Science

Well, I’ll treat you to one more item about indigenous knowledge in New Zealand, this time when it clashes with modern science! It turns out that the Māori are beefing about there being too many satellites in the sky, and beefing for two reasons. First, this raises the possibility that the night sky might be changed, making it lighter, and that might make celestial navigation more difficult. Not that the Māori rely on that any more (actually, their Polynesian and SE Asian ancestors developed it), but their historical practice from hundreds of years ago might be made more difficult.

Second, the satellites are somehow said to interfere with a Māori ritual in which the steam from cooked food is allowed to float up toward the stars. (The ritual arose to give thanks for a good harvest.)  It is not clear to me how satellites would interfere with that, so you’ll have to ask the Māori.

Click below to read the excerpt from Stuff, a New Zealand news site:

Here’s the beefing about the ceremony (I’ve added translations):

A Māori scientist has warned our skies could become clogged with up to 100,000 satellites in the next five years – threatening thousands of years of Māori knowledge in the process.

The pollution could get so bad that stars seen by Māori ancestors would no longer be visible to the naked eye.

Elon Musk’s Starlink satellites have already interfered with a tuku wairua [food/steam] ceremony during Matariki, when whānau [members of a family group] who have died are released to the stars; while satellite proliferation threatens traditional waka hourua navigation [celestial navigation using double-hulled canoes].

Scientist, and Indigenous astronomy expert Te Kahuratai Moko-Painting is part of Sustainable Space – a group seeking to save Earth’s lower orbit, under 2000km, from uncontrolled development.

Moko-Painting often shows up in similar items, for he’s quite a vociferous activist.

Moko-Painting said about 15,000 satellites have been sent into space since the 1950s – about 7000 of those are still functional, and about 10,000 are still in space.

“Between 2022 when these estimates were made, and 2030, it’s estimated that we’ll have between 60,000 to 100,000 satellites in orbit.”

He said the about-3000 Starlink satellites in orbit were “already causing issues”.

. . . He got involved in the issue after the first Matariki public holiday in 2022, when he joined his wife’s whānau at Waahi Pā in Huntly for the hautapu (feeding the stars with an offering of kai [food].

“And just as we were doing our tuku wairua, just as we were sending on those who had passed on from that year, we had 21 Starlink satellites cutting through, right past the path of Matariki [the Pleiades star cluster.”

Apparently people thought that this was the stars’ response to the ceremony, and was propitious, but Moko-Painting—who admits that Starlink is important in communicating with rural communities—still has a beef:

“And those who knew would just say ‘no, that’s actually this man who loves the technology for launching satellites but makes them far too bright’ … and he does them in this line in an eye-catching kind of way, and that’s completely unregulated.”

I doubt that people will stop launching satellites because it somehow interferes with this ceremony. But wait! There’s more! As I said, there’s a possibility that too many satellites may interfere with celestial navigation, which only a few Māori still practice. But this is only a hypothesis, and hasn’t been shown, mainly because only a few stalwarts still use celestial navigation, and only as a way to keep alive that ancestral skill:

Even in the middle of the Pacific Ocean on a waka hourua, double-hulled waka used for voyaging, the night sky is 10% brighter than it used to be, Moko-Painting said. “So one could argue that 10% of what our tūpuna could see with their eyes while navigating is no longer visible to us.”

Master navigator Jack Thatcher has travelled tens of thousands of kilometres on waka hourua, as a guiding light that keeps his crews alive.

The Pacific covers a third of the planet. Thatcher’s journeys – using only stars, ocean swells and birds as guides – include a 3200km trip from Aotearoa to Rarotonga, which is only 67km wide.

. . . Having 100,000 satellites in orbit might be good for “pinpoint accuracy” all around the world, but those who rely on the stars for guidance won’t know which is a satellite and which isn’t.

“They’ll obliterate most of the patterns that we all depend on to help us find our way.”

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He said the satellites were already being discussed in the voyaging community. Light pollution wasn’t the only problem – “eventually they’ll be rubbish”, Thatcher said.

“We’re entering that zone of global extinction, because we’ve polluted our planet, now we want to pollute our heavens.”

While the technology might be used instead to navigate the oceans, “that’s not the point”, he said.

“Indigenous knowledge is something that is a self-determination thing.”

It’s not clear to me, though, that if the night sky is 10% brighter than before, this would somehow efface or even impede celestial navigation. They give no evidence, but some want to kvetch about it anyway, because it apparently erases the achievements of the Māori’s ancestors (not the Māori themselves):

Māori know who they are because of their ancestors’ achievements. “And now you’re going to take that all away from us.”

The first waka [canoe] in this country used navigation knowledge that ancestors accrued over millennia, Thatcher said – travelling from Southeast Asia to Aotearoa almost 6000 years later.

Essentially, he said, if you can no longer navigate the oceans through the stars “it becomes book knowledge only”.

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“Indigenous identity helps people to be who they are and enables them to be proud of who they are, because of their ancestral knowledge that they still hold on to.”

The whole idea of keeping indigenous knowledge alive was that “we’re not dependent on any technology”.

So Moko-Painting has joined a group of scientists calling for holding back on launching satellites.  The article ends abruptly:

SpaceX, which operates Starlink, did not reply to queries at time of publication.

The problem with all this is that these two problems haven’t been demonstrated. The navigation impediment is a theoretical possibility and won’t be known until people like Thatcher try it.  Since they can still do it successfully, even with all those satellites up there, I think this is not a serious concern. As for the satellites interfering with the smoke rising to the stars, that is pure superstition and doesn’t command concern from any rational person.

This is admittedly a provocative title coming from a particle physicist, and you might think it tongue-in-cheek. But it’s really not.

We live in a cosmos with quantum physics, relativity, gravity, and a bunch of elementary fields, whose ripples we call elementary particles. These elementary “particles” include objects like electrons, photons, quarks, Higgs bosons, etc. Now if, in ordinary conversation in English, we heard the words “elementary” and “particle” used together, we would probably first imagine that elementary particles are tiny balls, shrunk down to infinitesimal size, making them indivisible and thus elementary — i.e., they’re not made from anything smaller because they’re as small as could be. As mere points, they would be objects whose diameter is zero.

But that’s not what they are. They can’t be.

I’ll tell this story in stages. In my last post, I emphasized that after the Newtonian view of the world was overthrown in the early 1900s, there emerged the quantum physics of the 1920s, which did a very good job of explaining atomic physics and a variety of other phenomena. In atomic physics, the electron is indeed viewed as a particle, though with behavior that is quite unfamiliar. The particle no longer travels on a path through physical space, and instead its behavior — where it is, and where it is going — is described probabilistically, using a wave function that exists in the space of possibilities.

But as soon became clear, 1920s quantum physics forbids the very existence of elementary particles.

In 1920s Quantum Physics, True Particles Do Not Exist

To claim that particles do not exist in 1920s quantum physics might seem, at first, absurd, especially to people who took a class on the subject. Indeed, in my own blog post from last week, I said, without any disclaimers, that “1920s quantum physics treats an electron as a particle with position x and momentum p that are never simultaneously definite.” (Recall that momentum is about motion; in pre-quantum physics, the momentum of an object is its mass m times its speed v.) Unless I was lying to you, my statement would seem to imply that the electron is allowed to have definite position x if its momentum p is indefinite, and vice versa. And indeed, that’s what 1920s quantum physics would imply.

To see why this is only half true, we’re going to examine two different perspectives on how 1920s quantum physics views location and motion — position x and momentum p.

1. There is a perfect symmetry between position and momentum (today’s post)
2. There is a profound asymmetry between position and momentum (next post)

Despite all the symmetry, the asymmetry turns out to be essential, and we’ll see (in the next post) that it implies particles of definite momentum can exist, but particles of definite position cannot… not in 1920s quantum physics, anyway.

The Symmetry Between Location and Motion

The idea of a symmetry between location and motion may seem pretty weird at first. After all, isn’t motion the change in something’s location? Obviously the reverse is not generally true: location is not the change in something’s motion! Instead, the change in an object’s motion is called its “acceleration” (a physics word that includes what in English we’d call acceleration, deceleration and turning.) In what sense are location and motion partners?

The Uncertainty Principle of Werner Heisenberg

In a 19th century reformulation of Newton’s laws of motion that was introduced by William Rowan Hamilton — keeping the same predictions, but rewriting the math in a new way — there is a fundamental symmetry between position x and momentum p. This way of looking at things is carried on into quantum physics, where we find it expressed most succinctly through Heisenberg’s uncertainty principle, which specifically tells us that we cannot know a object’s position and momentum simultaneously.

This might sound vague, but Heisenberg made his principle very precise. Let’s express our uncertainty in the object’s position as Δx. (Heisenberg defined this as the average value of x2 minus the squared average value of x. Less technically, it means that if we think the particle is probably at a position x0, an uncertainty of Δx means that the particle has a 95% chance of being found anywhere between x0-2Δx and x0+2Δx.) Let’s similarly express our uncertainty about the object’s momentum (which, again, is naively its speed times its mass) as Δp. Then in 1920s quantum physics, it is always true that

• Δp Δx > h / (4π)

where h is Planck’s constant, the mascot of all things quantum. In other words, if we know our uncertainty on an object’s position Δx, then the uncertainty on its momentum cannot be smaller than a minimum amount:

• Δp > h / (4π Δx) .

Thus, the better we know an object’s position, implying a smaller Δx, the less we can know about the object’s momentum — and vice versa.

This can be taken to extremes:,

• if we knew an object’s motion perfectly — if Δp is zero — then Δx = h / (4π Δp) = infinity, in which case we have no idea where the particle might be
• if we knew an object’s location perfectly — if Δx is zero — then Δp = h / (4π Δx) = infinity, in which case we have no idea where or how fast the particle might be going.

You see everything is perfectly symmetric: the more I know about the object’s location, the less I can know about its motion, and vice versa.

(Note: My knowledge can always be worse. If I’ve done a sloppy measurement, I could be very uncertain about the object’s location and very uncertain about its location. The uncertainty principle contains a greater-than sign (>), not an equals sign. But I can never be very certain about both at the same time.)

An Object with Known Motion

What does it mean for an object to have zero uncertainty in its position or its motion? Quantum physics of the 1920s asserts that any system is described by a wave function that tells us the probability for where we might find it and what it might be doing. So let’s ask: what form must a wave function take to describe a single particle with perfectly known momentum p?

The physical state corresponding to a single particle with perfectly known momentum P0 , which is often denoted |P0>, has a wave function

times an overall constant which we don’t have to care about. Notice the ; this is a complex number at each position x. I’ve plotted the real and imaginary parts of this function in Fig. 1 below. As you see, both the real (red) and imaginary (blue) parts look like a simple wave, of infinite extent and of constant wavelength and height.

Figure 1: In red and blue, the real and imaginary parts of the wave function describing a particle of known momentum (up to an overall constant). In black is the square of the wave function, showing that the particle has equal probability to be at each possible location.

Now, what do we learn from the wave function about where this object is located? The probability for finding the object at a particular position X is given by the absolute value of the wave function squared. Recall that if I have any complex number z = x + i y, then its absolute value squared |z2| equals |x2|+|y2|. Therefore the probability to be at X is proportional to

(again multiplied by an overall constant.) Notice, as shown by the black line in Fig. 1, this is the same no matter what X is, which means the object has an equal probability to be at any location we choose. And so, we have absolutely no idea of where it is; as far as we’re concerned, its position is completely random.

An Object with Known Location

As symmetry requires, we can do the same for a single object with perfectly known position X0. The corresponding physical state, denoted |X0>, has a wave function

again times an overall constant. Physicists call this a “delta function”, but it’s just an infinitely narrow spike of some sort. I’ve plotted something like it in Figure 2, but you should imagine it being infinitely thin and infinitely high, which obviously I can’t actually draw.

This wave function tells us that the probability that the object is at any point other than X0 is equal to zero. You might think the probability of it being at X0 is infinity squared, but the math is clever and the probability that it is at X0 is exactly 1. So if the particle is in the physical state |X0>, we know exactly where it is: it’s at position X0.

Figure 2: The wave function describing a particle of known position (up to an overall constant). The square of the wave function is in black, showing that the particle has zero probability to be anywhere except at the spike. The real and imaginary parts (in red and blue) are mostly covered by the black line.

What do we know about its motion? Well, we saw in Fig. 1 that to know an object’s momentum perfectly, its wave function should be a spread-out, simple wave with a constant wavelength. This giant spike, however, is as different from nice simple waves as it could possibly be. So |X0> is a state in which the momentum of the particle, and thus its motion, is completely unknown. [To prove this vague argument using math, we would use a Fourier transform; we’ll get more insight into this in a later post.]

So we have two functions, as different from each other as they could possibly be,

• Fig. 1 describing an object with a definite momentum and completely unknown position, and
• Fig. 2 describing an object with definite position and completely unknown momentum.

CAUTION: We might be tempted to think: “oh, Fig. 1 is the wave, and Fig. 2 is the particle”. Indeed the pictures make this very tempting! But no. In both cases, we are looking at the shape of a wave function that describes where an object, perhaps a particle, is located. When people talk about an electron being both wave and particle, they’re not simply referring to the relation between momentum states and position states; there’s more to it than that.

CAUTION 2: Do not identify the wave function with the particle it describes!!! It is not true that each particle has its own wave function. Instead, if there were two particles, there would still be only one wave function, describing the pair of particles. See this post and this one for more discussion of this crucial point.

Objects with More or Less Uncertainty

We can gain some additional intuition for this by stepping back from our extreme |P0> and |X0> states, and looking instead at compromise states that lie somewhere between the extremes. In these states, neither p nor x is precisely known, but the uncertainty of one is as small as it can be given the uncertainty of the other. These special states are often called “Gaussian wave packets”, and they are ideal for showing us how Heisenberg’s uncertainty principle plays out.

In Fig. 3 I’ve shown a wave function for a particle whose position is poorly known but whose momentum is better known. This wave function looks like a trimmed version of the |P0> state of Fig. 1, and indeed the momentum of the particle won’t be too far from P0. The position is clearly centered to the right of the vertical axis, but it has a large probability to be on the left side, too. So in this state, Δp is small and Δx is large.

Figure 3: A wave function similar to that of Fig. 1, describing a particle that has an almost definite momentum and a rather uncertain position.

In Fig. 4 I’ve shown a wave function of a wave packet that has the situation reversed: its position is well known and its momentum is not. It looks like a smeared out version of the |X0> state in Fig. 2, and so the particle is most likely located quite close to X0. We can see the wave function shows some wavelike behavior, however, indicating the particle’s momentum isn’t completely unknown; nevertheless, it differs greatly from the simple wave in Fig. 1, so the momentum is pretty uncertain. So here, Δx is small and Δp is large.

Figure 4: A wave function similar to that of Fig. 2, describing a particle that has an almost definite position and a highly uncertain momentum.

In this way we can interpolate however we like between Figs. 1 and 2, getting whatever uncertainty we want on momentum and position as long as they are consistent with Heisenberg’s uncertainty relation.

Wave functions in the space of possible momenta There’s even another more profound, but somewhat more technical, way to see the symmetry in action; click here if you are interested.

As I’ve emphasized recently (and less recently), the wave function of a system exists in the space of possibilities for that system. So far I’ve been expressing this particle’s wave function as a space of possibilities for the particle’s location — in other words, I’ve been writing it, and depicting it in Figs. 1 and 2, as Ψ(x). Doing so makes it more obvious what the probabilities are for where the particle might be located, but to understand what this function means for what the particle’s motion takes some reasoning.

But I could instead (thanks to the symmetry between position and momentum) write the wave function in the space of possibilities for the particle’s motion! In other words, I can take the state |P0>, in which the particle has definite momentum, and write it either as Ψ(x), shown in Fig. 1, or as Ψ(p), shown in Fig. 1a.

Figure 1a: The wave function of Fig. 1, written in the space of possibilities of momenta instead of the space of possibilities of position; i.e., the horizontal axis show the particle’s momentum p, not its position x as is the case in Figs. 1 and 2. This shows the particle’s momentum is definitely known. Compare this with Fig. 2, showing a different wave function in which the particle’s position is definitely known.

Remarkably, Fig. 1a looks just like Fig. 2 — except for one crucial thing. In Fig. 2, the horizontal axis is the particle’s position. In Fig. 1a, however, the horizontal axis is the particle’s momentum — and so while Fig. 2 shows a wave function for a particle with definite position, Fig. 1a shows a wave function for a particle with definite momentum, the same wave function as in Fig. 1.

We can similarly write the wave function of Fig. 2 in the space of possibilities for the particle’s position, and not surprisingly, the resulting Fig. 2a looks just like Fig. 1, except that its horizontal axis represents p, and so in this case we have no idea what the particle’s momentum is — neither the particle’s speed nor its direction.

Fig. 2a: As in Fig. 1a, the wave function in Fig. 2 written in terms of the particle’s momentum p.

The relationship between Fig. 1 and Fig. 1a is that each is the Fourier transform of the other [where the momentum is related to the inverse wavelength of the wave obtained in the transform.] Similarly, Figs. 2 and 2a are each other’s Fourier transforms.

In short, the wave function for the state |P0> (as a function of position) in Fig. 1 looks just like the wave function for the state |X0> (as a function of momentum) in Fig. 2a, and a similar relation holds for Figs. 2 and 1a. Everything is symmetric!

The Symmetry and the Particle…

So, what’s this all got to do with electrons and other elementary particles? Well, if a “particle” is really and truly a particle, an object of infinitesimal size, then we certainly ought to be able to put it, or at least imagine it, in a position state like |X0>, in which its position is clearly X0 with no uncertainty. Otherwise how could we ever even tell if its size is infinitesimal? (This is admittedly a bit glib, but the rough edges to this argument won’t matter in the end.)

That’s where this symmetry inherent in 1920s quantum physics comes in. We do in fact see states of near-definite momentum — of near-definite motion. We can create them pretty easily, for instance in narrow electron beams, where the electrons have been steered by electric and magnetic fields so they have very precisely defined momentum. Making position states is trickier, but it would seem they must exist, thanks to the symmetry of momentum and position.

But they don’t. And that’s thanks to a crucial asymmetry between location and motion that we’ll explore next time.

A rocky planet less than half the mass of Earth seems to have an atmosphere made almost entirely of sulphur dioxide – this could be due to a huge amount of volcanic activity

There are many theories about how dynamics in the early solar system led to the cosmic neighbourhood we now inhabit, but beyond computer simulations, direct evidence to support them is hard to come by – that's where meteorites come in

Clothes and fishing nets that are made of nylon often end up in landfill or dumped in oceans, but a new way to break down the plastic could improve recycling

Albert Einstein himself thought that the eponymous Einstein ring would be impossible to observe, but the Euclid telescope has picked one up just 600 million light years from Earth

Friday, the Trump administration slashed indirect costs associated with NIH grants. What does this mean, and why could it be so disastrous for biomedical research?

The post DOGE vs. the NIH: Say goodbye to the greatest engine of biomedical research ever created first appeared on Science-Based Medicine.

I wish I had a happier post for number 30,000, but you’re stuck with this one. However, it’s in line with the kind of stuff I’ve been writing about for a while, so it’s appropriate.

Today we must deal with a letter from the Presidents of three organismal evolution and ecology societies (The Society for the Study of Evolution, American Society of Naturalists, and the Society of Systematic Biologists), a Diktat declaring that biological sex is not binary, exactly as they did in 2018 (same societies, almost the same statement).  Both letters were also responses to statements by the U.S. government headed by Trump, taking issue with the government’s position that sex is binary. HHS incorrectly used genitalia as an earlier criterion for what was binary, but Trump’s new Executive Order uses an accurate definition of sex, one based on whether an individual’s reproductive apparatus is set up to produce large immobile or small mobile gametes. (I guess I should make the requisite disclaimer that while I agree with much but not all of Trump’s statement, that doesn’t mean I endorse Trump!)

My critique of the 2018 statement is posted at this site. I took the position that scientific societies shouldn’t take ideological stands unless they are attacking an ideology that damages the mission of the society itself, and are making a statement that corrects an incorrect but widespread view.  Well, this again applies here: these three societies are attacking a biological fact: the binary definition of biological sex, something well within the ambit of biology societies. The problem is that, as in 2018, the three societies are using misleading and false arguments to show that biological sex is a spectrum.  Further, as in 2018, the motivation for this statement does not appear to be a scientifically-based attempt to correct government misinformation, but rather seems to be ideological.  In fact, biologists have recognized sex as binary (with a few very rare exceptions) since the late nineteenth century, and have based the binary conclusion on the fact that all animals and plants produce two types of gametes, with no intermediates (see below for references).

The desperate attempt in this letter, and the one in 2018, to show that sex is a spectrum intends, I think, to buttress those people who either feel they don’t belong in one of the two sexes, are transsexual (a behavior that assumes two sexes) or feel that they are somewhere in between—or even members of neither sex. But the attempt is misguided, for, as I’ve said repeatedly, morality, as The Naturalistic Fallacy and The Appeal to Nature Fallacy argue, should not be strongly based on biological reality. Observing nature does not tell us what is right or wrong, or specify how we should behave towards others.

However, the 2018 and present letters, instantiate a third falacy—what Luana Maroja and I call the “reverse naturalistic fallacy” described in our Skeptical Inquirer paper (bolding is mine below):

Both fallacies lead to the same errors. First, if we condition our politics and ethics on what we know about nature, then our politics and ethics become malleable to changes in what we discover about nature later. For example, the observation that female bonobos rub each other’s genitals as a bonding behavior has been used to justify why human homosexuality is neither offensive nor immoral. Bonobo behavior is, after all, “natural.” (Similar same-sex behaviors have been reported in many species and have been used to the same end.) But what if no such behavior had been seen in any nonhuman species? Or what if the bonobo observation was shown to be wrong? Would this make homosexual behavior immoral or even criminal? Of course not, because enlightened views of homosexuality rest not on parallels with nature but on ethics, which tells us that there’s nothing immoral about consensual sex between adults.

Second, we must realize that many behaviors that are “natural” because they’re found in other species would be considered repugnant or immoral in our own. These include infanticide, robbery, and extra-pair copulation. As one of us wrote, “If the gay cause is somehow boosted by parallels from nature, then so are the causes of child-killers, thieves and adulterers.” But we don’t really derive our morality or ideology from nature. Instead, we pick and choose those behaviors in other species that happen to resemble a morality we already have. (People do exactly the same thing—ignoring the bad behaviors and lauding the good ones—when they pretend to derive morality from religious texts such as the Bible.)

All the biological misconceptions we’ve discussed involve forcing preconceived beliefs onto nature. This inverts an old fallacy into a new one, which we call the reverse appeal to nature. Instead of assuming that what is natural must be good, this fallacy holds that “what is good must be natural.” It demands that you must see the natural world through lenses prescribed by your ideology. If you are a gender activist, you must see more than two biological sexes. If you’re a strict egalitarian, all groups must be behaviorally identical and their ways of knowing equally valid. And if you’re an anti-hereditarian—a blank slater who sees genetic differences as promoting eugenics and racism—then you must find that genes can have only trivial and inconsequential effects on the behavior of groups and individuals. This kind of bias violates the most important rule of science, famously expressed by Richard Feynman: “The first principle is that you must not fool yourself—and you are the easiest person to fool.”

Thus the latest letter, like the earlier one, is apparently written to try to convince people that in reality sex is not binary in nature, thereby buttressing gender-activist ideology.  It is not meant to clarify mistaken biological views. In fact, the letters muddy the waters by presenting a misguided view of sex and giving it the imprimatur of biological societies. As we’ve learned so often recently, though, what scientific societies and journals say often flouts the truth, intended to be ideological rather than scientific.

The problem, then, is not that the societies are making a political statement about biology. The problem is twofold. First, the societies’ attempt to buttress their biological argument is wrong, involving a lot of misleading assertions—all in three short paragraphs.

Second, the Presidents of the Society say they are speaking not only for the 3500 scientists who belong to their organizations, but also for the majority of biologists, saying that their conception of sex represents a scientific “consensus”.   It does not, nor do they know this. They did not poll their members before issuing their statement, and they buttress their argument by citing just two papers, one a very short Scientific American op-ed showing that the development of biological sex is complex and can be derailed by a number of mutations, the other a Nature paper by a freelance science journalist who uses a similar argument: the process of sex determination is “complex.” Indeed it is, but development is always complex, and yet, remarkably, evolution has channeled it into two pathways with similar destinations in all animals and vascular plants, producing, by a variety of developmental processes, two types of individuals in these species, one producing sperm and the other eggs. And that journalist, as you see below, doesn’t support the statement at all! Did they even bother to check that? (h/t: a reader below):

No, not at all. Two sexes, with a continuum of variation in anatomy/physiology.

— Claire Ainsworth (@ClaireAinsworth) July 21, 2017

The best refutation of the letter below is actually Richard Dawkins’s Substack piece on the binary nature of sex (excerpted from a forthcoming essay), “Is the male female divide a social construct or a scientific reality?” I recommend that you read it after you read the letter below. But I’ll give one quote from the piece first, showing Dawkins presenting the “Universal Biological Definition” (UBD) of sex:

It is no idle whim, no mere personal preference, that leads biologists to define the sexes by the UBD. It is rooted deep in evolutionary history. The instability of isogamy [the condition in which all individuals have gametes of the same size], leading to extreme anisogamy [the condition in which individuals have gametes of different sizes, meaning two], is what brought males and females into the world in the first place. Anisogamy has dominated reproduction, mating systems, social systems, for probably two billion years. All other ways to define the sexes fall afoul of numerous exceptions. Sex chromosomes come and go through evolutionary time. Profligate gamete-spewing into the sea gives over to paired-off copulation and vice versa. Sex organs grow and shrink and grow again as the aeons go by, or as we jump from phylum to phylum across the animal kingdom. Sometimes one sex exclusively cares for the young, seldom the other, often both, often neither. Harem systems change places with faithful monogamy or rampant promiscuity. Psychological concomitants of sexuality change like the wind. Amid a rainbow of sexual habits, parental practices, and role reversals, the one thing that remains steadfastly constant is anisogamy. One sex produces gametes that are much smaller, and much more numerous, than the other. That is all ye know of sex differences and all ye need to know, as Keats might have only slightly exaggerated if he’d been an evolutionary biologist.

On to the letter, and I’ll try to be brief since Richard’s piece shows the fallacies inherent in their defense of a “spectrum” of biological sexes. The letter is indented, and you can see the original by clicking the title below:

Policy: Letter to the US President and Congress on the Scientific Understanding of Sex and Gender

Contributed by kjm34 on Feb 06, 2025 – 11:35 PM

President Donald J Trump
Washington, DC

Members of the US Congress
Washington, DC

February 5, 2025

RE: Scientific Understanding of Sex and Gender

Dear President Trump and Members of the US Congress,

As scientists, we write to express our concerns about the Executive Order “Defending Women From Gender Ideology Extremism And Restoring Biological Truth To The Federal Government”. That Order states first, that “there are two sexes…[which] are not changeable”. The Order goes on to state that sex is determined at conception and is based on the size of the gamete that the resulting individual will produce. These statements are contradicted by extensive scientific evidence.

Scientific consensus defines sex in humans as a biological construct that relies on a combination of chromosomes, hormonal balances, and the resulting expression of gonads, external genitalia and secondary sex characteristics. There is variation in all these biological attributes that make up sex. Accordingly, sex (and gendered expression) is not a binary trait. While some aspects of sex are bimodal, variation along the continuum of male to female is well documented in humans through hundreds of scientific articles. Such variation is observed at both the genetic level and at the individual level (including hormone levels, secondary sexual characteristics, as well as genital morphology). Beyond the incorrect claim that science backs up a simple binary definition of sex, the lived experience of people clearly demonstrates that the genetic composition at conception does not define one’s identity. Rather, sex and gender result from the interplay of genetics and environment. Such diversity is a hallmark of biological species, including humans.

We note that you state that “Basing Federal policy on truth is critical to scientific inquiry, public safety, morale and trust in the government itself”. We agree with this statement. However, the claim that the definition of sex and the exclusion of gender identity is based on the best available science is false. Our three scientific societies represent over 3500 scientists, many of whom are experts on the variability that is found in sexual expression throughout the plant and animal kingdoms. More information explaining why sex lies along a continuum can be found here, under the Education and Outreach tab. If you wish to speak to one of our scientists, please contact any of the societies listed below.

Carol Boggs, PhD
President
Society for the Study of Evolution
president@evolutionsociety.org

Daniel Bolnick, PhD
President
American Society of Naturalists

Jessica Ware, PhD
President
Society of Systematic Biologists
president@systematicbiologists.org

Oh dear; what a thicket of misguided argumentation we must make our way through here! Let’s take it paragraph by paragraph.

The first paragraph simply denies that there are two sexes, with sex is defined by gamete size. These contentions, they say are contradicted by “extensive scientific evidence”.  But they cite only two papers supporting that, throwing out a number of traits connected with sex but not part of the UBD, a definition that goes at least as far back back as Robert Payne Bigelow in 1894. For a list of gamete-based definitions from different eras, see this paper by Carlos Y. Fuentes (pdf here); the article is in Spanish but should self-translate into English.  To check a more recent book, I just pulled the second edition of Doug Futuyma’s textbook Evolution on my shelf, whose various editions I taught from at Chicago. Sure enough, on p. 389 I find this:

Most sexually reproducing species have distinct male or female sexes, which are defined by a difference in the size of their gametes (ANISOGAMY). In ISOGAMOUS organisms, such as Chlamydomonas and many other algae, the uniting cells are the same size; such species have mating types but not distinct sexes.

I’ve pointed out before that the sex binary applies to all animals (including of course us) and all vascular plants, but not to protists, algae, and some fungi.  But the UBD of course centers on humans, not algae or fungi, for humans are the object of the letter below. (They do note that the trait diversity that produces a sex spectrum applies to all biological species!)

The second paragraph can be addressed by Dawkins’s excerpt above: it mentions a lot of traits associated with biological sex that show variation, but these are not part of the UBD itself.  Let me repeat his words again:

All other ways to define the sexes fall afoul of numerous exceptions. Sex chromosomes come and go through evolutionary time. Profligate gamete-spewing into the sea gives over to paired-off copulation and vice versa. Sex organs grow and shrink and grow again as the aeons go by, or as we jump from phylum to phylum across the animal kingdom. Sometimes one sex exclusively cares for the young, seldom the other, often both, often neither. Harem systems change places with faithful monogamy or rampant promiscuity. Psychological concomitants of sexuality change like the wind. Amid a rainbow of sexual habits, parental practices, and role reversals, the one thing that remains steadfastly constant is anisogamy. One sex produces gametes that are much smaller, and much more numerous, than the other. That is all ye know of sex differences and all ye need to know, as Keats might have only slightly exaggerated if he’d been an evolutionary biologist.

And of course we do see variation in sex organs, chromosomes, behavior, and so on, as well as “the lived experience of people”, which has nothing to do with any biological definition of sex. (What is the “lived experience” of sea urchins, foxes, or gingko trees, that would affect the binary nature of sex in those species?) In humans, the frequency of exceptions to the sex binary lies between 1/5600 individuals and 1/20,000 individuals. As I’ve said, that’s as close to a binary as you can get.

The authors also say this:

Scientific consensus defines sex in humans as a biological construct that relies on a combination of chromosomes, hormonal balances, and the resulting expression of gonads, external genitalia and secondary sex characteristics. There is variation in all these biological attributes that make up sex.

I have no idea what a “biological construct” is! What is the consensus about the meaning of that term?

The argument proceeds to cite a number of factors associated with sex in some but not all species, but, as Dawkins notes, these traits do not partake in the UBD noted by biologists well before we learned about chromosomes or hormones.

The authors fail to address this important question: if sex is defined by where an organism is positioned along dozens of variable axes, like hormone titer, lived experience, external genitalia, sex chromosomes (many species don’t have these), and other secondary sex traits (there’s a reason they’re called “secondary”!), then how do we determine what sex an individual is? It would have to be some kind of combinatorial, multifactoral analysis that takes all these factors into account. And of course it would result in the delineation of a gazillion sexes within many species—perhaps an infinite number in humans! Is that what the authors really believe.  If they say they are “male,” for example, how do they know that?

And yet I’m sure that all of the authors of this letter, if they work on animals or plants, would use the terms “male” and “female” without defining them.  For example, ASN President Daniel Bolnick, who works on stickleback fish, also sells them from his lab’s “stickleback stock center”. Below are the going prices. Note that they sell ony two sexes of stickleback: male and female. Why aren’t there more? Aren’t there sticklebacks with a lived experience that aren’t either male or female? How does Bolnick define these sexes and why aren’t there more of them?

I see this is running long, so I’ll make just two more points.

First, the spectrum of sex and the denial of the UBD is said not just to apply to humans, but to all species!  From paragraph two of the letter (my bolding):

Beyond the incorrect claim that science backs up a simple binary definition of sex, the lived experience of people clearly demonstrates that the genetic composition at conception does not define one’s identity. Rather, sex and gender result from the interplay of genetics and environment. Such diversity is a hallmark of biological species, including humans.

What?  All biological species have the kind of diversity that effaces the sex binary, so they must not participate in the UBD, either?  Did the authors realize what they were saying? Is sex a spectrum in elephants, possums, aardvarks, cougars, and so on?

Finally, note that the paper repeatedly emphasizes the authority of their societies, as if they were speaking for all their members. But their members were not polled on this (I’ve asked some), and so the statements must have come from the Presidents themselves or more likely the small board of officers of the societies.  It is a Diktat from on high, and the implied unanimity is false. Some members I’ve talked to in the last few days absolutely disagree with the statement and are even offended that they are implicitly characterized as agreeing that sex is non-binary.  Nor do several people I’ve talked to observed a “scientific consensus” that sex is somehow defined by combining a number of traits in a multifactoral way.

The statement below should and will offend the many members of these societies who do see sex as binary:

However, the claim that the definition of sex and the exclusion of gender identity is based on the best available science is false. Our three scientific societies represent over 3500 scientists, many of whom are experts on the variability that is found in sexual expression throughout the plant and animal kingdoms. More information explaining why sex lies along a continuum can be found here, under the Education and Outreach tab. If you wish to speak to one of our scientists, please contact any of the societies listed below.

Well, I could produce a long list of members of these three societies who do not endorse the letter above. (I was once President of the SSE and don’t endorse it, and I have considerable expertise examining the variability of sex expression in fruit flies. In the comments section below you’ll find another former SSE President who disagrees with their new letter as well.)

In the end, what we see here is three prominent organismal-biology societies having been ideologically captured to the point where they will twist and misrepresent scientific fact to buttress an ideologically-based view that sex is a spectrum.  These societies and their Presidents should be ashamed of themselves.  Scientific truth is not determined by pronouncements of the presidents of scientific societies, however notable these presidents may be.  The UBD is one of the great (and few) generalizations in evolutionary biology, a definition that’s been immensely fruitful in understanding things like sexual selection. It’s a great pity that these societies are trying to scupper the UBD simply to buttress an evanescent form of gender ideology.

As expected, the Musk/Trump administration has aimed its guns at the US university system, deciding that universities that get grants from the federal government’s National Institute of Health will have their “overhead” capped at 15%. Overhead is the money that is used to pay for the unsung things that make scientific research at universities and medical schools possible. It pays for staff that keep the university running — administrators and accountants in business offices, machinists who help build experiments, janitorial staff, and so on — as well as the costs for things like building maintenance and development, laboratory support, electricity and heating, computing clusters, and the like.

I have no doubt that the National Science Foundation, NASA, and other scientific funding agencies will soon follow suit.

As special government employee Elon Musk wrote on X this weekend, “Can you believe that universities with tens of billions in endowments were siphoning off 60% of research award money for ‘overhead’? What a ripoff!”

The actual number is 38%. Overhead of 60% is measured against the research part of the award, not the total award, and so the calculation is 60%/(100%+60%) = 37.5%, not 60%/100%=60%. This math error is a little worrying, since the entire national budget is under Musk’s personal control. And never mind that a good chunk of that money often comes back to research indirectly, or that “siphon”, a loaded word implying deceit, is inappropriate — the overhead rate for each university isn’t a secret.

Is overhead at some universities too high? A lot of scientific researchers feel that it is. One could reasonably require a significant but gradual reduction of the overhead rate over several years, which would cause limited damage to the nation’s research program. But dropping the rate to 15%, and doing so over a weekend, will simply crush budgets at every major academic research institution in the country, leaving every single one with a significant deficit. Here is one estimate of the impact on some of the United States leading universities; I can’t quickly verify these details myself, but the numbers look to be at the right scale. They are small by Musk standards, but they come to something very roughly like $10000, more or less, per student, per year.

Also, once the overhead rate is too low, having faculty doing scientific research actually costs a university money. Every new grant won by a scientist at the university makes the school’s budget deficit worse. Once that line is crossed, a university may have to limit research… possibly telling some fraction of its professors not to apply for grants and to stop doing research.

It is very sad that Mr. Musk considers the world’s finest medical/scientific research program, many decades in the making and of such enormous value to the nation, to be deserving of this level of disruption. While is difficult to ruin our world-leading medical and scientific research powerhouse overnight, this decision (along with the funding freeze/not-freeze/kinda-freeze from two weeks ago) is a good start. Even if this cut is partially reversed, the consequences on health care and medicine in this country, and on science and engineering more widely, will be significant and long-lasting — because if you were one of the world’s best young medical or scientific researchers, someone who easily could get a job in any country around the globe, would you want to work in the US right now? The threat of irrational chaos that could upend your career at any moment is hardly appealing.

It’s Sunday, and that means John Avise Photograph Day. John continues today with his series on North American butterflies. His IDs and captions are indented, and you can enlarge his photos by clicking on them. This is post 29,999

Butterflies in North America, Part 9 

This week continues my multi-part series on butterflies that I’ve photographed in North America.  I’m continuing to go down my list of species in alphabetical order by common name.  With this post, we’ve reached the halfway point of my photographic tour through this continent’s many Lepidopterans.

Juba Skipper (Hesperia juba), topwing:

Juba Skipper, underwing:

Julia Heliconian (Dryas iulia), upperwing:

Leonard’s Skipper (Hesperia leonardus), male:

Leonard’s Skipper, female:

Little Glassywing (Vernia verna), underwing:

Little Wood Satyr (Megisto cymela), underwing:

Long Dash Skippper (Limochores mystic):

Long-tailed Skipper (Urbanus proteus), topwing:

Long-tailed Skipper, underwing:

Lorquin’s Admiral (Limenitis lorquini), topwing:

Lorquin’s Admiral, underwing:

On October 14th, 2024, NASA’s Europa Clipper mission launched atop a Falcon Heavy rocket from Launch Complex 39A at the Kennedy Space Center in Florida. It will spend the next few years traveling 2.9 billion km (1.8 billion mi) to reach Jupiter’s moon Europa, arriving in April 2030. Once it arrives in the system, the probe will establish orbit and conduct 49 close flybys of this “Ocean World” and search for chemical elements that could indicate the presence of life (biosignatures) in the moon’s interior. By July 2031, it will be joined by the ESA’s Jupiter Icy Moon Explorer (JUICE), which will conduct a similar search around Callisto and Ganymede.

As is customary, the mission team has been checking and calibrating the Clipper’s instruments since launch to ensure everything is in working order. The latest test involved the probe’s stellar reference units (or star trackers), which captured and transmitted the Europa Clipper’s first images of space. These two imaging cameras look for stars, which mission controllers use to help orient the spacecraft. This is critical when pointing the probe’s telecommunications antennas toward Earth so it can send and receive critical mission data.

The picture (shown below) is composed of three shots that show stars 150 to 300 light-years away. The starfield includes the four brightest stars of the constellation Corvus (Gienah, Algorab, Kraz, and Alchiba), the Latin word for crow—a bird in Greek mythology associated with Apollo. The starfield represents about 0.1% of the sky around the spacecraft, but this is enough for other spacecraft to determine its orientation. A 3D model of NASA’s Europa Clipper can be viewed in the agency’s interactive Eyes on the Solar System.

Contrary to what you might expect, orientation is a separate process from navigation and is critical to telecommunications and science operations. Whereas navigation is all about making sure the mission is headed in the right direction (by first determining where it is in space), orientation involves using star trackers to determine where the science instruments are pointed. This includes the Europa Imaging System (EIS), which will help scientists map the moon’s surface and its many mysterious features – the fractures, ridges, and valleys caused by resurfacing events.

The checkout phase has been happening ever since Europa Clipper launched in October, and these photos show that the latest instrument check was successful. Joanie Noonan of NASA’s Jet Propulsion Laboratory leads the mission’s guidance, navigation, and control operations. “The star trackers are engineering hardware and are always taking images, which are processed on board,” she said in a NASA press release. “We usually don’t downlink photos from the trackers, but we did in this case because it’s a really good way to make sure the hardware — including the cameras and their lenses — made it safely through launch.”

When the Europa Clipper reaches its destination, it will conduct 49 flybys of the moon and gather information using its nine science instruments. In addition to the EIS, the probe will rely on the Europa Thermal Emission Imaging System (E-THEMIS) to detect warmer regions that could be liquid water near the surface or plume activity. It will also carry two spectrometers – which measure light in the ultraviolet (UV) and infrared (IR) wavelengths – to determine the composition of Europa’s surface and atmospheric gases and measure the distribution of ices, salts, organics, and the warmest hotspots on Europa.

Other instruments include magnetometers that will measure Europa’s induced magnetic field, confirm the existence of its internal ocean, and determine its depth. There are also gravity and radar instruments that will measure the moon’s gravitational field and probe beneath the icy surface, a dust spectrometer and neutral gas mass spectrometer to identify the materials Europa ejects or vents into space, and a spectrometer to study the chemistry of the moon’s atmosphere and plumes and its subsurface ocean.

Could shallow lakes be locked away in Europa’s crust? Europa Clipper will find out. Credit: NASA

This advanced suite of instruments will help the Europa Clipper mission accomplish its three main science objectives: to determine the thickness of the moon’s icy shell, to investigate its composition, and to characterize its geology. In so doing, it will confirm (or deny) that Europa and its internal ocean have the necessary ingredients and conditions to support life. The mission’s detailed exploration will inform scientists about the conditions of other “Ocean Worlds” in the Solar System (and beyond) and their potential for habitability.

If the mission is successful and the Europa Clipper potential biosignatures, NASA may follow up with the proposed Europa Lander. This mission, if realized, will set down on Europa’s icy surface and study its composition and plume activity directly, the results of which could definitively prove the existence of extraterrestrial life. The Europa Clipper is currently 85 million km (53 million mi) from Earth and is traveling at a speed of 27 km per second (17 mps). The craft is rapidly approaching Mars, and on March 1st, engineers will steer the probe to take advantage of a gravity assist with the Red Planet.

Further Reading: NASA

The post Europa Clipper Tests its Star Tracker Navigation System appeared first on Universe Today.

The first of our three items today (plus there’s lagniappe at the bottom) are the three best cat commercials ever made.  I chose the first two, but reader Divy insisted that I add the third,

This one was originally broadcast on the Superbowl, and in my view has never been bettered for a cat commercial. Repeated watching enables you to pick up things you missed the first time.  It even has its own Wikipedia entry, “Cat herders“, which says, among other stuff, this:

Cat Herders is a commercial made by Fallon for Electronic Data Systems (EDS). Alluding to the management-speak idiom “It’s like herding cats” that refers to the impossibility of controlling the uncontrollable, it posits an analogy between herding cats and the solution of seemingly impossible problems by EDS.

. . . Authentic cowboys were required, and a casting call was put out across Arizona, New Mexico, Colorado and California. Some of the cast had never acted previously but others were SAG-accredited.

Actor Tony Becker points out that many of the actors were “real-life cowboys”, and gives a comprehensive cast list [the list is on the page]

Real cowboys!

Here’s a well-known Cravendale Milk ad for cats with thumbs. Very clever!

And here’s one of the “got milk?” series that is Divy’s favorite. Cats don’t have no truck with fake milk!

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This is from Fox News, but there’s no politics in it—just humanity. Click to read about a lovely man who rescued a kitten from a bunch of horrible people who glued it to a road! How much more disgusting can people get?

An excerpt (the story is from October of 1918):

A tiny kitten may have shaved off one of his nine lives after being discovered glued to a busy road in Oregon on Friday.

Chuck Hawley was driving to work on Silverton Road Northeast just outside of Salem around 7 a.m. when he noticed there was something in the road in a busy lane of traffic.

“When I went to pick her up, her feet were stuck to the road, and I’m like, ‘uh oh.’ So I start to pull her feet up, and it was like a rubber cement, so she was glued to the road.” Hawley told FOX12. “It was all under her neck and then she had a little bit down her side, but it was mostly her tail and her feet.”

The 5-week-old kitten, frightened and cold, had her feet soaked in glue that was “sort of rubbed into the pads of her feet,” according to Hawley.

“Sticky” the kitten was found with her feet stuck to a busy road on Friday. (FOX12)

“I think the way she was sitting someone actually went out and put her there,” he told FOX12. “Because there were no glue footprints around, it was just a glob of glue under her, so it looked like someone just took her and put her in the road.”

Hawley took the kitten, now named Sticky, to an animal clinic where staff members had to use mineral oil to get the glue off her tiny paws. Puncture wounds were also found on the kitten’s neck, but it’s yet to be determined what caused them.

On Monday, Hawley said he spoke with deputies from the Marion County Sheriff’s Office, who came to his home to take pictures of Sticky’s neck injuries as they investigate how she ended up glued to the road.

And so Sticky was saved!

The little kitten is expected to make a full recovery — and wound up getting a new home out of the ordeal after Hawley adopted her.

“The funny thing is we were just talking about getting a cat a couple of nights ago,” he said. “Seems like there’s easier ways for the cat to find us, but if that’s how we’re doing it, okay, I guess that’s how we’ll do it.”

Here’s a 2-minute4 video:

Stuff like this both restores my faith in humanity but also makes me realize how horrible some people are. Torturing a poor animal that never did anything to you! Isn’t that the way that some serial killers start?

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From Bored Panda we have some vintage cat photos. The site has twenty, but I’ll show half a dozen.  Click on the headline below to see them.

First, BP‘s intro:

Cats have a way of capturing our attention and our hearts, and it’s not just a modern thing. Long before the internet, people were photographing their furry companions, preserving those moments for generations to enjoy. Thanks to Paula Leite Moreira, a Brazilian journalist and the creator of the Instagram account “All Vintage Cats,” these charming snapshots from the past are now reaching a whole new audience.

Paula’s collection is like a time machine for cat lovers. From historical archives to forgotten magazines, she’s unearthed photos that show cats in all their timeless glory—lounging, playing, or even posing with famous faces. If you’re someone who appreciates old photographs or just loves cats, this project is a quiet little gold mine you won’t want to miss. Scroll down to take a look at some of the gems she’s shared.

Milk right from the source!  A note from the article:

Bored Panda reached out to Paula Leite Moreira once more to learn more about her insights on the evolving portrayal of cats in photography across different eras and cultures.

When asked if she noticed any patterns or trends in how cats were photographed across different decades or countries, the journalist mentioned that in the early days of photography, around the mid-19th century in Europe, photos often depicted kittens mimicking human poses, sometimes even dressed in tiny outfits. “These images were frequently made for postcards. But aside from that period, it’s remarkable how photos from decades ago are similar to those we see today. Owners also enjoyed capturing casual moments with their cats at home, with their families, in an unpretentious way.”

From the article:

We were curious about the most surprising or unusual place where Paula came across a vintage photo of a cat. “Definitely a photo of a kitten ‘hidden’ in the so-called ‘longest beard in the world’ of a Frenchman named Louis Coulo,” the journalist responded.

It is a great photo, and here it is:

View this post on Instagram

A post shared by All Vintage Cats (@allvintagecats)

 

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Lagniappe: From Newsweek, a cat with salacious markings (below).  I don’t think the black bit looks like a middle finger, though:

Picking a name for a pet is no easy task, which is why one owner took to Reddit and asked for name suggestions, but the answers they received were unexpected.

Reddit user u/martindukz posted to the subreddit channel r/funny a picture of the unnamed brown, white and black calico cat sitting on a footrest. Within four days, the post received over 27,000 upvotes and almost 10,000 comments.

People were basing their suggestions on a specific physical characteristic. The shape of the black fur marking on her lower back immediately gave people ideas; however, the suggestions weren’t what the owner expected. People flooded the comment section with not-safe-for-work name options.

The owner commented on the post, saying the cat’s name is Chili, but based on the marking, they are open to renaming her; hence, the post to Reddit.

Newsweek reached out to u/martindukz via Reddit for additional comment.

“I may be a little dark, but I see a middle finger in that black splotch. I won’t make any name suggestions,” commented one Reddit user.

Others suggested subtle names after humans such as Richard or the author Charles Dickens. A more subtle name idea was Clickbait “because that mark looks like a computer mouse.”

Not everyone had their heads in the gutter. Someone asked: “Am I the only one that thinks it’s a lighthouse?”

h/t: Dan, Divy

Today we have photos of amphibians and other items from Matt Moran, an ecologist at Monteverde in Costa Rica as well as Professor Emeritus in the Department of Biology and Health Sciences at Hendrix College, Conway, Arkansas.  Matt’s captions are indented, and you can enlarge his photos by clicking on them.

These are photos from the Children’s Eternal Rainforest in Costa Rica (25,000 hectares), where I work as a field biologist. I am engaged in several projects, but my major one is a study on the status of amphibians in the park. Amphibians around the world have been declining and this area of Costa Rica is one of first places it was documented. While many theories have been developed as to why amphibians are declining, the one with the most support that explains the sometimes sudden collapse of amphibian populations (especially frogs) is the arrival of a pathogenic fungus (Batrachochytrium dendrobatidis), commonly called chytrid. This fungus infects the skin of frogs and often causes high levels of mortality. It has been implicated in the extinction of dozens of species of frogs around the world.

In the Monteverde area where I work, the population collapses occurred in the late 1980s. Initially, 25 of the known 50 species from the area were missing, but over time, most reappeared, apparently surviving in small numbers and then recolonizing larger areas. It appears that this was a major selection event, so that individuals with natural resistance to the fungus survived to reproduce, while most died. It is estimated that in many species, over 99% of individuals died. About 5 species originally found in the area appear to be totally extinct. Others still missing from here exist elsewhere, although often at critically low levels. Many, however, have recovered and probably exist at levels similar to pre-fungus invasion times.

I am attempting to determine the frog community structure 35 years post-chytrid invasion. These data will be valuable in two ways: 1) to determine how the community structure has changed over the last 35 years, and 2) to determine how future community structure is different from today so that we will have long-term population trends (using now as a baseline).

This is an amazing place to work. I retired from academia several years ago and this has become my new passion. It is one of the most biodiverse protected areas on the planet and every minute I spend in the forest is enchanting beyond description.

Emerald Glass Frog (Espadarana prosoplebon). This is the most common glass frog (Family Centrolenidae) found in this area. As their name suggests, they have transparent skin on the ventral side and their internal organs are easily visible. Interestingly, this species, like most glass frogs, does not appear to have declined because of chytrid fungus invasion. Like all glass frogs, this one breeds in streams:

Reticulated Glass Frog (Hyalinobatrachium valerioi). A fairly common species in mid-elevation areas of rainforest. It is easily identified by the large yellow spots on the dorsal side:

Clay-colored Rain Frog (Pristimantis cerasinus). A small frog found perched on leaves in the rainforest. It is identified by its eye color, often called “sunset” eyes, with the contrasting yellow (dorsal) and brown (ventral) parts of the iris. It has direct development where eggs are laid on the forest floor and the tadpole develops inside the egg directly into a miniature version of the adult. This species declined with the arrival of chytrid fungus but now appears to be relatively common again:

Sunset over the Children’s Eternal Rainforest, Costa Rica:

Evergreen toad (Incilius coniferus). A common toad found in mid- and low-elevation rainforest. This species is one of the few true toads (Family: Bufonidae) that can readily climb vegetation, although they are also often found inside the burrows of other animals. They are highly toxic and probably have few predators:

Puma (Puma concolor) track. These big cats are common in rainforests through Costa Rica. We also have jaguars (Panthera onca), but jaguar tracks are the size of your hand, including the fingers!!, while puma tracks are the size of the palm of your hand. Because it had rained very hard the night before, I knew this track was less than 8 hours old!:

Atlantic Forest Toad (Incilius melanochlorus). Another common toad. This one declined dramatically with the arrival of chytrid fungus but now appears to have fully recovered:

A giant Ceiba tree (Ceiba pentandra). This is one of largest trees in Central America, reaching heights of over 70 meters. Because they often grown above the canopy (emergent tree), they are the favorite nesting sites of many raptors (e.g., Harpy Eagle, Harpia harpyja) where the elevated platform provides a good viewing point and relative safety from nest predators. This tree may be over 300 years old:

When I first saw this snake, I thought it was the highly venomous Fer-de-lance (Terciopelo in Costa Rican Spanish, Bothrops asper). However, this is the False Fer-de-lance (Xenodon rabdocephalus), a harmless mimic. I have often wondered if it is true case of mimicry trying to make potential predators think it is the deadly pit-viper or if its patten is actually an example of convergent evolution for camouflage. It might function in both ways in that it does provide great camouflage, but if spotted, it also has the pattern of something very dangerous!?:

JAC: I added a photo of a real fer-de-lance from Wikipedia:

thibaudaronson, CC BY-SA 4.0, via Wikimedia Commons

Our Moon continues to surprise us with amazing features. Scientists recently shared new information about two canyons that branch out from a major lunar impact. The site is the Schrödinger basin near the Moon’s South Pole. It formed when an asteroid or possibly even a leftover planetesimal slammed into the surface. It took only minutes to dig out that huge crater and split the landscape to make two huge rifts that extend from the site.

According to David Kring of the Lunar and Planetary Institute in Houston, TX, the impact is of very ancient origin. “Nearly four billion years ago,” he said, “an asteroid or comet flew over the lunar south pole, brushed by the mountain summits of Malapert and Mouton, and hit the lunar surface. The impact ejected high-energy streams of rock that carved two canyons that rival the size of Earth’s Grand Canyon. While the Grand Canyon took millions of years to form, the two grand canyons on the Moon were carved in less than 10 minutes.”

Those two canyons—named Vallis Schrödinger and Vallis Planck—are significant clues to that turbulent time in the Moon’s past. And, they’re impressive. Vallis Schrödinger is just under 300 kilometers long, 20 km wide, and 2.7 kilometers deep. Vallis Planck has two units. One is a deep canyon within the ejecta blanket of debris thrown out by the impact. The rest comprises a row of craters made as falling rocks were thrown out from the impact. They fell back to the Moon to create so-called “secondary craters.” The canyon part is about 280 kilometers deep, 27 km wide, and 3.5 km deep. The depth of both of these canyons surpasses the deep gorges of Earth’s Grand Canyon in Arizona.

Anatomy of an Impact and its Aftermath

The impactor probably slammed into the surface at nearly 55,000 kilometers per hour. The crash is what produced the enormous 320-kilometer-diameter Schrödinger impact basin. In the aftermath, the rocky debris scoured the deep canyons.

Schrödinger formed in the outer margin of the South Pole-Aitken (SPA) basin. At a diameter of about 2,400 km, it’s the largest and oldest impact basin on the Moon. The basin’s rim is about 300 km from the South Pole and within 125 km of the proposed exploration site for the Artemis mission.

The Schrödinger crater has a ~150-km diameter peak ring and the whole area is surrounded by a blanket of impact ejecta that splashed out in an irregular pattern up to 500 km away. The outermost crater ring resembles a circular mountain range and rises 1 to 2.5 km above the basin floor. It was produced by the collapse of a central uplift after the impact. After the impact, basaltic lava flows flooded the area. A large pyroclastic vent erupted more material onto the basin floor. That volcanic activity ended around 3.7 billion years ago.

Impact Anomalies

A careful analysis of the impact basin the canyons, and the ejecta surrounding the site by Kring and a team of scientists at the Lunar Planetary Laboratory, gives an idea of impact details. In a paper released about the site, the scientists discuss its features, plus some unusual finds. For example, the canyon rays don’t converge at the basin’s center as you might expect from typical impacts. They seem to come together in a different spot. That implies a point explosion impact.

Schrödinger peak-ring impact basin and two radiating canyons carved by impact ejecta. NASA\SVS\Ernest T. Wright. b Azimuthal Equidistant Projection of the Moon LRO LROC WAC Global Morphology Mosaic 100 centered on the Schrödinger basin, with the continuous ejecta blanket outlined and radial secondary crater rays (red). Vallis Schrödinger and Vallis Planck intersect near the southern rim of the basin (white point). The size of the point indicates the uncertainty. The projected bearing of the primary impactor (yellow) runs through the point of intersection and the basin center. A third unnamed feature extends in an uprange direction.

The location of the converging rays suggests that the incoming asteroid’s trajectory was about 33.5 west of north. The evidence also points to a distributed impact. That could mean the impactor came in at a low angle. Or, it’s also possible that secondary ejecta from the impact also came in at low angles. There are many secondary craters in the area which help explain the possibilities. Continued analysis will help explain the huge amounts of energy released in the event. Gareth Collins, one of Kring’s team members, said, “The Schrödinger crater is similar in many regards to the dino-killing Chicxulub crater on Earth. By showing how Schrödinger’s km-deep canyons formed, this work has helped to illuminate how energetic the ejecta from these impacts can be.”

Future Exploration

Of course, these rays and the impact basin will end up as great exploration points for NASA’s upcoming Artemis missions. Right now, the evidence from the ejecta blanket points to the fact that there’s an uneven distribution, particularly in the area where the first missions are planned. That will allow astronauts and robotic probes to reach underlying samples of the Moon’s primordial crust without having to dig through rocks of a younger age.

Since the basin is the second-youngest basin on the Moon, the impact melted rocks will be a great way to test the actual age of the impact. The general understanding is that some 3.8 billion years ago, the Moon (and Earth) experienced a great many of these collisions. This epoch was the Late Heavy Bombardment, thought to have lasted up to 200 million years. The continual impacts during this time scarred the surfaces of the rocky planets and the Moon, as well as asteroids. Lunar rocks created as a result of lava flows at that time will open a window into their ages and mineralogy, especially compared to other, older rock formations. They should also improve our understanding of that period of solar system history. In particular, it can help scientists characterize the impacts on Earth that affected not just the surface, but its life forms.

For More Information

Grand Canyons on the Moon (journal article)
Grand Canyons on the Moon

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How would detecting methane help astronomers identify if exoplanets, or even exomoons, have life as we know it, or even as we don’t know it? This is what a recent study published in The Astronomical Journal hopes to address as a team of researchers led by the NASA Goddard Space Flight Center investigated how a method called BARBIE (Bayesian Analysis for Remote Biosignature Identification on exoEarths) could be used on a future space mission to detect methane (CH4) on Earth-like exoplanets in optical (visible) and near-infrared (NIR) wavelengths. This study builds on past studies using BARBIE, known as BARBIE 1 and BARBIE 2, and has the potential to help scientists and engineers develop new methods for finding life beyond Earth and throughout the cosmos.

Here, Universe Today discusses this incredible study with Natasha Latouf, who is a PhD Candidate in the Department of Physics and Astronomy at George Mason University and lead author of the study, regarding the motivation behind the study, significant results, potential follow-up studies, next steps for BARBIE, the significance of detecting methane on Earth-like exoplanets, and if Natasha thinks we’ll ever find life on Earth-like exoplanets. Therefore, what was the motivation behind the study?

Latouf tells Universe Today, “We developed the BARBIE methodology in order to quickly investigate large amounts of parameter space and make informed decisions about the resultant observational trade-offs. Methane is a key contextual biosignature that we would be very interested in detecting, especially with other biosignatures like O2.”

As its name states, BARBIE used what’s known as a Bayesian inference, which is a statistical method employed to determine data probability outcomes based on a given input of data, meaning the probabilities change based on additional data input. As noted, this work builds off previous studies involving BARBIE, with those investigating parameters including observing exoplanets in optical wavelengths with planetary parameters including surface pressure, surface albedo, gravity, along with water (H20), oxygen (O2), and ozone (O3) abundance. However, those results indicated that only oxygen-rich atmospheres were observable in optical wavelengths, with the authors noting the parameters were too limited. With this work, known as BARBIE 3, the team added NIR wavelengths and CH4 to the parameters to broaden the parameters for more desirable results. Therefore, what were the most significant results from this study?

“The most significant results from this study is the interesting interplay between H2O and CH4 in the near-infrared (NIR),” Latouf tells Universe Today. “While we knew that the spectral features H2O and CH4 overlap heavily in the NIR, and would probably cause some issues with detectability, what we didn’t realize was how much that effect mattered. In fact, we find that at sufficiently high CH4, the signal-to-noise ratio (SNR) required to strongly detect H2O shoots up, and the same vice versa. Essentially, we need to be careful before claiming a planet has no H2O or CH4, because if both are present, we might be missing one! There are follow up studies happening currently, led by my fantastic post-bac Celeste Hagee, studying how the detectability of biosignatures in the NIR changes if we add CO2 into the mix!”

Along with building off previous BARBIE studies, this study focuses on contributing to the planned NASA Habitable Worlds Observatory (HWO) mission, which was recommended by National Academies of Sciences, Engineering, and Medicine (NASEM) Decadal Survey on Astronomy and Astrophysics 2020 and is currently planned to launch sometime in the 2040s. The goal of HWO will be to analyze 25 potentially habitable exoplanets, which contrast past and current exoplanet-hunting missions like NASA’s Kepler and NASA’s TESS (Transiting Exoplanet Survey Satellite) missions, respectively, whose objectives were to locate and identify as many exoplanets as possible.

Artist’s rendition for NASA’s Habitable Worlds Observatory, which is slated to launch in the 2040s with the goal of analyzing 25 potentially habitable exoplanets for biosignatures along with conducting other incredible science about our place in the cosmos. (Credit: NASA’s Goddard Space Flight Center Conceptual Image Lab)

HWO will use a combination of the direct imaging method to find the exoplanets and its spectroscopy instruments to analyze their respective atmospheres for biosignatures, specifically oxygen and methane. Along with identifying and analyzing potential habitable exoplanets, the other science goals include galaxy growth, element evolution from the Big Bang until now, and our solar system and its place in the universe. Therefore, what next steps need to be taken for BARBIE to become a reality on a future exoplanet imaging mission like HWO?

“The reason why BARBIE is useful is because it provides a huge swath of information about lots of parameter space very quickly – that means we can use that data to build future telescopes!” Latouf tells Universe Today. “For instance, if we’re trying to understand whether we need a 20% or a 40% coronagraph in order to strongly detect biosignatures in the optical regime, we can look at how the 20% and 40% influences detection of biosignatures, and from there make the decision on whether the science benefit of a 40% is worth the increased cost.”

This isn’t the first time scientists have postulated that methane might be a key indicator of life on exoplanets, as a 2022 study published in the Proceedings of the National Academy of Sciences (PNAS) discussed how atmospheric methane should be considered an exoplanet biosignature and be targeted by space telescopes like NASA’s James Webb Space Telescope (JWST). Within our own solar system, methane is a key component of Saturn’s largest moon, Titan, with researchers hypothesizing that its crust could contain methane. Additionally, Mars experiences seasonal changes in methane gases that keep scientists puzzled regarding its origin. Therefore, what is the significance of identifying methane on Earth-like exoplanets?

Latouf tells Universe Today, “CH4 is a contextual biosignature – if we find sufficient amounts of CH4 and O2 in an atmosphere together, it means the atmosphere is in disequilibrium. That means that there must be something PRODUCING those levels of CH4 and O2, and depending on the abundances of each, the signs would point to some form of life behind that production.”

This study comes as the number of confirmed exoplanets currently totals 5,832 with 212 being designated as terrestrial (rocky) exoplanets, or exoplanets that are Earth-sized or smaller. A primary example of terrestrial exoplanets includes the TRAPPIST-1 system that resides just over 40 light-years from Earth and is currently hypothesized to host seven Earth-sized exoplanets with at least three orbiting in its star’s habitable zone, which is the right distance from the star to support surface liquid water like Earth.

The closest known terrestrial exoplanet to Earth is Proxima Centauri b, which is 4.24 light-years from Earth and orbits within its star’s HZ despite its orbit only being 11.2 days. However, this also means Proxima Centauri b is blasted by ultraviolet radiation, meaning its surface might not be suitable for life as we know it. Therefore, does Latouf believe we will ever find life on Earth-like exoplanets and which Earth-like exoplanets are particularly interesting to her?

“In my opinion, I think that we will,” Latouf tells Universe Today. “Will that happen in my lifetime? That I’m not sure of – but I do believe we’re going to find life eventually! Although it’ll sound boring the most Earth-like planet I’m interested in is…Earth. We have this wonderful gift in this planet, with all the exact right conditions. We need to be making sure we’re preserving it and understanding our own planet before we dive into the search for others!”

For now, BARBIE remains on the drawing board, but it demonstrates the tireless commitment of the scientific community to improve upon previous designs with the goal of answering whether life exists beyond Earth and throughout the cosmos. Going forward, the authors note that future work will continue to enhance BARBIE’s capabilities, including detecting all molecules across HWO’s entire wavelength range like ultraviolet in addition to optical and NIR. They also plan to test whether coronagraph detectors, which block light from a star to both reveal and improve exoplanet analysis, are suitable for identifying molecules in an exoplanet’s atmosphere.

Latouf concludes by telling Universe Today, “I want to emphasize that it’s very easy to see a completed paper and think to yourself, especially as an early career, “I could never do that.” BARBIE was a project that was created by a team – sure, I put my special branding on it and did the work, but the project was born of open collaboration and communication. The process of doing the work for BARBIE1, 2, and 3 took about 3.5 years, and many, many setbacks. This work is hard, it’s not easy, and no one finds it easy. All this to say – if you’re working on something, and looking at others thinking you can’t do it like they can, just know: they’re learning and growing too, and science is never as easy as it looks.”

Is methane the correct biosignature to identify life as we know it on exoplanets and how will BARBIE help the continued search for life beyond Earth in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Is Methane the Key to Finding Life on Other Worlds? appeared first on Universe Today.

An expert in energy technologies uses AI tools to investigate the impact of extreme weather on solar-powered and electrified homes and uncover their unique vulnerabilities and develop insights on how they handle harsh conditions.

In the more than 60 years since the Space Age began, humans have sent more than 6,740 rockets to space. According to the ESA’s Space Debris Office, this has resulted in 56,450 objects in orbit; about 36,860 of these objects are regularly tracked and maintained in a catalog, while 10,200 are still functioning. The rest is a combination of spent rocket stages, defunct satellites, and pieces of debris caused by unused propellant exploding and orbital collisions. This is leading to a cascade effect known as Kessler Syndrome, where the amount of debris in orbit will lead to more collisions and more debris.

What’s worse, the situation is only projected to get worse since more launches are expected with every passing year. Last year, space agencies and commercial space companies conducted a record-breaking 263 launches, with the U.S. (158) and China (68) leading the way. And with future break-ups occurring at historic rates of 10 to 11 per year, the number of debris objects in orbit will continue to increase. According to a new study by a team from the University of British Columbia (UBC), this also means that debris falling to Earth will have a 1 in 4 chance per year of entering busy airspace.

Ewan Wright, a doctoral student in UBC’s Interdisciplinary Studies Graduate Program, led the research. He was joined by Associate Professor Aaron Boley of the UBC Department of Physics and Astronomy and the co-director of The Outer Space Institute (OSI) at UBC, and Professor Michael Byers, the Canada Research Chair in Global Politics and International Law at the UBC Department of Political Science. The paper detailing their findings, “Airspace closures due to reentering space objects,” recently appeared in Scientific Reports, a journal maintained by Nature Publishing.

Artist’s impression of the orbital debris problem. Credit: UC3M

Traditionally, the discussion of space junk and the Kessler Syndrome has focused on how debris in orbit will pose a hazard for future satellites, payloads, and current and future space stations. In 2030, NASA and its many partnered space agencies plan to decommission the International Space Station (ISS) after thirty years of continuous service. However, this situation will also mean that more debris will be deorbiting regularly, not all of which will completely burn up in Earth’s atmosphere.

While the chance of debris hitting an aircraft is very low (one in 430,000, according to their paper), the UBC team’s research highlights the potential for disruption to commercial air flights and the additional costs it will lead to. The situation of more launches and more hazards is illustrated perfectly by the “rapid unscheduled disassembly” (RUD) of the Starship on January 16th, during its seventh orbital flight test. The explosion, which happened shortly after the prototype reentered Earth’s atmosphere, caused debris to rain down on the residents of the Turks and Caicos. Said Wright in a UBC News release:

“The recent explosion of a SpaceX Starship shortly after launch demonstrated the challenges of having to suddenly close airspace. The authorities set up a ‘keep out’ zone for aircraft, many of which had to turn around or divert their flight path. And this was a situation where we had good information about where the rocket debris was likely to come down, which is not the case for uncontrolled debris re-entering the atmosphere from orbit.”

A similar situation happened in 2022 when the spent stages of a Chinese Long March 5B (CZ-5B) weighing about 20 metric tons (22 U.S. tons) prompted Spanish and French aviation authorities to close parts of their airspace. If spent stages and other payloads have a low enough orbit, they can reenter Earth’s orbit uncontrolled, and large portions may make it to the ground. In addition to the record number of launches last year, there were also 120 uncontrolled rocket debris re-entries while more than 2,300 spent rocket stages are still in orbit.

Debris from the SpaceX Starship launched on January 16th, spotted over the Turks and Caicos Islands.
Credit: Marcus Haworth/Reuters

According to the International Air Transport Association, passenger numbers are expected to increase by almost 7% this year. With rocket launches and commercial flights increasing at their current rate, Wright and his colleagues say that action must be taken to mitigate the potential risks. As part of their study, the team selected the busiest day and location for air traffic in 2023, which was in the skies above Denver, Colorado – with one aircraft for every 18 square km (~7 mi2). They then paired this to the probability of spent rock stages reentering Earth’s atmosphere (based on a decade of data) above the flights.

With this as their peak, they calculated the probability of rocket debris reentering the atmosphere over different air traffic density thresholds. Their results showed that for regions experiencing 10% peak air traffic density or higher, there was a 26% chance of deorbited rocket debris entering that airspace. “Notably, the airspace over southern Europe that was closed in 2022 is only five percent of the peak,” said Wright. “Around the world, there is a 75-per-cent chance of a re-entry in such regions each year.”

At present, whenever orbital debris reenters the atmosphere around busy airspace, aviation authorities will respond by diverting flight paths, closing airspace, or taking the risk of allowing flights to continue. “But why should authorities have to make these decisions in the first place? Uncontrolled rocket body re-entries are a design choice, not a necessity,” said Dr. Boley. “The space industry is effectively exporting its risk to airlines and passengers.”

One possibility is to design rocket stages to reenter the atmosphere in a controlled way so they can crash into the ocean far away from busy air traffic lanes. However, this solution requires collective international action. “Countries and companies that launch satellites won’t spend the money to improve their rocket designs unless all of them are required to do so,” said Dr. Byers. “So, we need governments to come together and adopt some new standards here.”

Further Reading: UBC, Scientific Reports

The post Space Junk Could Re-Enter the Atmosphere in Busy Flight Areas appeared first on Universe Today.

The Quipu superstructure is enormous, spanning 1.4 billion light years – and it could violate one of our fundamental assumptions about the universe

Pig gelatin can be used to make a robotic arm that safely biodegrades, rather than adding to landfill

Scientists have successfully developed a gastric cancer model using 3D bioprinting technology and patient-derived cancer tissue fragments. This innovative model preserves the characteristics of actual patient tissues and is expected to rapidly evaluate and predict individual patient drug responses.