Science

Our Solar System is currently passing through the Local Interstellar Cloud, a region of highly diluted gas and dust between the stars. On its path, Earth continuously accumulates iron-60, a rare radioactive isotope of iron produced in stellar explosions. This has now been confirmed by an international research team led by the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) through the analysis of Antarctic ice tens of thousands of years old. From the steady but time-varying influx, the researchers conclude that the radioactive isotope has been stored within the cloud since a long-past stellar explosion.

Asteroid mining seems simple in theory. A spacecraft flies up to a giant rock in space, scoops out some material, and either processes it on site or returns it back to a huge central processing facility. But in practice, it is certainly not that simple, and a new paper from some Spanish researchers, available in pre-print form on arXiv, showcases one of the reasons why - many small asteroids are spinning ridiculously fast.

Maui in Hawaii experienced some of the worst wildfires in US history in 2023. Amid concerns of a PTSD epidemic, flotation tanks are being deployed to the island to help restore people's mental health

Maui in Hawaii experienced some of the worst wildfires in US history in 2023. Amid concerns of a PTSD epidemic, floatation tanks are being deployed to the island to help restore people's mental health

How can astronomers observe ancient galaxies when they're so challenging to resolve? By looking at a whole bunch of them at once in a single spectral line and seeing how it changes over time. That's what a new instrument called the Tomographic Ionized-carbon Mapping Experiment (TIME) does.

Scientists recently gathered for a conference called Love, Actually and in Theory, but didn't settle on a definition of the topic at hand

Work, illness, divorce: life is riddled with stressors out of your control. But research is revealing new ways to cope with these challenges and find hope instead of despair

Right now I’m reading Steve Stewart-Williams’s new book: A Billion Years of Sex Differences: How Evolution Shaped the Minds of Men and Women. It is neither a pure blank-slate social-constructivist book nor a hereditarian, genetic-deterministic book, but takes an evidence-based middle ground, asking to what extent behaviors and mindset are molded by evolution and to what extent social conditioning plays a role.  I won’t give a take on the book as I’m not yet finished, but it does make many arguments I’m familiar with.  One of these is the familiar and well-documented claim that, based on different degrees of parental investment, men concentrate more than women on beauty when looking for a mate, while women are less interested in appearance than are men but more interested in paternal behavior, status, and wealth of a prospective mate. These are not absolute differences, of course: many men want women who will invest a lot in their offspring (we are, after all, generally monogamous), and many women want men who are pleasing to the eye. This is a difference in average preferences, not absolute ones characterizing all individuals.

Although some of this average sex difference in behavior may reflect social conditioning, its evolutionary background is likely based in part on the differential investment between the sexes in offspring: although many societies are polyandrous and monogamous, on average males still have a potentially larger number of offspring than do females. This appears to be true in many societies, as well as in our closest relatives, the apes and in most species of animals. Women, who by virtue of their reproduction (as well as by both the evolutionary and social impetus to do most of the childcare) need fathers who will do their share of parental duties and provide for the offspring.  And of course men do share some of those duties, but are also more interested in casual sex and adultery—a way to spread more of their genes when they don’t invest as much in offspring.

If you want the evidence for this, read Stewart-Williams’s book or the references he cites.

Why am I pondering this? Because when I went to the library the other day, I caught a glimpse of myself in the entry door and thought, “Geez, look at that ugly old man!”  Whatever attractive physical features I once had—and I was never close to being a Robert Redford—have vanished, carried away by time’s wingéd chariot.  Women, too, worry about ageing, and are even more concerned about it because of a key difference between men and women: as women get older and become unable to reproduce, they become less desirable faster than do men.  A man can have offspring even in his eighties, while in their early fifties most women hit menopause, which means no more kids. Since men have largely evolved to be physically attracted to women who can give them children, women try harder than do men to retain the signs of youth: hair color, plastic surgery, botox, and the like. On average, they try harder to retain physical attractiveness because it is that rather than status that is a dominant way of attracting partners—and most people want a partner.

Which brings up a tangential point: what about gay men and women?  I don’t know their preferences but it would be interesting to study (and I’m sure people have) whether men attracted to other men for lasting partnerships are less concerned with looks than are women attracted to other women for partnerships.

Back to the point, which is this. It is my theory, which is mine (and likely many other people’s) that there is really no objective difference in physical attractiveness with age, in either men or women.  Old men and women look different from their younger selves (I now refrain from looking in mirrors), but the beauty associated with youth and the loss in attractiveness associated with age are not anything objective (beauty never is, of course).  We are simply evolved to think that those features associated with having more offspring on us are more “beautiful”, as those mindsets are the ones promoted by natural selection. This explains why women are more concerned with the physical ravages of time then are men, for their physical attractiveness to the other sex wanes faster with time. I’ve often heard older actresses say that by the time they hit forty, Hollywood no longer wants them, while that doesn’t happen so much with male actors.  Why is this difference retained past the age of reproduction in women? I suppose it’s because it’s largely innate and most women didn’t live past menopause during most of our evolution.

Thus beauty is in the eye of the beholder: it is subjective, like all standards of beauty, but the subjectivity is molded in certain directions by natural selection.

I am not, of course, saying that this is good—only that much of it is natural. I do not want to commit the naturalistic fallacy here, but simply consider what aspects of our minds and behaviors might be based on genes, to what extent, and whether those evolutionary bits have been molded by natural selection.

This parallels a point I’ve made before: other aspects of our senses, like tastes, are clearly molded by natural selection.  I have said, for example, that to a vulture rotten meat tastes as good as an ice-cream sundae does to us.  Animals have evolved to search for food that tastes good because, over time, our senses evolve to find the food we need to grow and reproduce to be tasty. In other words, natural selextion has molded our taste buds and our brains so we prefer what is nutritious and fosters reproduction.  This can be hijacked: we now eat too many fats and sweets because those substances were desirable to our ancestors as they were rare but promoted reproduction.  Now they no longer do so because of the surfeit of “bad” food on tap.  But our taste buds haven’t yet caught up to our health.

Why do feces and vomit repel us, smelling foul? It’s very likely that these substances were evolutionarily associated with the spread of disease, and so we evolved smell-detectors that find them repugnant. After all, dung beetles love the odor of feces!

I’ll draw one more parallel here. Anybody who thinks about it seriously must admit that male orgasms, intricate and immensely pleasurable physiological mechanisms associated with ejaculation, have evolved as a way of promoting reproduction (the evolutionary basis of female orgasms is more speculative, but there is no shortage of adaptive hypotheses).  Orgasms are a way of getting men to produce offspring, just as sweetness is a way of getting us to eat sugar. And, like eating too many sweets, orgasms can be hijacked—severed from their reproductive function by condoms, chemicals, or medication. Organizations like the Catholic Church have tried mightily to try to reconnect sex and reproduction, but it is largely in vain.

I have undoubtedly written this too fast, as I just had some thoughts and wanted to get them down on paper before I forget them. I’ve considered that I’m trying to dispel my idea that I’m unattractive, and in so doing thought about physical attraction in general. And yes, I’m also reading Stewart-Williams’s book, which considers in detail this and other aspects of human (and animal) mentation and behavior.

Once you get an evolutionary mindset, all sorts of behaviors now become more interesting. That doesn’t mean we should make up adaptive stories and consider those stories to be true, but neither should we ignore possible evolutionary explanations. To explain the evolutionary basis of human behaviors and minds will be hard, as most of them evolved in the unrecoverable distant past—in our ancestors.  But some of the explanations are testable, and here I must stop.

Run Hawking's machinery and out pops something startling: the most likely universe looks an awful lot like ours, complete with inflation, a low-entropy beginning, and an arrow of time. All of cosmology, falling out for free. Almost.

We may be getting better images of the Milky Way's supermassive black hole in the future. Astronomers used 10 years of observations of a distant blazar to detect turbulence in the Milky Way's interstellar medium. This turbulence makes images of Sagittarius A-star blurry.

Why have so many people become fixated on protein? Donald Layman is one of the people behind the research showing the benefits of getting more protein in your diet, but he thinks things have gone too far and wants to set the record straight

The Traveling Salesman is a classic problem in mathematics that requires a solution to the most efficient path to take to visit a given number of cities in the least amount of time. But scale this relatively simple concept up to space travel and the calculation becomes much more complex. Instead of visiting a stationary spot on Earth, when calculating the most efficient path to visit asteroids you must account for the fact they are traveling tens of thousands of miles an hour, and their exact position will change based on when a spacecraft leaves. This is known as the Asteroid Routing Problem, and a new paper from a group of Canadian and European researchers lays out a framework that can find the exact solution to any particular combination of asteroids to be visited.

A little-known strain of Ebola virus is behind an ongoing health emergency, prompting researchers to call for the acceleration of vaccine candidates against such infections

We think of our body clock ticking over on a 24-hour cycle, but evidence is growing that it has seasonal rhythms, which could affect our response to vaccines

Time might be even stranger than Einstein imagined. Physicists are now exploring the possibility that a single clock could exist in a quantum superposition, ticking both faster and slower at the same time — almost like Schrödinger’s cat being both alive and dead simultaneously. Using incredibly precise atomic clocks and cutting-edge quantum technologies, researchers believe they may soon be able to test this bizarre prediction in the lab for the first time.

The floating ice shelf of world’s widest glacier – Thwaites glacier in Antarctica – is detaching, with worrying implications for global sea-level rise

Inside some very special black holes, there may be a boundary called a Cauchy horizon. Columnist Leah Crane explores the place beyond which physics breaks and anything is possible

I'm on vacation this week and decided to repost a 2018 article that I had written for my other blog (but never published on SBM) that's oddly relevant to the SBM post last week about that awful NYT acupuncture article. Meet the introduction of the "interstitium" in acupuncture, complete with a major Deepak Chopra connection!

The post A blast from the past: The “interstitium,” the inspiration for that recent awful NYT acupuncture article first appeared on Science-Based Medicine.

Scientists at the University of Cambridge have achieved what was once considered impossible by electrically powering insulating nanoparticles to create a completely new kind of LED. Using tiny organic “molecular antennas,” the team found a way to funnel energy into materials that normally cannot conduct electricity, producing ultra pure near infrared light with remarkable efficiency.

Scientists at the University of Cambridge have achieved what was once considered impossible by electrically powering insulating nanoparticles to create a completely new kind of LED. Using tiny organic “molecular antennas,” the team found a way to funnel energy into materials that normally cannot conduct electricity, producing ultra pure near infrared light with remarkable efficiency.