Meaningful ink

It's a little odd that someone as center-of-attention-phobic as I am has chosen something that is bound to garner close looks.  I'm referring to my tattoos, which are obvious and colorful -- and include a full sleeve, so they're a little hard to hide.

Virtually everyone who comments on them, however, is complimentary.  With good reason; my artist, James Spiers of Model Citizen Tattoos in Ithaca, New York, is -- in a word -- brilliant, and realized my vision of what I wanted just about perfectly.  

Just after it was finished

Not everyone's a fan, of course.  I was given the stink-eye by a sour-faced old lady in a local hardware store a while back, who informed me that having tattoos meant I was going to hell.

My response was, "Lady, that ship sailed years ago."

But if I do end up in hell because of my ink, I'll have a lot of company.  Not only is tattooing pretty common these days -- since I got my first one, about twenty years ago, it's gone from being an infrequent sight to just about everywhere -- humans have been decorating their bodies for a long time.  Ötzi "the Ice Man," a five-thousand-year-old body found frozen in glacial ice on the Austrian-Italian border, had 61 tattoos, mostly on his legs, arms, and back.  (Their significance is unknown.)  In historical times, tattooing has been observed in many cultures -- it was widespread in North and South American Indigenous people and throughout east Asia and Polynesia, which is probably how the tradition jumped to Europe in the eighteenth century (and explains its associations with sailors).

The role of self-expression in tattoos varies greatly from person to person.  Ask a dozen people why they chose to get inked and you'll get a dozen wildly different answers.  For me, it's in honor of my family and ethnic roots; the Celtic snake is for my wildlife-loving, half-Scottish father, the vines for my gardener mother.  But the reasons for getting tattooed are as varied as the designs are.

The reason all this comes up is because of a discovery that was described this week in the Journal of Archaeological Science of the oldest-known tattoo tools, some sharpened turkey leg and wing bones found near Fernvale, Tennessee that predate Ötzi by over five hundred years.  The hollow pointed tips of the bone tools still contained residue of black and red pigments, and the microscopic wear on the tips and edges match that found on tattoo tools found at other sites around the world.

The ordeal of being jabbed over and over with a sharpened bird bone, though, sounds a lot more painful than what I underwent, which was bad enough.

But it was worth it.  After I stopped screaming.

In any case, I find it fascinating how old the drive to adorn our bodies is, and also that the designs had (and have) such depth of meaning that people were willing to wear them permanently.  For myself, I've never regretted them for a moment; I'm proud of my ink, whatever the sour-faced little old ladies of the world might think of it.  And knowing that what I have is part of a tradition that goes back at least six thousand years gives me a connection to the rituals and culture of the past.

And for me, that's something to cherish.  Even if I do end up in hell because of it.

***********************************

Saber-toothed tigers.  Giant ground sloths.  Mastodons and woolly mammoths.  Enormous birds like the elephant bird and the moa.  North American camels, hippos, and rhinos.  Glyptodons, an armadillo relative as big as a Volkswagen Beetle with an enormous spiked club on the end of their tail.

What do they all have in common?  Besides being huge and cool?

They all went extinct, and all around the same time -- around 14,000 years ago.  Remnant populations persisted a while longer in some cases (there was a small herd of woolly mammoths on Wrangel Island in the Aleutians only four thousand years ago, for example), but these animals went from being the major fauna of North America, South America, Eurasia, and Australia to being completely gone in an astonishingly short time.

What caused their demise?

This week's Skeptophilia book of the week is The End of the Megafauna: The Fate of the World's Hugest, Fiercest, and Strangest Animals, by Ross MacPhee, which considers the question, and looks at various scenarios -- human overhunting, introduced disease, climatic shifts, catastrophes like meteor strikes or nearby supernova explosions.  Seeing how fast things can change is sobering, especially given that we are currently in the Sixth Great Extinction -- a recent paper said that current extinction rates are about the same as they were during the height of the Cretaceous-Tertiary Extinction 66 million years ago, which wiped out all the non-avian dinosaurs and a great many other species at the same time.  

Along the way we get to see beautiful depictions of these bizarre animals by artist Peter Schouten, giving us a glimpse of what this continent's wildlife would have looked like only fifteen thousand years ago.  It's a fascinating glimpse into a lost world, and an object lesson to the people currently creating our global environmental policy -- we're no more immune to the consequences of environmental devastation as the ground sloths and glyptodons were.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!] 

Thanks for the memories

I've always been fascinated with memory. From the "tip of the tongue" phenomenon, to the peculiar (and unexplained) phenomenon of déjà vu, to why some people have odd abilities (or inabilities) to remember certain types of information, to caprices of the brain such as its capacity for recalling a forgotten item once you stop thinking about it -- the way the brain handles storage and retrieval of memories is a curious and complex subject.

Two pieces of research have given us a window into how the brain organizes memories, and their connection to emotion.  In the first, a team at Dartmouth and Princeton Universities came up with a protocol to induce test subjects to forget certain things intentionally.  While this may seem like a counterproductive ability -- most of us struggle far harder to recall memories than to forget them deliberately -- consider the applicability of this research to debilitating conditions such as post-traumatic stress disorder.

In the study, test subjects were shown images of outdoor scenes as they studied two successive lists of words.  In one case, the test subjects were told to forget the first list once they received the second; in the other, they were instructed to try to remember both.

"Our hope was the scene images would bias the background, or contextual, thoughts that people had as they studied the words to include scene-related thoughts," said Jeremy Manning, an assistant professor of psychological and brain sciences at Dartmouth, who was lead author of the study.  "We used fMRI to track how much people were thinking of scene-related things at each moment during our experiment.  That allowed us to track, on a moment-by-moment basis, how those scene or context representations faded in and out of people's thoughts over time."

What was most interesting about the results is that in the case where the test subjects were told to forget the first list, the brain apparently purged its memory of the specifics of the outdoor scene images the person had been shown as well.  When subjects were told to recall the words on both lists, they recalled the images on both sets of photographs.

"[M]emory studies are often concerned with how we remember rather than how we forget, and forgetting is typically viewed as a 'failure' in some sense, but sometimes forgetting can be beneficial, too," Manning said.  "For example, we might want to forget a traumatic event, such as soldiers with PTSD.  Or we might want to get old information 'out of our head,' so we can focus on learning new material.  Our study identified one mechanism that supports these processes."

What's even cooler is that because the study was done with subjects connected to an fMRI, the scientists were able to see what contextual forgetting looks like in terms of brain firing patterns.  "It's very difficult to specifically identify the neural representations of contextual information," Manning said.  "If you consider the context you experience something in, we're really referring to the enormously complex, seemingly random thoughts you had during that experience.  Those thoughts are presumably idiosyncratic to you as an individual, and they're also potentially unique to that specific moment.  So, tracking the neural representations of these things is extremely challenging because we only ever have one measurement of a particular context.  Therefore, you can't directly train a computer to recognize what context 'looks like' in the brain because context is a continually moving and evolving target.  In our study, we sidestepped this issue using a novel experimental manipulation -- we biased people to incorporate those scene images into the thoughts they had when they studied new words.  Since those scenes were common across people and over time, we were able to use fMRI to track the associated mental representations from moment to moment."

In the second study, a team at UCLA looked at what happens when a memory is connected to an emotional state -- especially an unpleasant one.  What I find wryly amusing about this study is that the researchers chose as their source of unpleasant emotion the stress one feels in taking a difficult math class.

I chuckled grimly when I read this, because I had the experience of completely running into the wall, vis-à-vis mathematics, when I was in college.  Prior to that, I actually had been a pretty good math student.  I breezed through high school math, barely opening a book or spending any time outside of class studying.  In fact, even my first two semesters of calculus in college, if not exactly a breeze, at least made good sense to me and resulted in solid A grades.

Then I took Calc 3.

I'm not entirely sure what happened, but when I hit three-dimensional representations of graphs, and double and triple integrals, and calculating the volume of the intersection of four different solid objects, my brain just couldn't handle it.  I  got a C in Calc 3 largely because the professor didn't want to have to deal with me again.  After that, I sort of never recovered.  I had a good experience with Differential Equations (mostly because of a stupendous teacher), but the rest of my mathematical career was pretty much a flop.

And the worst part is that I still have stress dreams about math classes.  I'm back at college, and I realize that (1) I have a major exam in math that day, and (2) I have no idea how to do what I'll be tested on, and furthermore (3) I haven't attended class for weeks.  Sometimes the dream involves homework I'm supposed to turn in but don't have the first clue about how to do.  Sometimes, I not only haven't studied for the exam I'm about to take, I can't find the classroom.

Keep in mind that this is almost forty years after my last-ever math class. And I'm still having anxiety dreams about it.

What the researchers at UCLA did was to track students who were in an advanced calculus class, keeping track of both their grades and their self-reported levels of stress surrounding the course.  Their final exam grades were recorded -- and then, two weeks after the final, they were given a retest over the same material.

The fascinating result is that stress was unrelated to students' scores on the actual final exam, but the students who reported the most stress did significantly more poorly on the retest.  The researchers call this "motivated forgetting" -- that the brain is ridding itself of memories that are associated with unpleasant emotions, perhaps in order to preserve the person's sense of being intelligent and competent.

"Students who found the course very stressful and difficult might have given in to the motivation to forget as a way to protect their identity as being good at math," said study lead author Gerardo Ramirez.  "We tend to forget unpleasant experiences and memories that threaten our self-image as a way to preserve our psychological well-being.  And 'math people' whose identity is threatened by their previous stressful course experience may actively work to forget what they learned."

So that's today's journey through the recesses of the human mind.  It's a fascinating and complex place, never failing to surprise us, and how amazing it is that we are beginning to understand how it works.  As my dear friend, Professor Emeritus Rita Calvo, Cornell University teacher and researcher in Human Genetics, put it: "The twentieth century was the century of the gene.  The twenty-first will be the century of the brain.  With respect to neuroscience, we are right now about where genetics was in the early 1900s -- we know a lot of the descriptive features of the brain, some of the underlying biochemistry, and other than that, some rather sketchy details about this and that.  We don't yet have a coherent picture of how the brain works.

"But we're heading that direction.  It is only a matter of time till we have a working model of the mind.  How tremendously exciting!"

***********************************

Saber-toothed tigers.  Giant ground sloths.  Mastodons and woolly mammoths.  Enormous birds like the elephant bird and the moa.  North American camels, hippos, and rhinos.  Glyptodons, an armadillo relative as big as a Volkswagen Beetle with an enormous spiked club on the end of their tail.

What do they all have in common?  Besides being huge and cool?

They all went extinct, and all around the same time -- around 14,000 years ago.  Remnant populations persisted a while longer in some cases (there was a small herd of woolly mammoths on Wrangel Island in the Aleutians only four thousand years ago, for example), but these animals went from being the major fauna of North America, South America, Eurasia, and Australia to being completely gone in an astonishingly short time.

What caused their demise?

This week's Skeptophilia book of the week is The End of the Megafauna: The Fate of the World's Hugest, Fiercest, and Strangest Animals, by Ross MacPhee, which considers the question, and looks at various scenarios -- human overhunting, introduced disease, climatic shifts, catastrophes like meteor strikes or nearby supernova explosions.  Seeing how fast things can change is sobering, especially given that we are currently in the Sixth Great Extinction -- a recent paper said that current extinction rates are about the same as they were during the height of the Cretaceous-Tertiary Extinction 66 million years ago, which wiped out all the non-avian dinosaurs and a great many other species at the same time.  

Along the way we get to see beautiful depictions of these bizarre animals by artist Peter Schouten, giving us a glimpse of what this continent's wildlife would have looked like only fifteen thousand years ago.  It's a fascinating glimpse into a lost world, and an object lesson to the people currently creating our global environmental policy -- we're no more immune to the consequences of environmental devastation as the ground sloths and glyptodons were.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!] 

The song of the bat

My favorite animal is the flying fox.

(Don't tell my dogs.)

[Image licensed under the Creative Commons Andrew Mercer (www.baldwhiteguy.co.nz), Grey headed flying fox - AndrewMercer IMG41848, CC BY-SA 4.0]

What's not to like?  They can fly, they get to eat dates and figs all day, and they have the cutest faces ever.

[Image licensed under the Creative Commons Anton 17, Lesser short-nosed fruit bat (Cynopterus brachyotis), CC BY-SA 4.0]

Fruit-eating sky puppies, is how I think of them.

I have to admit, though, that the fruit bats and flying foxes ("megachiropterans," which is Greek for "big hand-wing") are not as astonishingly weird as their cousins, the "microchiropterans" ("little hand-wing") such as the little brown bat (Myotis lucifugus) familiar to us here in the northeastern United States as a nocturnal insect hunter.  I was thinking about these fascinating animals because I'm reading the book Sensory Exotica by Howard C. Hughes, which is about animal sensory systems, and after I said, "Wow!" for the tenth time, I thought they deserved a post.

You probably know that the nocturnal insectivorous bats hunt using sonar -- they emit sounds, then by the echoes locate their prey and scoop it up.  But what you may not have considered is how stunningly complicated this is.  Here are a few things they have to be able to accomplish:

1. Use the echoes from a tiny object like an insect to tell not only what direction it is, but how far away it is.
2. Determine whether the insect is moving toward them or away from them.
3. Determine whether the insect is straight ahead, or to the right or left of them.
4. Decide if the thing they're detecting is an insect at all -- i.e., food -- or something inedible like a fluttering leaf.
5. Given that most bats live in groups -- in the case of the Mexican free-tailed bat (Tadarida brasiliensis) groups of millions in the same cave system -- they have to be able to distinguish the echoes of their own calls from the echoes (and the calls themselves) of their neighbors.
6. Since an echo is much fainter than the original noise, they have to call loudly.  Microchiropteran bats emit calls at about 130 decibels, which is louder than a nearby jet engine or an overamplified rock band.  If their calls weren't so high-pitched -- usually between 30,000 and 40,000 hertz, while even a human with excellent hearing can only detect frequencies lower than 20,000 hertz -- their noises would be deafening.  So how don't they deafen each other, or themselves?

The first one -- the prey range -- they figure out by the delay between the call and the echo.  The closer the insect is, the faster the echo comes back.  We're talking about tiny time intervals, here; for an insect 3.4 meters away, the echo would arrive ten milliseconds after making the call.  So as something gets closer, the echo and the call actually overlap, and the degree of overlap tells the bat it's heading in the right direction.

As far as whether the insect is flying toward or away from the bat, they do this by picking up the Doppler shift of the echo as compared to the pitch of the original call.  You've all heard the Doppler shift; it's the whine of a motorcycle engine suddenly dropping in pitch as it passes you.  So if the pitch of the echo is higher than the pitch of the original call, the insect is coming toward the bat; if it's lower, it's flying away.

Even more astonishing is that they can tell whether an insect is to the right, left, or straight ahead by computing the delay between the echo arriving at their ears.  If it arrives at the right ear first, the insect is the the right, and vice versa; if the echo arrives at both ears simultaneously, it's straight ahead.  Here, we're talking even smaller time intervals; the delay they're sensing is less than a thousandth of a second.

Experiments have shown that bats actually are so sensitive to the quality of the echo that they can tell not only if the sound has echoed off an insect or something else, but if it's an insect, what kind of insect it is.  Experiments have shown that horseshoe bats (Rhinolophus spp.) prefer moths over other types of nocturnal insects, and their sound analysis systems are able to tell the echo coming from the large flapping wings of a moth from the echo coming from the smaller and faster wingbeats of a mosquito or fly.

Okay, now into the part that to me, almost defies belief.  How do they detect their own calls and echoes, and distinguish them from those of their friends?  Each bat recognizes its own call because each call is tuned to a slightly different frequency, and the bat's brain learns to respond to that one frequency and no other.  They can detect a difference between sounds that are only three hertz apart (remember, their calls are in the range of thirty to forty thousand hertz).  But this engenders a problem, the solution to which is mind-boggling.

Remember the Doppler shift?  The echo changes frequency depending on whether the object they're echolocating is coming toward them or away from them.  So how does this not move the frequency of the sound outside of the range the bat is sensitive to?  Put another way, how do they tell that what they're hearing is an echo of their own voice, and not the call of a bat who vocalizes at that (different) frequency?

The answer is that they tune their voices as they go, and do it with a pinpoint accuracy beyond what any trained opera singer could accomplish.  If they hear a sound that could be an echo or could be the voice of a nearby bat, they test it by changing the pitch of their voice.  If the pitch of the echo also changes, it's their voice, not that of another bat.  Further, they tune their voices so that the highest brain response occurs if the conditions are optimal; the echo is exactly what would indicate that it's a bug of the right species coming toward them at a particular speed.  When the frequency of the echo drops into that range, it's like Luke Skywalker using the targeting computer in his X-wing fighter.  Target locked in!  Bam!

Lunchtime.

If you think that's wild, consider the last one.  How does a bat not deafen itself, if its calls are loud enough to create an echo from a tiny object that its sensitive ears can pick up?  Seems like it's a self-limiting system: if the calls aren't loud enough, the echo is too faint; if the calls are sufficiently loud, the call itself will be disastrously loud for the bat's own ears.

This is solved by an ingenious mechanism.  When the bat vocalizes, a set of tiny muscles connected to the bones of the inner ear (which are the same as ours, the hammer, anvil, and stirrup) pull on the bones and move them away from each other, temporarily diminishing the bat's ability to hear.  As soon as the call is made, the muscles relax and the bones move back together, restoring the bat's hearing.  This needs to happen in an astonishingly short amount of time; recall that the time between call and echo is measured in milliseconds.  But this is what they do -- induce deafness for a fraction of a second, and restore hearing in time to pick up the echo!

So that's our look at the astonishing coolness of nature for the day.  We should appreciate bats; not only are they not the bad guys depicted in horror fiction, they are fantastic predators on animals a lot of us don't like -- nocturnal insects.  Microchiropteran bats can eat on the order of three hundred insects an hour, all night long; at night, hunting is pretty much all they do.  The aforementioned enormous colonies of Mexican free-tailed bats are estimated to eat five hundred thousand kilograms of insects every night.

Which, I have to admit, puts even my favorite fruit-eating flying foxes to shame.

***********************************

Saber-toothed tigers.  Giant ground sloths.  Mastodons and woolly mammoths.  Enormous birds like the elephant bird and the moa.  North American camels, hippos, and rhinos.  Glyptodons, an armadillo relative as big as a Volkswagen Beetle with an enormous spiked club on the end of their tail.

What do they all have in common?  Besides being huge and cool?

They all went extinct, and all around the same time -- around 14,000 years ago.  Remnant populations persisted a while longer in some cases (there was a small herd of woolly mammoths on Wrangel Island in the Aleutians only four thousand years ago, for example), but these animals went from being the major fauna of North America, South America, Eurasia, and Australia to being completely gone in an astonishingly short time.

What caused their demise?

This week's Skeptophilia book of the week is The End of the Megafauna: The Fate of the World's Hugest, Fiercest, and Strangest Animals, by Ross MacPhee, which considers the question, and looks at various scenarios -- human overhunting, introduced disease, climatic shifts, catastrophes like meteor strikes or nearby supernova explosions.  Seeing how fast things can change is sobering, especially given that we are currently in the Sixth Great Extinction -- a recent paper said that current extinction rates are about the same as they were during the height of the Cretaceous-Tertiary Extinction 66 million years ago, which wiped out all the non-avian dinosaurs and a great many other species at the same time.  

Along the way we get to see beautiful depictions of these bizarre animals by artist Peter Schouten, giving us a glimpse of what this continent's wildlife would have looked like only fifteen thousand years ago.  It's a fascinating glimpse into a lost world, and an object lesson to the people currently creating our global environmental policy -- we're no more immune to the consequences of environmental devastation as the ground sloths and glyptodons were.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!] 

Dreaming Invisible

What would an artificial intelligence dream about?

We may have just found out.

An AI development company called Nested Minds is working on creating increasingly sophisticated deep learning networks modeled on the connectivity of the human brain, and especially the brain's ability to form links between disparate ideas and images -- something that is a significant part of the creative process, and also seems to account for a lot of dream content.  Their project, called "Huxley," has generated some pretty amazing and provocative pieces.  On their home page, they describe their project this way:

Nested Minds unites an interdisciplinary team of neuroscientists, mathematicians, developers, social scientists, and entrepreneurs with over 100 years of combined experience building predictive analytics and machine learning models across multiple industries...  We designed Huxley, an AI artist who takes concepts rooted in human language and translates them into provocative and daring imagery redefining the boundaries of imagination.

What Huxley excels at is what we would describe in humans as free association.  For example, the word "keyboard" prompted Huxley to come up with an image of a zebra; the link, presumably, was keyboard > black and white > zebra.  A bass guitar generated a fish; bass has both meanings (although pronounced differently).  While this may seem to be a rudimentary sort of punning, it's not so different from what happens during a long, rambling conversation.  I can remember my younger son and I talking and at some point trying to figure out how we got where we ended up, backtracking every link and reconstructing the whole causal chain -- Doctor Who > time travel > wormholes > astronomy > Galileo > the Inquisition > Monty Python > King Arthur > Camelot > Cornwall etc.

What I find absolutely fascinating is that Nested Minds turned Huxley loose on a song -- a new release from Duran Duran called "Invisible."

The result is weird, surreal, beautiful, and a little disturbing.  (The song is pretty awesome, too.)  Watch it and see what you think:

"When you look at Huxley, this is the sort of first new generation of this type of intelligence, but that will grow and be useful in many, many other fields," singer/keyboardist Nick Rhodes said, in an interview in ITV. "It's incredible new technology because before AI has been more mathematical, this one's actually more arts based.  It does actually dream and think in different ways...  I think we've always viewed technology as something that we can use that can really help us.  We're not intimidated by it...  And if you can use it to enhance your toolkit for what you're doing, I think that's fantastic."

Huxley was given two things -- the lyrics, and video clips of the band singing, and with those two inputs it created the entire video.  And while some of the associations you can fathom (such as the keyboard and the bass guitar), others are obscure and/or complex enough to resist parsing.

"They just took those images of us all singing and put them into the program," said band member Roger Taylor.  "And it came out with these incredible kind of ghostly images which kind of blew me away."

Is this creativity -- I mean, of course, on the part of Huxley, not of its creators nor of Duran Duran themselves?  I don't think you can call it anything other than that.  To me, a large part of creativity is novelty; when we say, "wow, that was really creative," we often mean, "I would never have come up with that."  There has to be some technical skill too, of course.  Depicting that novel connection in a vivid manner requires that you have significant ability in your chosen medium, whether it's writing, music, art, or any other creative endeavor.  But simple technical skill isn't enough.  That spark -- that melding of ideas, words, or images in a unique way -- is absolutely essential, or what you have is no more than a rehashing (however well executed) of what you've seen other people do.

It's true in science, too, isn't it?  A really groundbreaking discovery occurs because someone put data together in such a way as to generate an insight no one else had.  As just one of many examples, take Fred Vine's and Drummond Matthews's development of the model of plate tectonics, using data from magnetic traces on the ocean floor, the geology of mountain ranges on opposite sides of the Atlantic Ocean, the prehistoric animal fossils that had been dug up in Africa and South America, and the presence of active volcanoes along the Mid-Atlantic Ridge.  We'd had all of that information prior to Vine and Matthews; but they were the first to have the insight to put the pieces together, and what they came up with revolutionized the whole field of geology.

That's creativity.

But back to Huxley.  What I find most amazing about this is that this is the first attempt at a music video created entirely by an artificial intelligence, so the creative output can only be expected to improve over time.  What will Huxley, or something like it, be creating in ten years?  Fifty years?  A century?

I think we creative types better hold onto our hats, because my guess is that we're seeing something humanity has never seen before -- the creative output of a non-human intelligence.  And what it can teach us about our own creativity might be only the first step into what is truly uncharted territory.

***********************************

Saber-toothed tigers.  Giant ground sloths.  Mastodons and woolly mammoths.  Enormous birds like the elephant bird and the moa.  North American camels, hippos, and rhinos.  Glyptodons, an armadillo relative as big as a Volkswagen Beetle with an enormous spiked club on the end of their tail.

What do they all have in common?  Besides being huge and cool?

They all went extinct, and all around the same time -- around 14,000 years ago.  Remnant populations persisted a while longer in some cases (there was a small herd of woolly mammoths on Wrangel Island in the Aleutians only four thousand years ago, for example), but these animals went from being the major fauna of North America, South America, Eurasia, and Australia to being completely gone in an astonishingly short time.

What caused their demise?

This week's Skeptophilia book of the week is The End of the Megafauna: The Fate of the World's Hugest, Fiercest, and Strangest Animals, by Ross MacPhee, which considers the question, and looks at various scenarios -- human overhunting, introduced disease, climatic shifts, catastrophes like meteor strikes or nearby supernova explosions.  Seeing how fast things can change is sobering, especially given that we are currently in the Sixth Great Extinction -- a recent paper said that current extinction rates are about the same as they were during the height of the Cretaceous-Tertiary Extinction 66 million years ago, which wiped out all the non-avian dinosaurs and a great many other species at the same time.  

Along the way we get to see beautiful depictions of these bizarre animals by artist Peter Schouten, giving us a glimpse of what this continent's wildlife would have looked like only fifteen thousand years ago.  It's a fascinating glimpse into a lost world, and an object lesson to the people currently creating our global environmental policy -- we're no more immune to the consequences of environmental devastation as the ground sloths and glyptodons were.

[Note: if you purchase this book using the image/link below, part of the proceeds goes to support Skeptophilia!] 

Expanding the umwelt

The concept of the umwelt is a little mind-boggling.

It's defined as "the world as perceived by a particular organism."  In superficial terms we know that a dog must perceive life differently than we do.  For example, we know their senses of smell are a lot more keen than ours are, but the magnitude is staggering.  They have about fifty times the number of olfactory receptors than we do (three hundred million as compared to six million), so their world must be as vivid a tapestry of smells as ours is a tapestry of sights and sounds.

While it might be possible to imagine what it's like to have an enhanced sense, what about having a sense we lack entirely?  A number of animals, including sharks, platypuses, and knifefish, have an ability to sense electric fields, so the voltage change in the water around them registers as a sensory input, just as light or sound or taste does for us.  They use this sense to locate prey, because the neuromuscular systems of the animals they're hunting create a weak electrical discharge, which all of these animals can "see."

In the amazing 2015 TED Talk "Can We Create New Senses for Humans?",  neuroscientist David Eagleman explores what it would be like to expand our umwelt.  He has designed a vest, to be worn against the skin, that has a series of motors that create tiny vibrations.  The vest's input can be whatever you want; in one demonstration, sounds picked up by a microphone are the input used to create a pattern of vibrations on the chest and back.  With only a couple of days of training, a profoundly deaf individual was able to translate the patterns into a perception of the sounds, and correctly identify spoken words.

His brain had basically taken a different peripheral input device and plugged it into the auditory cortex!

Experiments with other "peripherals" have included using a pattern of weak electrical tingles transmitted onto the tongue via a horseshoe-shaped flat piece of metal to allow blind people to navigate around objects while walking, and even get good enough with it that they can throw an object into a basket.  One of Eagleman's experiments with the vest trained people using an input from an unidentified source -- all they did was press one of a pair of buttons and found out if their choice was right:

A subject is feeling a real-time streaming feed from the Net of data for five seconds.  Then, two buttons appear, and he has to make a choice.  He doesn't know what's going on.  He makes a choice, and he gets feedback after one second.  Now, here's the thing: the subject has no idea what all the patterns mean, but we're seeing if he gets better at figuring out which button to press.  He doesn't know that what we're feeding is real-time data from the stock market, and he's making buy and sell decisions.  And the feedback is telling him whether he did the right thing or not.  And what we're seeing is, can we expand the human umwelt so that he comes to have, after several weeks, a direct perceptual experience of the economic movements of the planet.

The wildest thing is that the peripheral you add doesn't have to be input; it can be output.  Two different papers, both in the journal Science, have shown that you can add an output device, and like with the inputs -- all it takes is a little training.

In the first, "A Brain-Computer Interface that Evokes Tactile Sensations Improves Robotic Arm Control," test subjects have a computer interface device implanted into their brain, which then translates thoughts into movements of a robotic arm, analogous to what an intact neuromuscular system is doing to our actual arms.  This has been doable for a while, but the advance in this study is that the robotic arm has sensors that provide feedback, again just like our own systems do when working properly.  Think about picking up a coffee cup; you adjust the pressure and position of your grip because you're constantly getting feedback, like the temperature of the cup, the weight and balance, whether your fingers are hanging on well or slipping, and so forth.

Here, the feedback provided by the sensors on the robotic arm cut in half the time taken for doing an action without mishap!  The brain once again picked up very quickly how to use the additional information to make the output go more smoothly.

In the second, people were trained with a "third thumb" -- an artificial extra digit strapped to the hand on the pinky-finger side.  It's controlled by pressure sensors under the toes, so you're using your feet to move something attached to your hand while simultaneously using your brain to control your other hand movements, which seems impossibly complicated.  But within a day, test subjects could perform tasks like building a tower from wooden blocks using the augmented hand... even when distracted or blindfolded!

Study author Paulina Kieliba, of University College - London's Institute of Cognitive Neuroscience, said, "Body augmentation could one day be valuable to society in numerous ways, such as enabling a surgeon to get by without an assistant, or a factory worker to work more efficiently.  This line of work could revolutionize the concept of prosthetics, and it could help someone who permanently or temporarily can only use one hand, to do everything with that hand.  But to get there, we need to continue researching the complicated, interdisciplinary questions of how these devices interact with our brains."

Co-author Tamar Makin summed it up: "Evolution hasn’t prepared us to use an extra body part, and we have found that to extend our abilities in new and unexpected ways, the brain adapts the representation of the biological body."

I think what amazes me most about all this is the flexibility of the brain.  The fact that it can adjust to such radical changes in inputs and outputs is phenomenal.  Me, I'm waiting for something like Tony Stark's suit in Iron Man.  That'd not only allow me to fight crime, but it'd make yard chores a hell of a lot easier.

***********************************

Too many people think of chemistry as being arcane and difficult formulas and laws and symbols, and lose sight of the amazing reality it describes.  My younger son, who is the master glassblower for the chemistry department at the University of Houston, was telling me about what he's learned about the chemistry of glass -- why it it's transparent, why different formulations have different properties, what causes glass to have the colors it does, or no color at all -- and I was astonished at not only the complexity, but how incredibly cool it is.

The world is filled with such coolness, and it's kind of sad how little we usually notice it.  Colors and shapes and patterns abound, and while some of them are still mysterious, there are others that can be explained in terms of the behavior of the constituent atoms and molecules.  This is the topic of the phenomenal new book The Beauty of Chemistry: Art, Wonder, and Science by Philip Ball and photographers Wenting Zhu and Yan Liang, which looks at the chemistry of the familiar, and illustrates the science with photographs of astonishing beauty.

Whether you're an aficionado of science or simply someone who is curious about the world around you, The Beauty of Chemistry is a book you will find fascinating.  You'll learn a bit about the chemistry of everything from snowflakes to champagne -- and be entranced by the sheer beauty of the ordinary.

[Note: if you purchase this book from the image/link below, part of the proceeds goes to support Skeptophilia!]

A little life, rounded with a sleep

An unsolved mystery of biology is the question of why we -- and just about every other animal studied -- have to sleep.

I've looked at this issue before here at Skeptophilia, and from the research I've read, we're no closer to a definitive answer.  There's the physical rest aspect, of course, but I think we can all attest that when you're exhausted, you don't recover equally well by sitting quietly awake for two hours or by taking a two-hour nap.  (In fact, if you're like me, when you're exhausted, sitting quietly for two hours without falling asleep is damn near impossible.)  There's some indication that sleep, especially the REM (rapid eye movement) stage wherein we dream, is critical for memory consolidation.  Other studies have found that during sleep, potentially toxic metabolic byproducts are cleared from the brain and cerebrospinal fluid, so sleep may act as a time for cleaning house.

Or all three.  And probably others.  But even if these are partial answers to the conundrum of sleep, they leave a number of facets of the sleep cycle unaccounted for.  Why, for example, does sleep need vary so greatly?  Elephants in the wild sleep about two hours a day; lions, on the other end of the spectrum, snooze for eighteen to twenty hours a day.  Famously, dolphins and whales do something even stranger.  They let half of their brain sleep at a time -- one side becomes quiescent, then that side wakes up and the other one takes a nap.

[Image licensed under the Creative Commons Jamain, Sleeping man J1, CC BY-SA 3.0]

Recent studies have shown that however far you go down the animal-brainpower-scale, they still sleep.  Insects and other arthropods sleep.  Even roundworms do.  One difficulty is that at that stage, it's a little hard to define what sleep is; certainly, the mental activity isn't going to be closely analogous to what goes on in a human's brain during the sleep cycle.  So most biologists use a functional definition: sleep is occurring if (1) the animal becomes quiet and hard to rouse, (2) the behavior is on some kind of a circadian rhythm, and (3) if you disturb the animal's sleep one day, they make up for it by sleeping longer the next day (something called sleep homeostasis).  These are sufficient to differentiate it from other behaviors that might mimic some aspects of true sleep -- hibernation, coma, anesthetization, inebriation, fainting, and so on.

This generates a fascinating result when you look at some of the simplest animals in the world; because a recent paper in the journal Science Advances has demonstrated that by this definition, hydras sleep.

Hydras are a group of freshwater animals in the Phylum Cnidaria, and thus are related to jellyfish, sea anemones, and corals.  This generates a difficulty if you try to apply any brain-based evolutionary reason for the ubiquity of sleep, because hydras don't have a brain.  They have a decentralized nerve net with no central nervous system whatsoever.  And yet, they undergo behavior that meet all three of the criteria of the functional definition for sleep.

This not only raises some interesting questions about the purpose of sleep, it brings up an entirely different one for the evolutionary biologists.  When did sleep evolve?  There's a general rule that the more ubiquitous a feature is (be it an organ, a protein, a gene, a behavior, whatever), the older it is evolutionarily and the more important it is to survival.  By this argument, sleep is really critical (which we already sort of knew), and it's really old.  Hydras are almost as distant as you can get from mammals on the family tree of Kingdom Animalia; our last common ancestor with hydras lived at least five hundred million years ago.  Amongst animals, only sponges are more distantly related.  It is possible that sleep is not a conserved feature -- that it was evolved independently on more than one of the branches of the family tree -- but in my mind, given the fact that every animal studied shows sleep behavior, it seems like it requires a great many more ad hoc assumptions to claim that sleep evolved over and over than it does to assert that we all inherited it from a common ancestor a very long time ago.

Nota bene: you might be thinking that the same could be said for the presence of eyes, but eyes almost certainly evolved separately in different groups.  We can tell this because however functionally similar the eyes of (for example) humans, flies, flatworms, and squids are, they are structurally different.  It may be that they all come from a common ancestor with light-sensing patches of some sort, but if so, in the interim each branch of Kingdom Animalia refined those structures in entirely different ways.  The same, by the way, is true of wings and the presence of flight in a number of different animal groups.

So the discovery that hydras sleep makes a curious question even curiouser.  Clearly, if sleep aids higher brain functioning and memory consolidation in humans, those were advantages it gained us much later, because as I mentioned, hydras don't even have brains.  The presence of sleep behavior in hydras and other simple animals points to it having a function in maintaining metabolism, so perhaps the "sleep as time to clean house" answer will turn out to be closer to the universal answer.

And who knows?  Maybe the next thing they'll find out is that sponges sleep, or that amoebas sleep.  At that point, we'll have a whole new set of questions, because those are organisms that not only lack a brain, but don't have nerves at all.  But given the ubiquity of snoozing in the animal kingdom, I actually wouldn't be surprised if it were true.

***********************************

Too many people think of chemistry as being arcane and difficult formulas and laws and symbols, and lose sight of the amazing reality it describes.  My younger son, who is the master glassblower for the chemistry department at the University of Houston, was telling me about what he's learned about the chemistry of glass -- why it it's transparent, why different formulations have different properties, what causes glass to have the colors it does, or no color at all -- and I was astonished at not only the complexity, but how incredibly cool it is.

The world is filled with such coolness, and it's kind of sad how little we usually notice it.  Colors and shapes and patterns abound, and while some of them are still mysterious, there are others that can be explained in terms of the behavior of the constituent atoms and molecules.  This is the topic of the phenomenal new book The Beauty of Chemistry: Art, Wonder, and Science by Philip Ball and photographers Wenting Zhu and Yan Liang, which looks at the chemistry of the familiar, and illustrates the science with photographs of astonishing beauty.

Whether you're an aficionado of science or simply someone who is curious about the world around you, The Beauty of Chemistry is a book you will find fascinating.  You'll learn a bit about the chemistry of everything from snowflakes to champagne -- and be entranced by the sheer beauty of the ordinary.

[Note: if you purchase this book from the image/link below, part of the proceeds goes to support Skeptophilia!]

Mind over matter

Do you want to learn a new skill?  Something that will make you super popular at parties?

Do I have an opportunity for you.

I found a site that gives a set of step-by-step instructions for learning...

... telekinesis.

Yes, telekinesis, the skill made famous in the historical documentary Carrie wherein a high school girl got revenge on the classmates who had bullied her by basically flinging heavy objects at them with her mind and then locking them inside a burning gymnasium.  Hating bullies as I do, I certainly understand her doing this, although it's probably a good thing this ability isn't widespread.  Given how fractious the current political situation is, if everyone suddenly learned how to move things with their minds, the United States as viewed from space would probably look like a huge, whirling, debris-strewn hurricane of objects being thrown about every time Kevin McCarthy or Nancy Pelosi say anything.

But if you'd like to be able to do this, you can learn how at the aptly named site HowToTelekinesis.com.  But to save your having to paw through the site, I'll hit the highlights here.  You can try 'em out and afterwards report back if you had any success in, say, levitating your cat.

Polish spiritualist medium Stanislawa Tomczyk levitating a pair of scissors that totally was not connected to a piece of thread tied to her fingers [Image is in the Public Domain]

Step one, apparently, is that you have to believe that there is no external reality, because otherwise "your logical mind will be fighting your telekinesis endeavors every step of the way."  I know this would be a problem for me, not least because if there's no external reality, you have to wonder what it is exactly we're supposed to be telekinesis-ing.  In any case, the author of the website suggests that you can accomplish this by studying some quantum physics, because quantum physics tells us the following:

Everything we see, hear, feel, taste and smell is light and energy vibrating at a fixed frequency.  This energy is being projected from within, both individually and collectively.  Our energy projection is reflected back and interpreted and perceived as “real” via the mind through our five senses.  That is the condensed version of reality.

The problem is, quantum physics doesn't tell us any such thing, as anyone who has taken a college physics class knows.  Quantum physics describes the behavior of small, discrete packets of energy ("quanta") which ordinarily only have discernible effects in the realm of the submicroscopic.  It is also, in essence, a mathematical model, and as such has nothing whatsoever to do with an "energy projection (being) reflected back and interpreted and perceived as real by the mind."

Whatever the fuck that even means.  But apparently if you're inclined to learn telekinesis, this allows you to interpret the findings of physics any way that's convenient for you.

Oh, and we're told that it also helps to watch the woo-woo documentary extraordinaire What the Bleep Do We Know?, which was produced by J. Z. Knight, the Washington-based loon who claims to channel a 35,000 year old guy from Atlantis named "Ramtha."  The author waxes rhapsodic about how scientifically accurate this film is, despite the fact that damn near everything in the film is inaccurate at best and an outright lie at worst.

Step two is understanding your "telekinesis toolkit," which includes "empathy, mindset, and energy."  They explain it this way:

Imagine feelings being the words spoken on your phone, and empathy is the signal or wire connecting you.  Your mindset is the phone itself and energy is the electricity used to run it.  You have to have a phone, signal and power to communicate.  A lame phone, weak signal or low battery will make doing telekinesis nearly impossible.

I daresay it will.

Step three is finding a good mentor.  Since these mentors aren't free, let's just say that I had a sudden "Aha" moment when I got to this point.  The website tells us that the best mentors are at the Avatar Energy Mastery Institute, where we can learn the following:

You will learn all about energy, chakras, clairvoyance, out of body travel, mind and soul expansion, healing, higher-self, time travel, lucid dreaming and pretty much everything else a seeker could hope for.  I also know that Ormus from www.SacredSupplements.com really enhances psychic abilities and speeds the learning process.

When I saw "Ormus," something in the back of my brain went off.  I knew I'd seen this before.  And sure enough, a few years ago I did a post on Ormus, which is an acronym standing for "Orbitally Rearranged Monoatomic Elements."  And yes, I know that spells "ORME" and not "ORMUS," but since we're kind of disconnected from reality here anyhow, we'll let that slide.  Evidently the believers in Ormus think that taking this stuff can do everything up to and including (I am not making this up) changing your inertial mass, and I don't mean that you got heavier because you just swallowed something.  They claim that taking Ormus makes your inertial mass smaller, which would be surprising for any supplement not made of antimatter.

And taking antimatter supplements has its own fairly alarming set of risks, the worst of which is exploding in a burst of gamma rays.

So anyway.  I'm thinking that if you do all of this stuff, telekinesis is still going to be pretty much out of the question, as much fun as it could be.  But feel free to give it all a try.  On the other hand, if you're planning on lobbing any heavy furniture my way, please reconsider.  The hate mail I get on a daily basis is bad enough.

***********************************

Too many people think of chemistry as being arcane and difficult formulas and laws and symbols, and lose sight of the amazing reality it describes.  My younger son, who is the master glassblower for the chemistry department at the University of Houston, was telling me about what he's learned about the chemistry of glass -- why it it's transparent, why different formulations have different properties, what causes glass to have the colors it does, or no color at all -- and I was astonished at not only the complexity, but how incredibly cool it is.

The world is filled with such coolness, and it's kind of sad how little we usually notice it.  Colors and shapes and patterns abound, and while some of them are still mysterious, there are others that can be explained in terms of the behavior of the constituent atoms and molecules.  This is the topic of the phenomenal new book The Beauty of Chemistry: Art, Wonder, and Science by Philip Ball and photographers Wenting Zhu and Yan Liang, which looks at the chemistry of the familiar, and illustrates the science with photographs of astonishing beauty.

Whether you're an aficionado of science or simply someone who is curious about the world around you, The Beauty of Chemistry is a book you will find fascinating.  You'll learn a bit about the chemistry of everything from snowflakes to champagne -- and be entranced by the sheer beauty of the ordinary.

[Note: if you purchase this book from the image/link below, part of the proceeds goes to support Skeptophilia!]