, and can undergo a phase transition, where just going out to a bar can achieve criticality, and suddenly you are connected to everyone in the country, and the virus has avenues to reach everyone.

So think of yourself as a button. Every time you touch someone, lean in close and breathe their air, you are tying a red thread to them, linking your fate to some degree to them. You can safely build a little network with close family, and you’re still OK — the threads tangle together just your small family unit. But if your child has a playdate with a neighbor’s kid…they have made a new thread that encompasses everyone in your family, and everyone in the neighbor’s family, and you’ll have no idea how many threads connect you all. And if you decide to take the whole family to that newly opened beach and mingle with thousands of other people, forget about it — the number of connections have shot up exponentially. You’ve lost all control.

The problem is that people don’t grasp the idea of exponential increases intuitively. I don’t. I’ve worked with enough models that I know that these kind of phenomena can produce surprisingly large effects rapidly, though, and that our current situation is a perfect example of that kind of phenomenon, and damn, stay home and stop stitching all those buttons together.

Back to the spider grind

I took a tour of my house this morning to see how the spiders were shaping up. I found lots, even more than I did last week. Some were familiar, like Attulus fasciger, who had captured a mosquito-like creature. Good work, young lady!

Of course there were lots of Salticus scenicus around.

The exciting but somewhat disappointing discovery was that Parasteatoda abounded — they’d colonized several inset corners of the house and areas around the downspouts, where they had good cover and great places to hide.

The disappointing part was my own failure: I couldn’t get a good picture of any of them! They were all living in little houses made of plant debris, and if I tapped on them to ask them to come out, they did a typical Parasteatoda thing: they’d immediately bungee straight down to the ground. They’re conveniently predictable when trying to catch them, but I just wanted to say hello and take a picture.
To see what I mean about the difficulty, I saved one photo of one tucked into a bit of dried flower petal, with just her blurry butt sticking out.

I’ve got 4 of these spider nests tagged now, and I’ll be back tomorrow and will try to get some better pictures. Except I think we’ve got thunderstorms predicted for Sunday…so maybe a little later.

You can see the photos, if you really want to, on Patreon or Instagram, as usual.

We’re all going to come out of this with new phobias

I’m starting to think I never want to be around people again, what with all their filthy, moist exhalations.


Micro droplets suspending in air from MixonK on Vimeo.

On the plus side, I’ve always wanted an excuse to wear a mask and cover this homely face. I look forward to the new support for industries that make fashionable face wear — I would like a formal mask for special occasions, a professional mask for work, and a wild & crazy mask for partying in the streets (alone, of course). I may also need a spider mask for those days I’m focused on arachnids, even though they tend not to sneeze.

My first Raspberry Pi

We put it together today, me and my nerdy daughter and my very excited granddaughter, who had to inspect each of the components.

She had to teach me a little (very little) Python, but we got it working with a little script to take time lapse images. That’s the camera at the top, and the two eyeballs are IR LEDs. The plan is to do a test run when I get back and see if we can record night-time spider activity with it. The spiders are very sneaky, and when I see them during the day they’re usually lounging about, doing little unless some prey falls into their web, but every morning I see the cages more densely matted with cobwebs, so it would be nice to watch them at work.

The images aren’t bad for such a minuscule lens. The test will be to see if I can get enough depth of field to get a sense of their 3-dimensional construction methods.

(If you’re curious, that’s the CanaKit Raspberry Pi 4 4GB Starter Kit and the UNIROI Raspberry Pi Camera Module.)

I puked on Evolutionary Psychology before it was cool to puke on Evolutionary Psychology

I rejected it because it’s panadaptationist nonsense, among other things. But I’m always happy to see more arguments for why it is garbage, such as this criticism from a philosopher.

Evolutionary psychologists’ thought is that, for at least some of our behaviors, they believe that we have—dare I use this term—hard-wired cognitive structures that are operating in all of us contemporary human beings the same way they did for our ancestors on the savannas. The idea is that, in the modern world, we have sort of modern skulls, but the wiring—the cognitive structure of the brain itself—is not being modified, because enough evolutionary time hasn’t passed. This goes for evolutionary functions like mate selection, parental care, predator avoidance—that our brains were pretty much in the same state as our ancestors’ brains. The sameness in how our brains work is on account of genetic selection for particular modules that are still functional in our environment today. [Editor’s note: These “modules” refer to the idea that the brain can be divided up into discrete structures with specific functions.]

The matching problem is really the core issue that evolutionary psychologists have to show that they can meet: that there is really a match between our modules and the modules of the prehistoric ancestors; that they’re working the same way then as now; and that these modules are working the same way because they are descended from the same functional lineage or causal lineage. But I don’t see any way that these charges can be answered.

True, that. But just watch — evolutionary psychologists will rapidly retreat from those core ideas of “environment of evolutionary adaptation” and “modules” to find safety in the uncontroversial idea that the brain evolved.

We still get buckets of baloney about evolution from people who should know better. Have you heard of the pugilism hypothesis? This is the idea that men’s beards evolved to absorb a punch to the jaw. You only have to think about it for a moment to realize that getting socked in the face was a small factor in human evolution — 10,000 years ago, I would have been more concerned about starvation, getting a disease, breaking an arm while hunting, or getting thwocked in the back of the head with a rock by a bad guy. That facial hair might have provided a slight cushion to facial injuries doesn’t seem like the kind of thing for which there was much selection pressure, and I could also sit here and imagine all kinds of drawbacks to furry faces.

But it’s been tested! Except no, it hasn’t.

Because facial hair is one of the most sexually dimorphic features of humans (Homo sapiens) and is often perceived as an indicator of masculinity and social dominance, human facial hair has been suggested to play a role in male contest competition. Some authors have proposed that the beard may function similar to the long hair of a lion’s mane, serving to protect vital areas like the throat and jaw from lethal attacks. This is consistent with the observation that the mandible, which is superficially covered by the beard, is one of the most commonly fractured facial bones in interpersonal violence. We hypothesized that beards protect the skin and bones of the face when human males fight by absorbing and dispersing the energy of a blunt impact. We tested this hypothesis by measuring impact force and energy absorbed by a fiber epoxy composite, which served as a bone analog, when it was covered with skin that had thick hair (referred to here as “furred”) versus skin with no hair (referred to here as “sheared” and “plucked”). We covered the epoxy composite with segments of skin dissected from domestic sheep (Ovis aries), and used a drop weight impact tester affixed with a load cell to collect force versus time data. Tissue samples were prepared in three conditions: furred (n = 20), plucked (n = 20), and sheared (n = 20). We found that fully furred samples were capable of absorbing more energy than plucked and sheared samples. For example, peak force was 16% greater and total energy absorbed was 37% greater in the furred compared to the plucked samples. These differences were due in part to a longer time frame of force delivery in the furred samples. These data support the hypothesis that human beards protect vulnerable regions of the facial skeleton from damaging strikes.

I would concede even before testing it that a layer of hair over the face would reduce the force of impacts to some degree. But that’s not testing an evolutionary hypothesis! You need to show that this ‘padding’ had a measurable effect on survival and reproductive success. They merely looked at one superficial phenomenon and decided that dissipating the force of a punch to the jaw allowed beardy guys to thrive, in a world without the Marquis of Queensbury rules. It seems his beard didn’t save Otzi from the arrow that killed him.

There are a few people — thankfully few — that go wacko over their single comprehensive explanation. Apparently, humans evolved to be boxers.

More broadly, the results of this study add to a growing body of evidence suggesting that specialization for male fighting has played a significant role in the evolution of the musculoskeletal system of humans. For example, the short limbs (Carrier 2007), plantigrade foot posture (Carrier and Cunningham 2017), and bipedal posture of our earliest hominins ancestors (Carrier 2011), and the force–velocity tuning (Carrier et al. 2011) and size (Carrier et al. 2015) of the muscles of the human leg may also be associated with improved fighting performance.

Ugh. Umbrella Hypothesis alert.

What about the fall?

I’m not quite done with grading — genetics is complete! — but yeah, I already have to think about Fall semester? Yikes. I’m expecting a resurgence of the coronavirus this summer that will be worse than what we had in the spring, because we a) don’t have adequate testing, b) don’t have a vaccine, and c) have a country infested with idjits who want to get a haircut no matter how many other people’s lives it puts at risk. Meanwhile, the universities are dithering about what to do. I have no idea what I’m expected to do come September, although we’re kind of mumbling about contingency plans.

This is a fairly clear-eyed view of the immediate future.

Higher education as we know it is approaching economic collapse. I appreciate the frantic gestures college presidents are making to prevent their own campuses from failing. Many intend to open their campuses for the fall term and avoid economic ruin. It is the wrong call.

Even the most optimistic of epidemiologists have two opinions about the remaining months of 2020: mass gatherings should be prohibited, and people over 55 and/or with pre-existing conditions should continue to stay indoors. We also know that individuals under 25 are least likely to become sick with the coronavirus and are most likely to flout requests to stay indoors, wear masks and avoid public places such as beaches and parks.

College presidents are unsure about what to do with their campuses in the fall, and uncertainty breeds anxiety. No one has a crystal ball, but with what we know, what should happen on the nation’s campuses in the fall is increasingly clear. The option of students returning to campus in the fall is not viable, regardless of the economic implications.

The author has some suggestions about what to do if we are open: cancel all those big stadium football games, make special provisions for faculty and students over 55 (we have to teach online, while the younger faculty teach in classes? I think he has an elevated opinion of the safety of young adults), constant testing (we don’t have a reliable, affordable test), and maintain social distancing in the classroom. OK, so I looked at my list of registered students for the Fall to see if that is feasible. Enrollments are down everywhere, right?

I’ll be teaching cell biology, which typically has about 50 students. It’s down a lot right now, with 35 students registered, although it will probably go up a little bit more over the summer. I’ve been assigned a huge lecture hall, so social distancing in class will be easy — I can put them in every 3rd or 4th seat, every other row, and have room left over. Lecture will be easy.

The problem will be labs. I have 3 lab sections for those 35 students, and we generally have students work in groups. That’s not going to work. Making it work would require major restructuring — break up the labs into more independent study sections, so we can separate them more? Even there, any infected students are going to spray fomites all over the microscopes and spectrophotometers. Need I point out, though, this is where the students who will one day be the front line in dealing with future pandemics will get their start?

I imagine our administration is freaking out.

Greater than 5 percent of the more than 4,000 U.S. colleges and universities are likely to close because of falling enrollment, according to Robert Zemsky. Many observers now predict that enrollments will shrink by 15 percent. The pandemic and the Trump administration’s xenophobia alone will shrink foreign student enrollment, especially from China and India, by 25 percent, the American Council on Education has estimated. Meanwhile, some states like New Jersey are already clawing back money from campuses that has been allocated for this fiscal year; next year’s budgets will be worse than the recession in every state. Philanthropic giving will take a nose dive. Summer and auxiliary enterprises will yield next to no additional revenue.

College presidents have a right to be terrified. But opening campuses in the fall is the wrong move if the primary motivation is to avoid bankruptcy. Public health comes first.

Right. Public health must come first. The answer ought to be a massive public investment in educational and medical infrastructure to keep us all limping along until this disease is overcome. Will we get it? No. It’s hard not to feel a sense of impending doom when we witness the government overseeing this disaster.

So, right now I focus on finishing this last semester, which already ended in a colossal pratfall. Once that’s done, maybe I can think about how to manage the next one.

Hey, rigorous training in how to clean and sterilize a workspace would be an appropriate first lab in cell biology, right?