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Putting air filters in classrooms seems to boost student attendance, which may be due to them reducing levels of air pollution, pollen, pathogens or all three

The Naturalistic Fallacy, which most of you surely know, it the erroneous equation of what does exist with what should exist.  Discussed extensively by Hume, it is the false equation of “is” with “ought”. In biology, it takes the form of observing some behavior in animals that is similar to a behavior in humans, and then justifying or saying the human behavior “natural”  or “good” because we see it in other species.

But this is a bad argument, for it cuts both ways. After all, animals show a lot of behavior that would be considered reprehensible or even immoral in humans.  In fact, Joan Roughgarden wrote a book, Evolution’s Rainbow, which describes sex and gender diversity in nature as an explicit way of justifying similar behaviors in humans as good—because they are natural. I reviewed the book for TLS and wrote this bit (review no longer online but I can send a copy).

Coyne, J. A.  2004.  Charm schools. (Review of Evolution’s Rainbow, by Joan Roughgarden). Times Literary Supplement, London. July 30, 2004 (No. 5287), p. 5.

But regardless of the truth of Darwin’s theory, should we consult nature to determine which of our behaviours are to be considered normal or moral? Homosexuality may indeed occur in species other than our own, but so do infanticide, robbery and extra-pair copulation.  If the gay cause is somehow boosted by parallels from nature, then so are the causes of child-killers, thieves and adulterers. And given the cultural milieu in which human sexuality and gender are expressed, how closely can we compare ourselves to other species? In what sense does a fish who changes sex resemble a transgendered person? The fish presumably experiences neither distressing feelings about inhabiting the wrong body, nor ostracism by other fish. In some baboons, the only males who show homosexual behaviour are those denied access to females by more dominant males. How can this possibly be equated to human homosexuality?

The step from “natural” to “ethical” is even riskier. As the philosopher G. E. Moore argued, identifying what is good or right by using any natural property is committing the “naturalistic fallacy”: there is no valid way to deduce “ought” from “is”. If no animals showed homosexual behaviour, would discrimination against gay humans be more justified? Certainly not. Roughgarden’s philosophical strategy is as problematic as her biological one.

Now a 2022 paper in Nature Communications had the potential to demonstrate the same fallacy, but fortunately the authors went to great lengths to avoid that  The same, however, is not true of a new take on this paper in a new article in ZME Science, which gave a précis of the paper and stepped on the Fallacy’s tail.

First the Nature paper itself, which you can access by clicking on the article below, or by reading the pdf here.

It’s a good paper on the evolution and phylogeny of “same-sex sexual behavior” in mammals, which they define as “transient courtship or mating interactions between members of the same sex“.  

Note that it’s “transient,” which explicitly excludes homosexuality, most notably in humans, which is a persistent sexual attraction to members of one’s own biological sex.  This form of transient sexual interaction is surprisingly common—a conservative estimate is 4% of all animal species, and, as the authors say, [includes] “all main groups from invertebrates such as insects, spiders, echinoderms, and nematodes, to vertebrates such as fish, amphibians, reptiles, birds, and mammals.”

Now there are two ways to explain a behavior that seems on its face maladaptive. Why would you engage in sexual behavior that doesn’t involve passing on your genes? One hypothesis is that it’s just a nonadaptive byproduct of other behaviors: a general drive to mate when the appropriate mates aren’t available, or simply mistaken identity.  But the authors investigate two hypotheses that it is adaptive, and give some tentative evidence for that.

First, the results:

• The authors did a comprehensive survey of same-sex behavior (defined above) in 2546 species of mammals, and superimposed species with and without such behavior on their phylogenetic tree. The object was to see how many times the behavior evolved independently, and whether it was present in the common ancestor of a group (and thus could be passed along to its descendants). Here’s one of those phylogenies with the caption. (You needn’t worry about the details or summary, as I’ll give it below).

(from paper) Phylogenetic distribution of the presence of same-sex sexual behaviour in males and females in the subset III (see methods). The state of the mammalian ancestral nodes was assessed using maximum likelihood estimation (black: same-sex sexual behaviour displayed by females; yellow: same-sex sexual behaviour displayed by males; purple: same-sex sexual behaviour displayed by both sexes). The silhouettes of representative mammals (downloaded from http://www.phylopic.org) illustrate the main mammalian clades. They have a Public Domain license without copyright (http://creativecommons.org/licenses/by/3.0).

A summary:

•  The behavior was reported in 261 mammalian species
• Same-sex sexual behavior appears to be equally common in males and females, and the behavior in both sexes tends to be correlated across groups. That is, male and female same-sex behavior is more likely to both appear in the same species than if it either were distributed randomly among groups.
• It was not possible tell, using phylogenetic analysis, whether same-sex behavior was likely to be a trait in the ancestor of all mammals, but was NOT likely to be a trait in the ancestor of all placental mammals.
• The behavior seems to have evolved independently in many lineages, so same-sex sexual behavior seems to be a case of “convergent evolution.”
• The behavior is correlated with whether or not a species is social. If it is social, there’s a significantly higher probability of same-sex sexual behavior. (Remember that this is a correlation and doesn’t imply that sociality prompts the evolution of such behavior. The behavior could simply result from iondividuals in social species being closer to other individuals than those in non-social species.)
• The common ancestor of all primates does seem to have possessed same-sex sexual behavior.

The association of same-sex sexual behavior with sociality leads the authors to conclude that the behavior evolved by natural selection as a way to enforce inter-individual harmony required by sociality. They mention two such advantages:

1.) Same-sex sexual behavior is a way of creating and maintaining social bonds between individuals in a group; it’s a bonding mechanism.
2.) The behavior could also help prevent or resolve conflicts between members of a group, allowing a hierarchy to develop without injury of death to group members.

The authors mention that these effects have been demonstrated in some species like bottlenose dolphins and American bison, but I’m not familiar with this work, and such conclusions seem to me to be extraordinarily difficult to arrive at. However, I’ll take the authors’ word for it.

The authors are, to be sure, careful in their conclusions. First, they note that nonadaptive hypotheses, like “mistaken identity” could also contribute to the behavior.

Second, and the big one, they note that the behavior they studied is not the same as homosexual behavior like we find in humans.  They do add, however, that it humans do show same-sex sexual behavior in humans (I presume they’re referring to “bisexual” people who have sex with both males and females). From the paper:

However, same-sex sexual behaviour is operationally defined here as any temporary sexual contact between members of the same sex2. This behaviour should be distinguished from homosexuality as a more permanent same sex preference, as found in humans. For this reason, our findings cannot be used to infer the evolution of sexual orientation, identity, and preference or the prevalence of homosexuality as categories of sexual beings Nevertheless, even taking into account this cautionary note, by using phylogenetic inference, our study may provide a potential explanation on the evolutionary history of the occurrence of same-sex sexual behaviour in humans.

They may be right, but I think they should have added that even if same-sex sexual behavior was rare or nonexistent in mammals, its existence in humans is not made “ethical” or “natural” in our species. That would be an example of the naturalistic fallacy, and I emphasize that they do not commit it.  I’d would also emphasize, as I did above, that any sexual behavior between consenting human adults is not for us to judge, regardless of whether or not other species show it, and that such behaviors are fine so long as they’re legal. We don’t need to justify same-sex sexual behavior in humans by seeing it elsewhere in nature. But perhaps this stuff doesn’t belong in a scientific paper. But I want to emphasize it here, as I did in my review of Roughgarden’s book.

As I said, the authors don’t commit the naturalistic fallacy, but the new ZME Science paper below comes close to it. Click headline to read:

Up until the end, this article is okay, but then it can’t resist diving into our own species (bolding is mine).

However, the researchers distinguish between SSSB and sexual orientation. While SSSB involves occasional same-sex interactions, sexual orientation encompasses consistent patterns of attraction and identity, particularly prominent in humans.

While SSSB in animals supports the naturalness of such behaviors, human experiences of sexuality include layers of identity, culture, and personal meaning that go beyond biological explanations. Homosexuality in humans often involves stable sexual orientations and relationships, distinct from the transient or context-dependent SSSB observed in some animal species.

Ultimately, the widespread occurrence of SSSB in mammals, especially primates, strongly suggests that such behaviors are natural and adaptive. Normalizing same-sex behavior as a part of this spectrum aligns with both biological evidence and a broader understanding of human social and emotional complexity.

The last paragraph explicitly says that the results show that homosexuality (one of “such behaviors”) is “natural and adaptive”, as are all “same-sex behaviors” in humans.  The Nature paper says nothing of the sort.  The authors of the Nature paper explicitly exclude homosexuality as not a behavior they studied, but ZME Science lumps it in with other same-sex sexual behaviors, dwspite homosexuality being very different from SSSB.

Again, you do NOT need to justify same-sex sexual behavior, whether it be transient or permanent, by finding examples in the natural world. If we didn’t find any other species with homosexual behavior, would that make it wrong or bad in humans? Of course not! “Is” does not equal “ought,” and I’ll add the corollary that “not is” does not equal “not ought”. The Nature paper is valuable it looking at the evolution of a behavior and testing hypotheses about its adaptiveness, but of course adaptiveness or evolution has nothing to do with the ethics of behaviors between consenting human adults.

The global energy system may be faced with an inescapable trade-off between urgently addressing climate change versus avoiding an energy shortfall, according to a new energy scenario tool.

As the second-largest object in the main asteroid belt, Vesta attracts a healthy amount of scientific interest. While smaller asteroids in the belt are considered fragments of collisions, scientists think Vesta and the other three large objects in the belt are likely primordial and have survived for billions of years. They believe that Vesta was on its way to becoming a planet and that the Solar System's rocky planets likely began as protoplanets just like it. But new research is casting doubt on that conclusion.

Reader Debra Coplan made a trip to Baja, and today sends us photos. Her captions and IDs are indented, and you can enlarge the photos by clicking on them.

I had the opportunity to visit the Baja Peninsula this past weekend, and would like to share some of the wonderful vegetation I saw from the that area. We went as far south as the Sonora Desert region to Catavina, east of the Pacific Ocean. Catavina is about 300 miles south of the border.

We had to drive from the north which had Mediterranean desert foliage to the Sonora Desert which had little rain. The Mediterranean desert gets hurricanes which dump water to an area in that more northern part of the desert.

The Mediterranean desert is north of Sonora desert, but they abut next to each other. Sometimes we saw Mediterranean desert on one side of the road and Sonora-type vegetation on the other . A clearer transition between the 2 areas became evident as we went south into drier region: one side being lush with taller plants and the other side dry with low plants.

I am not a biologist, so hopefully I’ve identified the plants correctly.

Boojum Tree – Cirio Idria columnaris

This is an plant endemic to this Catavina area of the desert. It is the signature plant of the region, and can get to 70 feet tall. The flame of leaves on the top are golden like a flame at the top of a candle. See top photo.

The second Boojum had a stalk that was in an area of more water so it looks more lush.  The name Boojum is in reference to Lewis Carroll’s poem, “The Hunting of the Snark”. It is looks a bit like an upside down carrot with a whitish stalk.

On the road on the way out of Catavina we were stopped by the military police checking to make sure we did not steal a Boojum tree to transplant up north. Cardon.  Pachycereus pringleiL

This particular cardon had a genetic mutation so instead of growing up, it grew sideways. The man is about 6’ tall.  I was fascinated by the one limb that wasn’t affected by the mutation.

California penstemon; Penstemon californicus:

I am including this penstemon flower because it was my favorite story. I loved how it gets pollinated. Unfortunately, the plant was down below a steep creek so I did not get a photo.

Various species of bees in the region are guided into the flower by the purple lines pointing the way to the back of the flower. It reminds me of an airplane coming in for a landing.

As the bees go in, the pollen rubs from the antlers (male part) off onto the bee.  You can see the long anthers but unfortunately there was no pollen in this one. The bees then fly off to another penstemon where the pollen interacts with the stigma (female part) deeper in the flower to pollinate.

Nightshade Mariola, Solanum hindsianum

Unfortunately I don’t have a picture of a flower on this plant either,  but was amazed by the pollination story.  This plant had very tiny opening at the end of the yellow anthers. It’s very hard for bees to get into the tiny opening to get the pollen so they use buzz pollination.  The bees grab hold of the yellow anthers and vibrate their bodies, which forces the pollen out and onto their bodies, where it gets distributed.

Hedgehog cactus, Echinocereus:

 

In Catavina, inland from the Pacific Ocean, we visited a cave of the Cochimis, the indigenous inhabitants of this area.

 

A steep 10-minute hike up huge boulders of the Sonora desert reveals a cave with some paintings that were about 4,000 years old.   I have no idea what dyes they used, but heard they were not from plants of this area.

There is the head of a hummingbird in the painting below:

In my previous post I wrote about how we think about and talk about autism spectrum disorder (ASD), and how RFK Jr misunderstands and exploits this complexity to weave his anti-vaccine crank narrative. There is also another challenge in the conversation about autism, which exists for many diagnoses – how do we talk about it in a way that is scientifically accurate, useful, and yet not needlessly stigmatizing or negative? A recent NYT op-ed by a parent of a child with profound autism had this to say:

“Many advocacy groups focus so much on acceptance, inclusion and celebrating neurodiversity that it can feel as if they are avoiding uncomfortable truths about children like mine. Parents are encouraged not to use words like “severe,” “profound” or even “Level 3” to describe our child’s autism; we’re told those terms are stigmatizing and we should instead speak of “high support needs.” A Harvard-affiliated research center halted a panel on autism awareness in 2022 after students claimed that the panel’s language about treating autism was “toxic.” A student petition circulated on Change.org said that autism ‘is not an illness or disease and, most importantly, it is not inherently negative.'”

I’m afraid there is no clean answer here, there are just tradeoffs. Let’s look at this question (essentially, how do we label ASD) from two basic perspectives – scientific and cultural. You may think that a purely scientific approach would be easier and result in a clear answer, but that is not the case. While science strives to be objective, the universe is really complex, and our attempts at making it understandable and manageable through categorization involve subjective choices and tradeoffs. As a physician I have had to become comfortable with this reality. Diagnoses are often squirrelly things.

When the profession creates or modifies a diagnosis, this is really a type of categorization. There are different criteria that we could potentially use to define a diagnostic label or category. We could use clinical criteria – what are the signs, symptoms, demographics, and natural history of the diagnosis in question? This is often where diagnoses begin their lives, as a pure description of what is being seen in the clinic. Clinical entities almost always present as a range of characteristics, because people are different and even specific diseases will manifest differently. The question then becomes – are we looking at one disease, multiple diseases, variations on a theme, or completely different processes that just overlap in the signs and symptoms they cause. This leads to the infamous “lumper vs splitter” debate – do we tend to lump similar entities together in big categories or split everything up into very specific entities, based on even tiny differences?

The more we learn about these burgeoning diagnoses the more the diagnostic criteria might shift away from a purely clinical descriptive one. Perhaps we find some laboratory marker (such as a result on a blood test, or finding on an MRI scan of the brain). What if that marker has an 80% correlation to the clinical syndrome? How do we use that as a diagnostic criterion? The more we learn about pathophysiology, the more these specific biological factors become part of the diagnosis. Sometimes this leads to discrete diagnoses – such as when it is discovered that a specific genetic mutation causes a specific disease. The mutation becomes the diagnosis. But that is often not the case. The game changes again when treatments become available, then diagnostic criteria tends to shift toward those that predict response to treatment.

One question, therefore, when determining the best way to establish a specific diagnostic label is – what is your purpose? You might need a meaningful label that helps guide and discuss basic science research into underlying phenomena. You may need a diagnosis that helps predict natural history (prognosis), or that guides treatment, or you may need a box to check on the billing form for insurance, or you may need a diagnosis as a regulatory entity (for FDA approval for a drug, say).

ASD has many of these issues. Researchers like the spectrum approach because they see ASD as different manifestations of one type of underlying neurological phenomenon. There are many genes involved, and changes to the pattern of connectivity among brain cells. Clinicians may find this lumper approach a double-edged sword. It may help if there is a single diagnostic approach – scoring on standardized tests of cognitive, motor, language and social functioning, for example. But it also causes confusion because one label can mean such dramatically different things clinically. The diagnosis is also now often attached to services, so there is a very practical aspect to it (and one major reason why the diagnosis has increased in recent years – it gets you services that a less specific diagnosis might not).

Now let’s go to the social approach to the ASD diagnosis. The purely scientific approach is not clean because “science” can refer to basic science or clinical science, and the clinical side can have multiple different approaches. This means science cannot currently solve all the disputes over how the ASD diagnosis is made and used in our society. It’s ambiguous. One aspect of the debate is whether or not ASD should be considered a disease, a disorder, or just a spectrum of natural variation within the human species. Anti-vaxxers want to see is as a disease, something to be prevented and cured. This approach also tends to align better with the more disabled end of the spectrum. At the high functioning end of the spectrum, the preference is to look at ASD as simply atypical, and not inherently inferior or worse than neurotypicals. The increased challenges of being autistic are really artificially created by a society dominated by neurotypicals. There are also in fact advantages to being neuroatypical in certain areas, such as jobs like coding and engineering. Highly sociable people have their challenges as well.

Here’s the thing – I think both of these approaches can be meaningful and useful at the same time. First, I don’t think we should shy away from terms like “profound” or “severe”. This is how neuroscience generally works. Everyone does and should have some level of anxiety, for example. Anxiety is adaptive. But some people have “severe” anxiety – anxiety that takes on a life of its own, or transitions from being adaptive to maladaptive. I don’t want to minimize the language debate. Words matter. Sometimes we just don’t have the words that mean exactly what we need them to mean, without unwanted connotations. We need a word that can express the spectrum without unwanted assumptions or judgement. How about “extreme”? Extreme does not imply bad. You can be extremely athletic, and no one would think that is a negative thing. Even if autism is just atypical, being extremely autistic implies you are at one end of the spectrum.

Also, as with anxiety, optimal function is often a mean between two extremes. No anxiety means you take unnecessary risks. Too much anxiety can be crippling. Having mildly autistic features may just represent a different set of neurological tradeoffs, with some advantages and some challenges, and because it is atypical some accommodation in a society not optimized for this type. But as the features get more extreme, the downsides become increasingly challenging until you have a severe disability.

This reminds me also of paranoia. A little bit of paranoia can be seen as typical, healthy, and adaptive. A complete absence of any suspiciousness might make someone naive and vulnerable. People with above average paranoia might not even warrant a diagnosis – that is just a personality type, with strengths and weaknesses. But the more extreme you get, the more maladaptive it becomes. At the extreme end it is a criterion for schizophrenia.

Or perhaps this is all just too complex for the public-facing side of this diagnosis (regulation, public education, etc). Perhaps we need to become splitters, and break ASD up into three or more different labels. Researchers can still have and use a technical category name that recognizes an underlying neurological commonality, but that does not need to be inflicted on the public and cause confusion. Again – there is no objective right or wrong here, just different choices. As I think I amply demonstrated in my prior post, using one label (autism) causes a great deal of confusion and can be exploited by cranks. What often happens, though, is that different groups make up the labels for their own purposes. When researchers make the labels, they favor technical basic-science criteria. When clinicians do, they favor clinical criteria. When regulators do, they want nice clean categories.

Sometimes all these levels play nicely together. With ASD I feels as if they are in conflict, with the more research-based labels holding sway and causing confusion for everyone else.

At the same time there is a conflict between not imposing inaccurate and unnecessary judgement on a label like autism, while at the same time recognizing that can come with its own challenges that need just awareness at the mildest end of the spectrum, accommodation for those who experience challenges and have needs, and then actual treatment (if possible) at the more extreme end. These do not need to be mutually exclusive.

I do think we are evolving in a good direction, with more thoughtful diagnostic labels that explicitly serve a purpose without unnecessary assumptions or judgement. We may not be entirely there yet, but it’s a great conversation to have.

The post The Other End of the Autism Spectrum first appeared on NeuroLogica Blog.

Super mushrooms are claimed by some to provide vague health benefits beyond their known nutritional values.

Learn about your ad choices: dovetail.prx.org/ad-choices

Our current Medical Establishment doesn't seem to grasp that they are no longer just Fox News and Twitter celebrities who can comment from the sidelines as if they were passive observers.

The post Goodbye to the Novavax Vaccine? Our Flailing Medical Establishment Rejects Medical Freedom and Refuses to Fund Gold-Standard Science. first appeared on Science-Based Medicine.

What will a human experience while standing on the surface of Saturn’s largest moon, Titan, even with the protection of a pressurized spacesuit? This is what a recent study presented at the 56th Lunar and Planetary Science Conference hopes to address as William O’Hara, who is the Executive Director of Explore Titan investigated what physical attributes a human will experience when standing on Titan’s surface. This study has the potential to help scientists, engineers, mission planners, and the public better understand the risks associated with sending humans to far-off worlds for long periods of time and how to develop technologies to mitigate these risks.

Star birth is a process hidden inside dense crèches of gas and dust. Yet, if you know what to look for, you can see the products of this essential cosmic process across the sky. The Circinus West molecular cloud is a starbirth crèche some 2,500 light-years away. It boasts everything from dark nebulae to protostellar objects and newborn stars to the faint ghosts of stars that have already died.

Scientists have developed a highly sensitive method to detect illegal opioids and a veterinary sedative in Australia's wastewater system, providing a vital early warning tool to public health authorities.

It is now possible to obtain three-dimensional, high-resolution images of enzyme activity in tissue samples or whole organs -- thanks to probe molecules that anchor fluorescent dyes within tissue as they are activated by enzymes. The organ being mapped is made transparent by a clearing process. This allowed for visualization of differences in aminopeptidase N activity and the effects of inhibitors in mouse kidneys.

Astrophysicists have discovered a potentially star-forming cloud that is one of the largest single structures in the sky and among the closest to the sun and Earth ever to be detected. The scientists have named the molecular hydrogen cloud 'Eos,' after the Greek goddess of mythology who is the personification of dawn.

Metal oxyhydroxides are nanoparticles with wide industrial applications, but determining their exact structure is often challenging. Recently, a research team has developed an advanced imaging method called 'lattice correlation analysis' to reveal the detailed 3D atomic structure of titanium oxyhydroxide nanoparticles. By leveraging data-driven insights, this method unlocks the crystal attributes without causing any damage, thus marking a milestone in the study of sensitive nanomaterials.

To provide the right treatment for MS, it is important to know when the disease changes from relapsing-remitting to secondary progressive, a transition that is currently recognized on average three years too late. Researchers have now developed an AI model that can determine with 90 per cent certainty which variant the patient has.

Multipath interference disrupts wireless signals, causing issues like TV ghosting and fading. Now, researchers have developed a passive metasurface that overcomes traditional filtering limits. Using a time-varying interlocking mechanism with field-effect transistors, it transmits the first signal while blocking delayed ones from other angles -- without power or processing. This innovation enables low-cost, reliable wireless communication, which is ideal for IoT applications and environments prone to interference.

Multipath interference disrupts wireless signals, causing issues like TV ghosting and fading. Now, researchers have developed a passive metasurface that overcomes traditional filtering limits. Using a time-varying interlocking mechanism with field-effect transistors, it transmits the first signal while blocking delayed ones from other angles -- without power or processing. This innovation enables low-cost, reliable wireless communication, which is ideal for IoT applications and environments prone to interference.

Combinatorial optimization problems (COPs) arise in various fields such as shift scheduling, traffic routing, and drug development. However, they are challenging to solve using traditional computers in a practical timeframe. Alternatively, annealing processors (APs), which are specialized hardware for solving COPs, have gained significant attention. They are based on the Ising model, in which COP variables are presented as magnetic spins and constraints as interactions between spins. Solutions are obtained by finding the spin state that minimizes the energy of the system.

Combinatorial optimization problems (COPs) arise in various fields such as shift scheduling, traffic routing, and drug development. However, they are challenging to solve using traditional computers in a practical timeframe. Alternatively, annealing processors (APs), which are specialized hardware for solving COPs, have gained significant attention. They are based on the Ising model, in which COP variables are presented as magnetic spins and constraints as interactions between spins. Solutions are obtained by finding the spin state that minimizes the energy of the system.

A squishy, layered material that dramatically transforms under pressure could someday help computers store more data with less energy. That's according to a new study that shows a hybrid zinc telluride-based material can undergo surprising structural changes when squeezed together like a molecular sandwich.