Science

Researchers have developed silk iron microparticles (SIMPs) -- magnetic, biodegradable carriers designed to deliver therapies directly to disease sites like aneurysms or tumors. The particles are created by chemically bonding iron oxide nanoparticles to regenerated silk fibroin using glutathione, enhancing their magnetic responsiveness while maintaining biocompatibility. These nanoscale carriers, roughly one-hundred-thousandth the width of a human hair, can potentially be guided externally to precise locations in the body. The platform enables localized delivery of therapeutic agents such as extracellular vesicles, regenerative factors, or drugs, offering a minimally invasive approach to treating conditions like abdominal aortic aneurysms and expanding the potential for targeted therapies in regenerative medicine.

For the first time, researchers can study the microstructures inside metals, ceramics and rocks with X-rays in a standard laboratory without needing to travel to a particle accelerator, according to engineers.

Traditional methods of looking into quantum systems often require immense resources. Researchers have now developed a new technique that allows scientists to extract essential information more efficiently and accurately.

Traditional methods of looking into quantum systems often require immense resources. Researchers have now developed a new technique that allows scientists to extract essential information more efficiently and accurately.

Getting missions to land successfully on the Moon has been difficult. Recent missions, such as IM-1 and IM-2, which the private company Intuitive Machines completed, have been qualified successes at best, with both landers settling at unintended angles and breaking parts of them off along the way. Such experiences offer excellent learning opportunities, though, and NASA is confident that a third time might be a charm for a flawless mission. There will be a lot riding on IM-3, the third Commercial Lunar Payload Services (CLPS) mission, including a set of rovers and ground station for a NASA experiment called the Cooperative Autonomous Distribution Robotic Exploration (CADRE), which recently passed its Verification and Validation (V&V) test for one of it's most essential parts. This software architecture handles tasks for each rover and binds them into a cohesive whole.

A rare stellar occultation, which happens only once every 30 years, allowed astronomers to observe Uranus and learn more about the composition of its atmosphere and rings.

Users of the r/ChangeMyView subreddit have expressed outrage at the revelation that researchers at the University of Zurich were secretly using the site for an AI-powered experiment in persuasion

The enigmatic Y chromosome has a tendency to disappear from cells with age. Now, research is revealing the long-term impacts this can have on disease risk and life expectancy

Researchers have developed a foolproof recipe for cacio e pepe, based on their findings studying the physics of mixing cheese in water and determining the mechanism that causes the cheese sauce to go from creamy to clumpy. The team found that a 2%-3% starch-to-cheese ratio produced the smoothest, most uniform sauce; they recommend using powdered starch, rather than relying on an unknown amount of starch in pasta water.

One of the most famous findings in physics could be wrong – the double-slit experiment was long thought to confirm that light can be a wave, but its results can be fully explained using only quantum particles

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:

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.