Monday, March 28, 2022

Cheese Ends, 20220328


 

(Picture from here.)

 

Our local grocery store has an item in the deli called “cheese ends.” These are the ends of cheese wheels of blocks that become too small to cut easily. They bundle them together and sell them as a package. Good cheese in bits and pieces but of good quality.

 

That’s what I’m calling this new section. Rather than the long-winded and exhaustive approach to a single subject, these are interesting bits and pieces that came over my desk, packaged up for your consumption.

 

Before we get started, a shout out to two readers in Luxembourg and Australia. I watch my tiny set of sales closely and I’ve been seeing someone out there buying one book after another. As if, *gasp*, they might be reading them.

 

Thank you. I think I’ve doubled my readership.

 

Both of you—no, I have to correct that. The four of you—who read this blog know I have no trouble acknowledging the fact of climate change—so far without the help of magical thinking. There are a lot of greenhouse gases to consider but the two main ones under discussion are CO2 and methane. (CH4.) Emission of CO2 is pretty well nailed down. Partly because there is so much being emitted that we can see where and partly because the CO2 measured is easily discerned from the CO2 coming from natural sources.

 

Methane is a harder nut to crack. Methane derives from a lot of natural sources: disintegration of peat bogs, post-forest fire recovery, natural seepage from ancient deposits. But it is also pumped out of the ground both for its own sake and as a byproduct of oil extraction. This is important because though the volume of emissions is relatively low, methane hits far outside its weight class in its climate impact—as much as 30-80 times the effect of CO2. It’s low-hanging fruit as far as mitigating climate change.

 

A recent study has used a satellite has shown on the order of 1800 “ultra-emitters”—large methane plumes from single sources. Two-thirds were from the oil and gas industry (surprise!) and three countries, including the US, were responsible for the majority of the problem.

 

While this isn’t happy news, it’s the kind of issue that can be addressed. It would be nice if, maybe, that $20 billion in subsidies for the O&G industry could be made contingent on them cleaning up their act.

 

When we read about stone tool culture, we get the idea that all humans derived the same tools over time. This is a Clovis point. This is an Oldowan chopping tool. This is an Acheulean hand ax. As if all humans in the culture pick up the new technology at the same time.

 

This is like saying that as soon as oil paints were created, all artists in the world became oil painters overnight. There are a lot of ways to create art. There are a lot of ways to create tools. Not all of them survive for us to unravel them in the modern world.

 

Enter the site in Xiamabei, China.

 

40,000 years ago, the people in this locale used tiny bladelets of stone less than four centimeters long to do everything: cut meat, whittle wood, scrape hides. Not big, heavy hand-axes. But tiny bits hafted onto bone handles apparently using ochre as an adhesive component. No one else has ever seen these sorts of tools used at this period. Not Neanderthal, Denisovan, or Homo sapiens. There’s no direct evidence of who these people were, either, though there is evidence of some contemporary humans a few hundred kilometers away.

 

What I find interesting here is that humans will create tools out of local stuff and for their own needs in isolation. Sure, there was probably an invention of the Clovis point and it spread around. But if it hadn’t, enterprising humans would have created something different that worked as well.

 

Years ago, Stephen Jay Gould was on an NPR talk show and I managed to get in. The question I put to SJG was, okay, the dinosaurs (and a lot of other species) managed to get wiped out at the end of the Cretaceous. But that’s only half the story and the least interesting half at that. The important part is why did birds and mammals survive? What made them so special? He did not have an answer—which is not surprising since there is no good answer. Dinosaurs, pterosaurs, ammonites, and marine reptiles were eliminated, while mammals, birds, crocodiles, and turtles survived. How come?

 

Recently, though, there is a hint.

 

It looks now like the timing of the Chicxulub Meteor might have had something to do with the selectivity of the extinction. Analyzing fossilized fish killed in the impact, the meteor struck in the spring, smack in the middle of Northern Hemisphere reproductive activities. Animals that required long hatching times and rearing, like non-avian dinosaurs, would have been disproportionately affected compared to short-timers like small mammals and birds.

 

Animals, however, in the Southern Hemisphere would have been getting ready to bed down for the winter and presumably be better able to survive the effects.

 

It’s not a perfect explanation but it’s a step in the right direction.

 

In the category of flat out strange experiments, a Nature article described a team that took an antiproton—an antiparticle of the mass of a proton but with a negative charge—and put it in orbit around a helium ion. Then, they watched it dance through the orbitals spitting out photons. The reason they tried something like this is to get very precise measurements of the qualities of antiparticles. One big hole in modern physics is why is there a vast preponderance of normal matter instead of an even mix of normal matter and antimatter.

 

But it’s a strange idea for essentially a negatively charged proton wandering through the electron orbitals of a helium atom like a fat electron. I can’t get my mind around the quantum mechanics of that. What sort of bonds would be possible? Would a covalent bond between a carbon with antiprotons and an oxygen with electrons be possible? I.e., would they instantly annihilate one another or would they be able to share for some finite period of time? The mind boggles.

 

I’ve made allusions in my fiction that I think language didn’t evolve by itself but had antecedents in song and gesture—we sang before we spoke.

 

A recent paper from the Royal Society suggests that gestures may predate spoken language.

 

This is not a new idea. Scientists have hypothesized this since the eighteenth century. But it’s been hard to get any hard evidence. These researchers set up what I would consider a fairly rigorous mechanism. They created two groups of producers from Vanatau that would attempt to present a word both orally and gesturally. Two groups of receivers were matched from Australian undergraduate students by age and sex. The producers’ efforts were recorded. Gestural production was recorded without sound. Vocal production was recorded without video. The matched interpreters were to attempt to guess the words being presented in the recording. There were Australian/Australian combinations as well as Vanatau/Australia combinations. The details are in the paper.

 

The results were interesting. First, there was a significant signal similarity in the way the producers attempt to communicate the same words. Second, gestural modality was more successful than vocal modality. Third, the gestures used to communicate had a significant commonality for the same words. There was signal similarity in both vocal and gestural communication but there was more commonality with gestures than with vocals.

 

So, maybe we didn’t only sing before we spoke, maybe we gestured.

 

Speaking of gestures—are at least manual dexterity—there is a new paper that investigates some interesting wrinkles in our hands.

 

Archeologists and paleontologists have long discussed why Homo sapiens, out of all the primates, get the fat end of the stick. Big brains? Upright posture? Ability to sweat well? Our hands?

 

All of these have been important and none of them are more important than our lovely, lovely hands. We have a precision grip, a wonderful combination of stability, strength, and flexibility. How do we do that?

 

This paper investigates a small piece of that action: how fingers apply force at the tip. If you view a finger as a set of cylinders held in place with a mechanical linkage, one interesting feature is that as the force increases, the assembly tends to suddenly buckle. Human fingers don’t do that. Why?

 

It turns out that maintaining a strong precision grip is a dance between stability and strength that requires fine neural control. In effect, the system positions the hand in a way as to prevent buckling such that the mechanics of the system provide the stability.

 

Moving off-planet, unless you’ve been living under a rock, there has been a continuing buzz for some time now about the detection of gravity waves.

 

These were postulated by Einstein long ago. If space-time acts as a sort of fabric warped by mass—resulting in gravity—then sufficiently large changes in energy or mass could cause a shift in that fabric. A wave analogous to the ripples in a pond caused by dropping a rock. Those waves could propagate through space at the speed of light.

 

Two black holes merging could produce such ripples and these were detected at LIGO (Laser Interferometer Gravitational-Wave Observatory) when it first became operational.

 

LIGO operates with two perpendicular lasers interfering with one another. A gravity wave is a distortion in space-time and when it rolls over LIGO, it distorts space, causing the space between the lasers to stretch and contract. This changes the interference pattern and, lo, gravity waves are detected.

 

The very first gravity waves were detected in 2015 resulting from the merger of two black holes of 35 and 30 times the mass of the sun at a distance of 1.4 billion light-years. The energy carried away from the event by gravity waves was 50 times greater than the combined power of all light radiated by all stars in the observable universe. While that is an inconceivable amount of energy, gravity waves follow the inverse square law such that by the time it reached us, the amount of energy contained was very, very small.

 

One wonders what it would have been like to be just a few light-years distance. Would there be anything left?

 

Regardless, this is the problem faced by LIGO and other like gravity wave observatories. They need to be incredibly sensitive even to detect fairly large events.

 

Enter the Moon.

 

Researchers at the University College, London, have come up with a way of measuring quite small gravity waves by measuring the perturbations in the Moon’s orbit. LIGO and its sister observatories are sensitive to specific frequencies of events. Slower events, such as those that may have occurred in the early universe, are beyond them.

 

But the moon has a 28-day orbit, translating to a frequency of interest to early universe scientists. The device is right there to be used. All we need is to instrument it.

 

Finally, some very interesting news on the origin of life front.

 

I talked a little about the origins of life back in the day. (See here and  here.) To boil it down, there are two very basic actions life has to execute: metabolism and reproduction. There have been discussions as to whether this required a cell boundary or not. Whether the metabolism came first and reproduction came later. Whether reproduction came first, etc.

 

One continuing interest is if RNA came first. RNA is interesting. It can be used to retain information. (RNA viruses do exactly that.) It has some enzymatic capabilities. It’s a good candidate. But RNA is not terribly stable.  One of the discussions involves how RNA information had to be handed over to DNA. DNA isn’t all that stable, either, but it is more stable than RNA.

 

Researchers at the University of Tokyo have created RNA that appears to be able to engage in natural selection. This means RNA can reproduce, diversify over generations, develop complexity, and be subject to Darwinian evolution.

 

This is big for several reasons. As stated previously, RNA has some enzymatic capability as well. Thus, this research presents the exciting possibility that reproduction and metabolism could have arisen together. We just need a boundary to contain it and we have a very simple living cell. Maybe. We’ll see.

 

That’s it for this edition of Cheese Ends. The next will come… someday.

1 comment:

  1. Interesting post, Steve. The cheese ends format harkens back to the afternoons of yore exploring all sorts of random topics in your office... I miss our discourse and the days of whinge. Hope you are well!

    ReplyDelete