Science vs. common sense

A regular reader of my blog commented to me, rather offhand, "To read your posts, you sound awfully sure of yourself.  A little arrogant, even."

I'll leave the last part to wiser heads than mine to answer; I may well have an arrogant streak, and in fact I've remarked more than once that to have a blog at all implies a bit of arrogance -- you have to believe, on some level, that what you think and write will be interesting to enough people to make it worth doing.  But I'd like to leave my own personality flaws aside for a moment, and take a look at the first part of the statement, which is saying something quite different, I think.

In saying that I sound "sure of myself," the fellow who made the comment was saying, so far as I can tell, that I sound like I've got all the answers; that my pronouncements on ghosts and faces on grilled cheese sandwiches and Bigfoot, and -- on a more serious level -- science, ethics, politics, philosophy, and religion, are somehow final pronouncements of fact.  I come across, apparently, as if I'm the last word on the subject, that I've said fiat lux in a booming voice, and now all is light.

Let There Be Light by Shigeru Aoki (1906) [Image is in the Public Domain]

Nothing could be further from the truth, both in fact and in my own estimation.

It's because I have so little certainty in my own senses and my brain's interpretation of them that I have a great deal of trust in science.  I am actually uncertain about most everything, because I'm constantly aware about how easily tricked the human brain is, and how often our "common sense" is wrong.  Here are five examples of just how counter-intuitive nature is -- how easily we'd be misled if it weren't for the tools of science.  I'll present you with some explanations of commonly-observed events -- see if you can tell me which are true and which are false based upon your own observations.

1. Homing pigeons, which can find their way home from amazing distances, are navigating using visual cues such as the positions of the sun, stars, and topographic landmarks.
2. Herding behavior in collies and other sheepdogs is learned very young; herding-breed puppies reared by non-herding breed mothers (e.g. a collie puppy raised by a black lab mother) never learn to herd.
3. A marksman shoots a gun horizontally over a level field, and simultaneously drops a bullet from the same height as the gun barrel. The dropped bullet will hit the ground before the shot bullet because it has far less distance to cover.
4. Flowering plants are temperature-sensitive, and spring-flowering plants like daffodils and tulips recognize the coming of spring (and therefore time to make flowers) when the earth warms up as the days lengthen.
5. Time passes at the same rate for everyone; time is the one universal constant.  No matter where you are in the universe, no matter what you're doing, everyone's clock ticks at exactly the same rate.

Ready for the answers?

All of them are false.

1. Homing pigeons are remarkably insensitive to visual cues.  An experiment, conducted at Cornell University, showed that pigeons' tiny little brains allow them to navigate by picking up the magnetic field of the earth -- i.e., they have internal magnetic compasses.  This ability, called magnetoreception, is shared with a handful of other species (including various turtles, salamanders, fish, bees, and at least one group of motile bacteria).
2. Herding behavior in collies is entirely genetic, not learned (although they refine the skill with training).  Most amazingly, researchers have actually identified the genetic pathways that are responsible for the behavior.  A dog with defects in one or more of those pathways can't learn to herd.  Scientists are still trying to figure out how one set of genes can control a complex behavior like herding ability.  This sheds some interesting light on the nature-vs.-nurture question, though, doesn't it?
3. In this classic thought experiment, the two bullets hit the ground at precisely the same moment.  Vertical velocity and horizontal velocity are entirely independent of each other; the fact that the one bullet is moving very quickly in a horizontal direction, and the other isn't, is completely irrelevant.
4. Temperature has very little to do with the timing of flowering, although a prolonged period of cold can slow down early-flowering plants some.  It used to be thought that flowering plants were timing their flowering cycles based on relative day length, and whether day length was increasing or decreasing; this response (called photoperiodism) clearly has something to do with it, but the mechanism controlling it is still poorly understood.
5. The General Theory of Relativity, which has been experimentally confirmed countless ways, actually says exactly the opposite of this.  What it does say is that the speed of light is constant in all frames of reference, and this has, as one of its bizarre outcomes, that time is completely relative.  Not only might your clock be ticking at a different rate than mine, depending on our relative motion, but events that look simultaneous to you might look sequential to me.  No wonder Einstein won the Nobel, eh?

All of this is just to indicate that our intuition, our "common sense," and even our sensory information, can sometimes be very misleading.  Science is our only way out of this mess; it has proven itself, time and again, to be the very best tool we have for not falling into error because of the natural mistakes made by our brains, the fallacy of wishful thinking and confirmation bias, and being suckered by charlatans and frauds.

A charge levied against science by some people is that it changes; the "truths" of one generation may be different from those of the next.  (I call this the "They Used to Believe the Earth Was Flat" argument.)  Myself, I find this a virtue, not a flaw.  Science, by its nature, self-corrects.  Isn't it better to put your trust in a world view that has the capacity to fix its own errors, rather than one which promises eternal truths, and therefore doesn't change regardless of the discovery of contrary evidence?

I realize that this line of reasoning approaches some very controversial thin ice for many people, and I've no intent to skate any nearer to the edge.  My own views on the subject are undoubtedly abundantly clear.  I firmly believe that everyone buys into the world view that makes the best sense of his/her world, and it would be arrogant for me to tell another person to change -- the most I can do is to present my own understanding, and hope that it will sell itself on its own merits.  And for me, the scientific model may not be perfect, but given the other options, it's the best thing the market has to offer.

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As I've mentioned before, I love a good mystery, which is why I'm drawn to periods of history where the records are skimpy and our certainty about what actually happened is tentative at best.  Of course, the most obvious example of this is our prehistory; prior to the spread of written language, something like five thousand years ago, most of what we have to go by is fossils and the remnants of human settlements.

Still, we can make some fascinating inferences about our distant ancestors.  In Lost Civilizations of the Stone Age, by Richard Rudgely, we find out about some of the more controversial ones -- that there are still traces in modern languages of the original language spoken by the earliest humans (Rudgely calls it "proto-Nostratic"), that the advent of farming and domestication of livestock actually had the effect of shortening our average healthy life span, and that the Stone Age civilizations were far more advanced than our image of "Cave Men" suggests, and had a sophisticated ability to make art, understand science, and treat illness.

None of this relies on any wild imaginings of the sort that are the specialty of Erich von Däniken, Zecharia Sitchin, and Giorgio Tsoukalos; and Rudgely is up front with what is speculative at this point, and what is still flat-out unknown.  His writing is based in archaeological hard evidence, and his conclusions about Paleolithic society are downright fascinating.

If you're curious about what it was like in our distant past, check out Lost Civilizations of the Stone Age!

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

Paleolithic pendant

Our desire to adorn our bodies goes back a very long way.

Decorative clothing, above and beyond any necessity for warmth; cosmetics and hair dyes; more-or-less permanent features like piercings and tattoos; removable bits like jewelry.  The reasons for these probably are as many and varied as the adornments themselves -- self-expression, attractiveness to potential lovers, shows of dominance or wealth, and ritualistic or magical significance probably are four of the more common ones.  But for whatever the reason, I know of no other species that so deliberately and routinely alters their appearance.

The reason the topic comes up is the recent discovery of a 41,500-year-old decorated pendant made of mammoth ivory in Stajnia Cave, a natural rock formation in southern Poland.  The piece is fascinating right from the get-go when you find out that the scientists believe it was fashioned and decorated soon after the unfortunate mammoth's death, so we're talking about humans living in close proximity to one of the most iconic prehistoric mammals.  "An old mammoth tusk would have been unworkable for shaping the Stajnia ornament and carving the punctate motif," said Sahra Talamo of the University of Bologna, who co-authored a paper on the find that was published in Nature this week.  He added that the damp climate of southern Poland at the time made bones and ivory degrade quickly, so it must have been from a recently-deceased animal.

The pendant is oval-shaped, with a large hole (possibly for suspending it on a string so it could be worn) and a series of smaller dots.  Here's a photograph of it:

[Image by Antonino Vazzana]

Also found at the site was an awl made from a horse bone -- possibly the tool used to drill the holes in the ivory pendant.

"Whoever made the artifacts from Stajnia clearly had language, and the nature of the artifacts themselves give us a fascinating insight into what the makers may have valued, and their world," said Laura Basell, of the the University of Leicester.  "It is reasonable to suggest that horses and mammoths were really important in their lives and these objects have meaning on multiple levels."

Well, maybe.  It's kind of thin ice to draw too many inferences about a culture based upon one artifact, or even a bunch of them.  I'm reminded of Horace Mitchell Miner's scathing satire on anthropological papers called "Body Ritual Among the Nacirema," published in 1956, which looks at American culture ("Nacirema," of course, is "American" backwards) solely by drawing inferences upon our artifacts and a slim set of observations of our behaviors.  Here's a passage about what anthropologists might make of our medicine cabinets:

The focal point of the shrine is a box or chest which is built into the wall.  In this chest are kept the many charms and magical potions without which no native believes he could live.  These preparations are secured from a variety of specialized practitioners.  The most powerful of these are the medicine men, whose assistance must be rewarded with substantial gifts.  However, the medicine men do not provide the curative potions for their clients, but decide what the ingredients should be and then write them down in an ancient and secret language.  This writing is understood only by the medicine men and by the herbalists who, for another gift, provide the required charm.

The charm is not disposed of after it has served its purpose, but is placed in the charmbox of the household shrine.  As these magical materials are specific for certain ills, and the real or imagined maladies of the people are many, the charm-box is usually full to overflowing.  The magical packets are so numerous that people forget what their purposes were and fear to use them again.  While the natives are very vague on this point, we can only assume that the idea in retaining all the old magical materials is that their presence in the charm-box, before which the body rituals are conducted, will in some way protect the worshiper.

Beneath the charm-box is a small font.  Each day every member of the family, in succession, enters the shrine room, bows his head before the charm-box, mingles different sorts of holy water in the font, and proceeds with a brief rite of ablution.  The holy waters are secured from the Water Temple of the community, where the priests conduct elaborate ceremonies to make the liquid ritually pure.

So the ivory pendant might be jewelry, or might have served some other unknown purpose.  Almost 42 millennia later, it's a little difficult to be certain.

Be that as it may, it's an amazing find.  And if it is jewelry, it shows this drive for adornment goes back a long way.  Myself, I've never been a big jewelry-wearer; mostly I just wear my wedding ring.  As far as clothing goes, I have a fashion sense that frequently makes my wife wonder if I know how to use an iron, or possibly even look in a mirror.  I make up for it, however, with some large and complex tattoos, which I've written about here before (the linked post has pics, if you're curious).  So I guess I'm no stranger to the decorative urge myself.

In any case, it's mind-boggling to think about what life must have been like back then, squarely in the middle of the Last Glacial Period, when the people in central Europe co-existed with mammoths, woolly rhinoceros, and cave lions.  Despite the harshness of the climate and the dangers of running afoul of one of these big critters, they took the time to carve up and decorate mammoth ivory -- which shows that whatever the purpose, they weren't so different from us today.

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It's astonishing to see what the universe looks like on scales different from those we're used to.  The images of galaxies and quasars and (more recently) black holes are nothing short of awe-inspiring.  However, the microscopic realm is equally breathtaking -- which you'll find out as soon as you open the new book Micro Life: Miracles of the Microscopic World.

Assembled by a team at DK Publishers and the Smithsonian Institution, Micro Life is a compendium of photographs and artwork depicting the world of the very small, from single-celled organisms to individual fungus spores to nerve cells to the facets of a butterfly's eye.  Leafing through it generates a sense of wonder at the complexity of the microscopic, and its incredible beauty.  If you are a biology enthusiast -- or are looking for a gift for a friend who is -- this lovely book is a sure-fire winner.  You'll never look the same way at dust, pollen, algae, and a myriad of other things from the natural world that you thought you knew.

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

Frames of Reference

For this week's Fiction Friday: a short story I wrote a while back about not judging a book by its cover, even if the cover is kind of ugly.

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The day Tommy Schallenberger met the orc started out normally enough. 

It was during the soft midsection of summer vacation, some indeterminate date in the middle of July, the time when twelve-year-old boys ignore even the day of the week into non-existence. It was long enough after the end of school that the frantic desperation to cling to every moment had passed, and not yet near enough to the beginning of the next school year that a new, and altogether different kind, of frantic desperation had begun.

Tommy was splashing his way down the creek bed, clad only in a disreputable pair of cargo shorts, his brown hair streaked with sun-faded gold and his shoulders and cheeks bronzed and freckled. There was nothing purposeful about what he was doing. If an adventure presented itself, that was fine. If not, he could pass an agreeable afternoon doing nothing but exploring the creek and trying to catch frogs.

He jumped down from a flat rock by a shallow waterfall onto a projecting shelf lower down, and almost lost his footing, but with that preternatural grace that some pre-adolescent boys have, he regained his balance after teetering for a moment on the ball of one foot. There was a rustle in the bushes, off to the side and downstream, but Tommy paid it little heed. Deer were common and unafraid, and if it wasn’t a deer, the other possibilities didn’t seem all that alarming. The last black bear seen near Tommy’s house had been ten years ago, and for a boy who had been raised on Bear in the Big Blue House, even that thought seemed more intriguing than frightening.

Tommy jumped from the shelf down to the lower creek bed, where the water recommenced flowing after bubbling for a bit in an oval pool. He miscalculated the depth of the pool, however, and found himself suddenly immersed up to the waist in remarkably cold water. Reflexively, he tried to scramble out, and his natural sense of balance failed him. His bare feet slipped on the algae-coated surface of the rock, and arms flailing, he fell over backwards.

Tommy was a good swimmer, and the water wasn’t that deep. so there was never any real danger. But he inhaled a big gulp of water, and came up gagging and coughing, and as a result slipped again and went back under. And that was when a strong hand grabbed him by the wrist, and lifted him bodily out of the pool, to hang there like a caught fish, dripping and sneezing and spitting out creek water.

Tommy looked at his rescuer. A shriek rose from his gut, got caught halfway, and came out as a thin whine.

A thick-set, broad body, arms far too long and legs too short to seem human, was surmounted by a nearly spherical head of such amazing ugliness that Tommy immediately wondered if he’d drowned in the pool and been summarily sent to hell. The eyes were small and piglike, the hair scanty but coarse. The ears were long and pointed, and stuck out from the side of its head like wings. Like Tommy it was only clad from the waist down, and its skin was a rather alarming gray-green. The creature’s mouth was impossibly wide, and pulled into either a grimace or a smile—it was hard to tell which it was. 

Tommy coughed again, and tried to yell for help, but his vocal chords were still in open rebellion, and it came out as a faint “Eeep.”

[Image of an orc has been released by the artist, Mathias Panzenböck, into the Public Domain]

“If that was an attempt to call for help,” the creature said, in a remarkably cultured voice, “what the hell do you think I’m currently giving you?”

“What are you?” Tommy said, finally mastering his own voice enough at least to form words.

“What do I look like, a garden gnome?” the creature said, the irritation clear in its voice. “I’m an orc.”

“Orcs aren’t real.” Tommy tried to make his voice sound braver than he felt.

“Oh, yeah?” The orc swung Tommy effortlessly up onto dry land, and set him down. “Tell that to my parents, siblings, cousins, and so forth.”

“There are more of you?” Tommy massaged his shoulder.

The orc rolled its eyes. “Kid, do you know where babies come from?”

Tommy scowled and drew himself up, trying to look taller than his five-foot-two. “Of course I do.”

It shrugged. “Well, then?”

“Yeah, okay,” Tommy admitted. He looked more closely at the creature. “You’re not planning on killing me and eating me, are you?”

The orc sighed. “You humans and your propaganda. Why would I have rescued you if that was my plan? Wouldn’t it be easier to let you drown, and then eat you afterwards? Why rescue you, and then chase around a live boy and try to kill him?”

Tommy looked defiant. “Maybe you just like to make your victims suffer.”

The orc made a little “pfft” sound. “Bloody nonsense."

“Well, in The Lord of the Rings…” Tommy began.

“Oh, don’t get me started. Tolkien kind of sucked as a historian, frankly.”

Tommy goggled. “The Lord of the Rings is history?”

The orc regarded him for a moment, raising one eyebrow. “You think he made all that stuff up? Like, invented languages and so on? Get real.”

Tommy stared at the orc, tried to think of something to say in response, and failed completely.

“Well, of course,” the orc said, his voice thoughtful, “history is written by the victors, and all that sort of thing. It’s not like he was exactly biased to present us orcs in a positive light.”

“He said you liked to kill humans and elves and dwarves just for fun.”

“Yeah, like the dwarves and elves were innocent.” The orc's voice sounded bitter. “You know what happened when the dwarves got back to Moria? From the way Tolkien talked, the dwarves were helpless victims. What a crock. You know what the first thing they did was? Just guess.”

“Killed some orcs?” Tommy ventured.

“Of course!” shouted the orc. “What else? It was all, ‘Khazad-dûm belongs to the dwarves!’ in spite of the fact that they hadn’t lived there for hundreds of years, and they proceeded to run up toward a few orcs who were in the entry hall, and chop them into dog food. I ask you, does this sound fair?”

“Not really,” Tommy admitted. “But look. Some of the orcs did bad things. Like the ones that captured Merry and Pippin. And that big ugly dude who shot the arrows into Boromir.”

“Fair enough. There are orcs that aren’t very nice. Are all humans nice?”

“I guess not.”

“So, if I wrote a book, and picked out a few—Adolf Hitler, let’s say, and Stalin, and Genghis Khan, and so as not to appear sexist, Marjorie Taylor Greene—and used that to argue that humanity was the filthy spawn of mud and evil, you’d think that was unfair, wouldn’t you?”

“I suppose.”

“You know what that’s called? That’s called an overgeneralization. Do you know what an overgeneralization is?”

“I do now,” Tommy said.

“You know, I sometimes wonder if human schools ever teach critical thinking.” The orc paused. “Anyhow. Tolkien took the orcs that sided with Sauron and Saruman, and decided from them that all of the orcs were evil. Hardly fair, I’d call it. All of these other orcs, ordinary orcs, are at home minding their business, raising their kids, and just wanting to be left alone, and along comes Tolkien and basically says that the only good orc is a dead orc.” He paused, and looked a little sad. “No wonder there’s so few of us left.”

“I never thought of it that way.”

“It never occurred to you to ask the question of how an entire species could be evil?”

“Well, no,” Tommy admitted. “But now that I’ve met you, I can see that I should probably think more about it.”

“You’re not just saying that because you’re scared I’ll eat you?”

Tommy’s brown eyes met the orc’s small gray ones. “I’m not scared of you any more.”

The orc gave Tommy a speculative look. “You seem like you’re all right, kid. What’s your name?”

“Tommy. Tommy Schallenberger.” 

“Mine’s Globnorg.” The orc reached out a huge, rough hand, and briefly engulfed Tommy’s small one.

“Globnorg?” Tommy asked incredulously.

Globnorg scowled. “Yeah, that’s another thing. Tolkien made it sound like just because our language doesn’t sound as nice as Elvish, that means we’re the bad guys.”

“Well, you have to admit it doesn’t sound very pretty.”

“Huh.” Globnorg snorted. “Ever listen to German? It’s not exactly the language of love.”

Tommy didn’t say anything. His grandparents spoke German, mostly when they didn’t want him to understand what they were saying, and he had to admit they always sounded like they were arguing, even when they probably weren’t.

“Listen,” Globnorg said. “Elvish may sound all soft and silky, but that doesn’t mean much. I can tell you that their arrows aren’t soft and silky, they’re hard and pointy, and some of those Elves are serious badasses.”

“Legolas sure seemed to be, in the movie.”

“Legolas.” Globnorg gave a dismissive gesture with one huge, craggy hand. “Since when do Hollywood and reality have to be the same? Upper-class privileged pretty-boy rich kid snot, that’s what Legolas was. So far as I’ve heard, anyway. I never met him, though, it was a long time ago.”

“You’ve seen the movie?”

“Of course. We may be orcs, but we’re not backwards. We’ve got culture. But we’re smart about it. We’ve borrowed the nice things from you humans—movie streaming, computers, microwave ovens, cellphones. We avoided the traffic jams, nine-to-five jobs, and spam emails. And we’re not screwing up the environment like you humans, either. I just finished installing solar panels in front of my cave.”

“That’s cool,” Tommy said. His science teacher from fifth grade, Mrs. Wilkinson, had been very much in favor of solar panels, and he’d thought Mrs. Wilkinson was awesome. Anyone who agreed with Mrs. Wilkinson couldn’t be all bad.

“All it amounts to,” Globnorg said, “is your frame of reference. If all you hear all the time is orcs are bad, orcs are evil, orcs will kill you, then every little thing you hear about us afterwards—every time some misguided orc teenager knocks over a convenience store—it becomes evidence to support what you’d already decided is true. It’s another critical thinking thing—this one’s called confirmation bias. Ever heard of that?”

“I have now,” Tommy said again.

“Well, good. So you read Tolkien’s slanted, biased take on our culture, and you make your mind up, and after that everything that happens just makes your opinion set deeper into cement. That’s why you expected me to eat you.”

“Well…” Tommy paused. “There’s also the way you look.”

The orc grinned, exposing way more teeth than Tommy thought possible. “Judging by appearances. You’re a veritable textbook of logical fallacies, you are.”

“That one, I knew about already,” Tommy said meekly. “Sorry about that.”

“No harm done.” The orc shrugged. “It’s not like it doesn’t happen all the time. Anyhow, I’ve used up enough of your afternoon, talking philosophy. You probably want to get back to whatever you were doing.”

“I wasn’t doing anything,” Tommy said. “I was just walking.”

“Nothing wrong with that. Actually, that’s something my people could have used some reminding about, way back in the day. When did they get in trouble? When they let Sauron and Saruman talk them into these type-A personality Great Big Important Plans, and somehow convinced them that just being wasn’t enough, that they had to somehow Do Something Grand. Look what happened. Lot of good that did us, in the long run.”

“I guess that’s true.”

“Anyhow, Tommy, nice to meet you. Oh, and one quick request—you may not want to mention to your family about meeting me here. Not meaning to cast aspersions on your relatives, but these things have been known to end badly. Packs of dogs, people with torches, shotguns, and so forth. Ugly on all sides.”

“Don’t worry,” Tommy said. “I don’t think they’d believe me, anyhow.”

“Oh, okay, well, then. That’s all right.”

Tommy turned and walked a few feet away, then turned and looked back at Globnorg, half expecting that he’d be gone. He wasn’t. He raised one lumpy gray hand, and wiggled his fingers briefly in farewell. Tommy waved back.

“Watch your step on the rocks,” the orc shouted at him. “They’re slippery.” And just as he passed out of earshot, Tommy heard the orc say to himself, “Humans. Actually, they’re kind of cute when they’re little. In an ugly sort of way.”

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It's astonishing to see what the universe looks like on scales different from those we're used to.  The images of galaxies and quasars and (more recently) black holes are nothing short of awe-inspiring.  However, the microscopic realm is equally breathtaking -- which you'll find out as soon as you open the new book Micro Life: Miracles of the Microscopic World.

Assembled by a team at DK Publishers and the Smithsonian Institution, Micro Life is a compendium of photographs and artwork depicting the world of the very small, from single-celled organisms to individual fungus spores to nerve cells to the facets of a butterfly's eye.  Leafing through it generates a sense of wonder at the complexity of the microscopic, and its incredible beauty.  If you are a biology enthusiast -- or are looking for a gift for a friend who is -- this lovely book is a sure-fire winner.  You'll never look the same way at dust, pollen, algae, and a myriad of other things from the natural world that you thought you knew.

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

The moth and the flower

Ever heard of an evolutionary arms race?

It's a twist on coevolution, where the adaptations in one species affect the selection -- and therefore the evolution -- of another, unrelated species.  In arms races, as the name implies, it's specifically about biological weaponry, either for predation or for self-defense.  Finding lunch, or avoiding being lunch.  The most commonly-cited example of an arms race is speed and maneuverability in the cheetah and the impala.  The fastest cheetahs take down and eat the slowest impalas; the fastest impalas escape, and the slowest cheetahs starve.  (That's an oversimplification, but it'll do for now.)  The upshot is that over time, both the cheetah and the impala evolve the ability to run faster.  The most common outcome of arms races is that it continues until one of the species kind of maxes out on how far it can take the adaptation.  The cheetah might well be at that point; it's hard to imagine how they could be any faster without the strain on the joints, tendons, and muscles causing serious injury.

The odd thing about an arms race, though, is that sometimes it can backfire on one of the participants.  A relationship like this was the subject of a paper last week in the journal Alpine Entomology, which looked at a beautiful -- but highly poisonous -- plant, the alpine rose.

The alpine rose isn't a rose at all; it's a species of rhododendron (Rhododendron ferrugineum) that lives in a habitat not much else can tolerate.  It thrives only in rocky, acidic soils, just above the tree line in the Alps, Jura, Pyrenees, and Apennines.  Besides the obvious difficulties of living in a cold, windswept place, there's the issue that in such barren areas, any animals are going to find survival as tough as the plants do, so the local herbivores are going to eat pretty much anything green.  The alpine rose has responded by evolving a nasty cocktail of toxins, including the glycoside arbutin and the alkaloid arecoline, so even the hungriest of plant-eaters leave it alone.

[Image licensed under the Creative Commons MurielBendel, Rhododendron ferrugineum Valais4, CC BY-SA 4.0]

Well, most plant-eaters.  The current paper is about the discovery of a population of moths that have evolved to specialize on this plant.  It's the danger of an arms race; if one of the participants can exploit the adaptations of the other, it can actually end up better off.  Here, the moth has evolved tolerance to the alpine rose's toxins, and the result is it has a food source essentially to itself, with no competition.

The more the researchers looked into it, the more interesting the story got.  Not only had these moths evolved to specialize on eating alpine rose leaves, upon undergoing genetic analysis, they were shown to be conspecific with the species Lyonetia ledi, the Ledum leaf-miner moth.  This is a widespread species of moth that feeds mostly on the leaves of Labrador tea (Ledum palustre) and bog myrtle (Myrica gale).  This, however, left two puzzles: (1) most Ledum leaf-miners won't eat alpine rose; and (2) the nearest population of Ledum leaf-miners is over four hundred kilometers away.

What seems to have happened is that the moth, which feeds on plants that live in boggy areas at high altitude, was once more common -- during the last glacial period, when the favorable habitat was pretty much everywhere in Europe that wasn't actually covered in ice.  Then as things warmed up, the valleys became too warm for its host plants, and the range of both the plants and the moths moved upward in altitude, and broke up into patches.  One of them got isolated in the mountains of western Europe, where the alpine rose was way more common than either of the usual host plants for the species.  This created enormous selective pressure; as soon as there were moths that could at least tolerate the alpine rose's toxins, they were at such an advantage that they outcompeted their cousins and more or less took over.  Over time, this preference for alpine rose became a requirement.  Now, the moth feeds only on alpine rose -- something no other insect species can manage.

So that's today's cool science story; a poisonous flower and a relict population of moths stranded in the high mountains after the last glaciation.  Once again illustrating what Darwin meant by saying that evolution had created "many forms most beautiful and most wonderful" -- some of which are still out there waiting to be discovered.

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

It's astonishing to see what the universe looks like on scales different from those we're used to.  The images of galaxies and quasars and (more recently) black holes are nothing short of awe-inspiring.  However, the microscopic realm is equally breathtaking -- which you'll find out as soon as you open the new book Micro Life: Miracles of the Microscopic World.

Assembled by a team at DK Publishers and the Smithsonian Institution, Micro Life is a compendium of photographs and artwork depicting the world of the very small, from single-celled organisms to individual fungus spores to nerve cells to the facets of a butterfly's eye.  Leafing through it generates a sense of wonder at the complexity of the microscopic, and its incredible beauty.  If you are a biology enthusiast -- or are looking for a gift for a friend who is -- this lovely book is a sure-fire winner.  You'll never look the same way at dust, pollen, algae, and a myriad of other things from the natural world that you thought you knew.

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

Strange replicators

New from the "Well, I See No Way This Could Go Wrong, Do You?" department, we have: some researchers who have built living things from stem cells that went on to discover how to reproduce themselves in a completely novel fashion.

A team of scientists at the University of Vermont, Tufts University, and Harvard University created what they call "xenobots" -- clusters of living stem cells taken from the African clawed frog (Xenopus laevis) that were on their way to becoming skin cells, but were excised and then arrayed in spherical clusters.  These clusters began to reproduce, creating new clusters.

"Well, so what?" you may be saying.  "Cells reproduce.  It's one of the characteristics of life.  What's so weird about that?"

What I haven't told you is that the clusters (1) reproduced not by mitosis, or at least not solely by mitosis -- they reproduced by scooping up loose cells in the petri dish and assembling them into new clusters; and (2) when the scientists noticed that the original clusters usually died after reproducing, they turned a supercomputer on the problem of whether it was possible to adjust the shape of the cluster to make it better at reproducing and more likely to survive -- and the model worked.

"[W]ith an artificial intelligence program working on the Deep Green supercomputer cluster at UVM's Vermont Advanced Computing Core, an evolutionary algorithm was able to test billions of body shapes in simulation -- triangles, squares, pyramids, starfish -- to find ones that allowed the cells to be more effective at the motion-based 'kinematic' replication reported in the new research," said Sam Kriegman, lead author on the paper, which appeared in Proceedings of the National Academy of Sciences this week.  "We asked the supercomputer at UVM to figure out how to adjust the shape of the initial parents, and the AI came up with some strange designs after months of chugging away, including one that resembled Pac-Man.  It's very non-intuitive.  It looks very simple, but it's not something a human engineer would come up with.  Why one tiny mouth?  Why not five?  We sent the results to Doug [Blackiston, of Tufts University] and he built these Pac-Man-shaped parent xenobots.  Then those parents built children, who built grandchildren, who built great-grandchildren, who built great-great-grandchildren."

One of the xenobots picking up a smaller cluster of cells

The scientists say they named them "xenobots" because of the genus name of the frog species they were created from -- Xenopus -- but I don't think it's a coincidence that the root word of both, the Greek word ξενος, means "strange."

"This is profound," said study co-author Michael Levin.  "These cells have the genome of a frog, but, freed from becoming tadpoles, they use their collective intelligence, a plasticity, to do something astounding.... We were stunned that these biological objects -- a computer-designed collection of cells -- will spontaneously replicate.  We have the full, unaltered frog genome, but it gave no hint that these cells can work together on this new task, of gathering and then compressing separated cells into working self-copies."

The whole thing unfortunately brought to mind an episode of the highly scientific documentary series Kolchak: The Night Stalker called "Primal Scream," wherein some scientists brought back tissue samples from a drill site in the Arctic.  The samples, which looked like (and probably were) a tin can full of Silly Putty, were kept in cold storage until one day the cooling system failed.  This somehow spurred the tissue to spontaneously grow into a creature that looked like the love child of Ron Perlman and Sasquatch, which of course went on a rampage and killed lots of people.

Kolchak eventually figures out that being a cave man (as it were), it would try to find caves to hide in.  Despite (1) being from the Arctic, and (2) being frozen for millions of years, the creature apparently knew all about the geography of Chicago, and figured out that there were tunnels underneath a sports stadium where it could live.  Kolchak followed it there, and after some tense moments where he bumbled around in his usual fashion, dropping his camera, gun, flashlight, hat, etc., he was able to kill the creature and save the day.

But I digress.

The researchers, for their part, don't seem worried about their creation getting loose and causing problems.  "These millimeter-sized living machines, entirely contained in a laboratory, easily extinguished, and vetted by federal, state and institutional ethics experts, are not what keep me awake at night," said study co-author Joshua Bongard.  "This is an ideal system in which to study self-replicating systems.  We have a moral imperative to understand the conditions under which we can control it, direct it, douse it, exaggerate it."

Because we've never seen movies before where the scientist says, "Stand back!  I know how to control the monster!" and promptly gets messily devoured.

In all seriousness, this does once again turn the spotlight on how we define "life."  The xenobots aren't that near the edge of the definition; they are, after all, made from living cells, not from off-the-shelf chemicals.  But given our ability to synthesize biological compounds (including DNA) pretty much to order, it may not be much longer before we see a truly artificial life-form -- something that shares no common ancestry with terrestrial life at all, and is entirely created in a laboratory.  Couple that with the last few years' awe-inspiring work in artificial intelligence, and we are truly looking at the fulfillment of the line Shakespeare gave to Miranda in The Tempest: "O, brave new world, that has such people in it!"

Even if those "people" are currently little blobs of cells, you have to wonder how long they're going to stay that way.

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

It's astonishing to see what the universe looks like on scales different from those we're used to.  The images of galaxies and quasars and (more recently) black holes are nothing short of awe-inspiring.  However, the microscopic realm is equally breathtaking -- which you'll find out as soon as you open the new book Micro Life: Miracles of the Microscopic World.

Assembled by a team at DK Publishers and the Smithsonian Institution, Micro Life is a compendium of photographs and artwork depicting the world of the very small, from single-celled organisms to individual fungus spores to nerve cells to the facets of a butterfly's eye.  Leafing through it generates a sense of wonder at the complexity of the microscopic, and its incredible beauty.  If you are a biology enthusiast -- or are looking for a gift for a friend who is -- this lovely book is a sure-fire winner.  You'll never look the same way at dust, pollen, algae, and a myriad of other things from the natural world that you thought you knew.

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

The law of small numbers

A few days ago, I had a perfectly dreadful day.

The events varied from the truly tragic (receiving news that a former student had died) to the bad but mundane (losing a ghostwriting job I'd been asked to do because the person I was working for turned out to be a lunatic, and had decided I was part of a conspiracy against him -- the irony of which has not escaped me) to the "I'll-probably-laugh-about-this-later-but-right-now-I'm-not" (my dog, Guinness, recovering from his recent illness, and feeling chipper enough to swipe and destroy my wife's favorite hat) to the completely banal (my computer demanding an operating system update when I was in the middle of working, tying it up for two and a half hours).

All of this brought to mind the idea of streaks of bad (or good) luck -- something that you find people so completely convinced of that it's nearly impossible to get them to break their conviction that it sometimes happens.  We've all had days when everything seems to go wrong -- when we have what my dad used to call "the reverse Midas touch -- everything you touch turns to shit."  There are also, regrettably fewer, days when we seem to have inordinate good fortune.  My question of the day is: is there something to this?

Of course, regular readers of this blog are already anticipating that I'll answer "no."  There are actually three reasons to discount this phenomenon.  Two have already been the subjects of previous blog posts, so I'll only mention them in brief.

One is the fact that the human brain is wired to detect patterns.  We tend to take whatever we perceive and try to fit it into an understandable whole.  So when several things go wrong in a row -- even when, as with my experiences last week, they are entirely unrelated occurrences -- we try to make them into a pattern.

The second is confirmation bias -- the tendency of humans to use insignificant pieces of evidence to support what we already believe to be true, and to ignore much bigger pieces of evidence to the contrary.  I had four bad things, of varying degrees of unpleasantness, occur one day last week.  By mid-day I had already decided, "this is going to be a bad day."  So any further events -- the computer update, for example -- only reinforced my assessment that "this day is going to suck."  Good things -- like the fact that even though our dog is back to getting into trouble, he is recovering; like the the fact that we've been enjoying the International Ceramics Congress workshops this weekend; like the fact that lovely wife brought me a glass of red wine after dinner -- get submerged under the unshakable conviction that the day was a lost cause.

It's the third one I want to consider more carefully.

I call it the Law of Small Numbers.  Simply put: in any sufficiently small data sample, you will find anomalous, and completely meaningless, patterns.

To take a simple model: let's consider flipping a fair coin.  You would expect that if you flip said coin 1000 times, you will find somewhere near 500 heads and 500 tails. On the other hand, what if you look at any particular run of, say, six flips?

[Image licensed under the Creative Commons ICMA Photos, Coin Toss (3635981474), CC BY-SA 2.0]

In any six-flip run, the statisticians tell us, all possible combinations are equally likely; a pattern of HTTHTH has exactly the same likelihood of showing up as does HHHHHH -- namely, 1/64.  The problem is that the second looks like a pattern, and the first doesn't.  And so if the second sequence is the one that actually emerges, we become progressively more amazed as head after head turns up -- because somehow, it doesn't fit our concept of the way statistics should work.  In reality, if the second pattern amazes us, the first should as well -- when the fifth coin comes up tails, we should be shouting, "omigod, this is so weird" -- but of course, the human mind doesn't work that way, so it's only the second run that seems odd.

Another thing is that in the second case, the six-flip run of all heads, when it come to the seventh flip, what will it be?  It's hard for people to shake the conviction that after six heads, the seventh is bound to be tails, or at least that tails is more likely.  In fact, the seventh flip has exactly the same likelihood of turning up heads as all the others -- 1/2.

All of this brings up how surprisingly hard it is for statisticians to model true randomness.  If a sequence of numbers (for example) is actually random, all possible combinations of two numbers, three numbers, four numbers, and so on should be equally likely.  So, if you have a truly random list of (say) ten million one-digit numbers, there is a possibility that somewhere on that list there are ten zeroes in a row.  It would look like a meaningful pattern -- but it isn't.

This is part of what makes it hard to create truly randomized multiple-choice tests.  As a former science teacher, I frequently gave my classes multiple-choice quizzes, and I tried to make sure that the correct answers were placed fairly randomly.  But apparently, there's a tendency for test writers to stick the correct answer in the middle of the list -- thus the high school student's rule of thumb, which is, "if you don't know the answer, guess 'c'."

Randomness, it would seem, is harder to detect (and create) than most people think.  And given our tendency to see patterns where there are none, we should be hesitant to decide that the stars are against us on certain days.  In fact, we should expect days where there are strings of bad (or unusually good) occurrences.  It's bound to happen.  It's just that we notice it when several bad things happen on the same day, and don't tend to notice when they're spread out, because that, somehow, "seems more random" -- when, in reality, both distributions are random.

I keep telling myself that.  But it is hard to quell what my mind keeps responding -- "thank heaven it's a new week - it's bound to be better than last week was."

Well, maybe.  I do agree with another thing my dad used to tell me: "I'd rather be an optimist who is wrong than a pessimist who is right."  I'm just hoping that the statisticians don't show up and burst my bubble.

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

It's astonishing to see what the universe looks like on scales different from those we're used to.  The images of galaxies and quasars and (more recently) black holes are nothing short of awe-inspiring.  However, the microscopic realm is equally breathtaking -- which you'll find out as soon as you open the new book Micro Life: Miracles of the Microscopic World.

Assembled by a team at DK Publishers and the Smithsonian Institution, Micro Life is a compendium of photographs and artwork depicting the world of the very small, from single-celled organisms to individual fungus spores to nerve cells to the facets of a butterfly's eye.  Leafing through it generates a sense of wonder at the complexity of the microscopic, and its incredible beauty.  If you are a biology enthusiast -- or are looking for a gift for a friend who is -- this lovely book is a sure-fire winner.  You'll never look the same way at dust, pollen, algae, and a myriad of other things from the natural world that you thought you knew.

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

Vikings, auroras, and tree rings

The idea that people from Europe came to North America (long) before Columbus has not only generated interest amongst legitimate archaeological and historical researchers, it has generated a lot of nonsense.

One nonsensical bit is that the Mandan tribe not only descends from Welsh explorers (including quasi-mythical personages such as Prince Madog), but that they have blue eyes and their language is a dialect of Welsh.  None of this is even remotely true, but the story (which had dropped into well-deserved obscurity) regained currency with Madeleine L'Engle's novel A Swiftly Tilting Planet.  While I have to admit it's a decent story in other respects, the whole thing about Native Americans having blue eyes -- and worse, that blue eyes = good and brown eyes = bad -- is seriously cringe-inducing.  In any case, the Mandans themselves live in what is now North and South Dakota, which last I looked is nowhere near the Atlantic Ocean, so the claim is pretty ridiculous anyhow.

Other accounts describe encounters with Welsh-speaking Monacans of Virginia and Tuscarora of New York.  There is no evidence, linguistic or otherwise, supporting those claims.  The brilliant historian of Welsh history Gwyn Williams summed up such stories as "a complete farrago [that] may have been intended as a hoax."

Then there's the Irish story of St. Brendan the Navigator, who supposedly crossed the Atlantic in a coracle with a group of monks, and which is shakier ground still.  The Brendan legend is so wound up in mythology and religious miracle stories that it's impossible to tell what, if anything, about it is true.  Even the Brendan enthusiasts don't agree on much.  "Brendan's Fair Isle," where the monks supposedly landed after defeating various sea monsters and demons, has been identified as coastal North America -- and also the Faeroes, the Azores, Madeira, and the Canary Islands.

There's no hard evidence of any of it.

More reliable -- and corroborated by actual science -- is the claim that the Vikings landed in northeastern North America in the late tenth and early eleventh century, founding colonies in what they called Vinland -- meaning either "land of grape vines" or "meadow-land," depending on which linguist you believe.  The Skraelings ("wearers of animal skins"), as they called the Natives they encountered, were described as unequivocally hostile.  (Funny how surprised the colonizers always seem to be when indigenous people resent someone walking in and saying, "Get out of the way, this is my home now.")  In any case, the whole enterprise is outlined in Eirík the Red's Saga, in which the eponymous Eirík, his son Leif Eiríksson, and their friend Thorfinn Karlsefni lead repeated expeditions between the Icelandic settlements in Greenland and the new ones in Vinland, and which is usually considered to be at least substantially true.

The whole topic was brought to my attention once again because of my sharp-eyed friend Gil Miller, who knowing my fascination with all things Scandinavian sent me a link to an article in SciTech Daily describing new research into the archaeological evidence at L'Anse aux Meadows, Newfoundland.  L'Anse aux Meadows is the one and only certain settlement site by Europeans in North America prior to Columbus, and the current research -- using a clever twist on tree-ring analysis -- determined that the site was occupied in the year 1021, exactly a thousand years ago.

A recreation of the Scandinavian settlement at L'Anse aux Meadows [image licensed under the Creative Commons Dylan Kereluk from White Rock, Canada, Authentic Viking recreation, CC BY 2.0]

Between the sagas and the artifacts uncovered at L'Anse aux Meadows, the site seems to have flourished between the years 970 and 1030 C.E.  The problem is, trying to pin down the exact years of occupation of an abandoned settlement is not an easy task.  The key to the new study is an event that occurred in late 992 and early 993 (as verified by dendrochronological evidence from elsewhere, as well as historical records).  Apparently there was a huge solar storm that lasted at least a couple of months.  Historians from the era report vivid auroras that were visible way farther south than usual, and the tree rings show a sudden increase in the uptake of carbon-14, a form of carbon created by cosmic rays striking the upper atmosphere.  The researchers took samples of wood that were cut by the Scandinavian colonists at L'Anse aux Meadows, and after identifying the high C-14 rings in the wood -- corresponding to 993 C. E. -- they were able to determine that the wood had been cut from the living tree in the year 1021.

The research, which appeared in Nature last month, was led by Margot Kuitems of the University of Groningen.  The authors write:

Our result of AD 1021 for the cutting year constitutes the only secure calendar date for the presence of Europeans across the Atlantic before the voyages of Columbus.  Moreover, the fact that our results, on three different trees, converge on the same year is notable and unexpected.  This coincidence strongly suggests Norse activity at L’Anse aux Meadows in AD 1021...  This date offers a secure juncture for late Viking chronology.  More importantly, it acts as a new point-of-reference for European cognisance of the Americas, and the earliest known year by which human migration had encircled the planet.  In addition, our research demonstrates the potential of the AD 993 anomaly in atmospheric 14C concentrations for pinpointing the ages of past migrations and cultural interactions.  Together with other cosmic-ray events, this distinctive feature will allow for the exact dating of many other archaeological and environmental contexts.

It's always amazing to me when we can bring the tools of science to bear on historical or quasi-mythological claims.  The most famous one, of course, is Heinrich Schliemann's discovery of the city of Troy, supporting that The Iliad (minus the interference by various gods and goddesses, and possibly the involvement of a giant wooden horse) had its basis in a real war that led to the sack and burning of the city.  But here, we have far more conclusive evidence of a more recent event -- the arrival of Vikings in North America -- and are now able to state with confidence when it happened. 

Which is way more exciting that any spurious claims of blue-eyed, Welsh-speaking Natives.

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

It's astonishing to see what the universe looks like on scales different from those we're used to.  The images of galaxies and quasars and (more recently) black holes are nothing short of awe-inspiring.  However, the microscopic realm is equally breathtaking -- which you'll find out as soon as you open the new book Micro Life: Miracles of the Microscopic World.

Assembled by a team at DK Publishers and the Smithsonian Institution, Micro Life is a compendium of photographs and artwork depicting the world of the very small, from single-celled organisms to individual fungus spores to nerve cells to the facets of a butterfly's eye.  Leafing through it generates a sense of wonder at the complexity of the microscopic, and its incredible beauty.  If you are a biology enthusiast -- or are looking for a gift for a friend who is -- this lovely book is a sure-fire winner.  You'll never look the same way at dust, pollen, algae, and a myriad of other things from the natural world that you thought you knew.

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