Our ancient Roman would simply wipe him- or herself, rinse the tersorium in whatever was available (running water and/or a bucket of vinegar or salt water), and leave it for the next person to use.Photograph by Kapustin Igor / Shutterstock
We’ve all been caught unawares by our digestive tract at one time or another.
It happened to the Nash family several months ago. We were nearing the end of an extended road trip, driving down a secondary highway through a sparsely populated area of Colorado at night, when one of my 9-year-old twin sons had to use the bathroom. Despite my pleading, he said he couldn’t make it to the next town. (He had to poop.) So we pulled over and headed for the bushes. After he took care of his business, we realized that we didn’t have toilet paper with us.
The whole dramatic episode got me thinking, and for the next couple of hours, I pondered toilet paper and the cultural nature of bathroom routines. (Cut me some slack. It was a long drive.)
Toilet paper is now such a routine part of our lives that we rarely give it any thought. That boring reality, however, should make us… Read More…
It’s not just in politics where otherwise smart people consistently talk past one another. People debating whether humans have free will also have this tendency. Neuroscientist and free-will skeptic Sam Harris has dueled philosopher and free-will defender Daniel Dennett for years and once invited him onto his podcast with the express purpose of finally having a meeting of minds. Whoosh! They flew right past each other yet again.
Christian List, a philosopher at the London School of Economics who specializes in how humans make decisions, has a new book, Why Free Will Is Real, that tries to bridge the gap. List is one of a youngish generation of thinkers, such as cosmologist Sean Carroll and philosopher Jenann Ismael, who dissolve the old dichotomies on free will and think that a nuanced reading of physics poses no contradiction for it.
List accepts the skeptics’ definition of free will as a genuine openness to our decisions, and he agrees this seems to be at odds with the clockwork universe of fundamental physics and neurobiology. But he argues that fundamental physics and neurobiology are only part of the story of human behavior. You may be a big bunch of atoms governed by the… Read More…
Georg Cantor died in
1918 in a sanatorium in Halle, Germany. A pre-eminent mathematician, he had
laid the foundation for the theory of infinite numbers in the 1870s. At the
time, his ideas received hostile opposition from prominent mathematicians in
Europe, chief among them Leopold Kronecker, once Cantor’s teacher. In his first
known bout of depression, Cantor wrote 52 letters to the Swedish mathematician
Gösta Mittag-Leffler, each of which mentioned Kronecker.
But it was not just
rejection by Kronecker that pushed Cantor to depression; it was his inability
to prove a particular mathematical conjecture he formulated in 1878, and was
convinced was true, called the Continuum Hypothesis. But if he blamed himself,
he did so needlessly. The debate over the conjecture is profoundly uncertain:
in 1940 Kurt Gödel proved that the Continuum Hypothesis cannot be disproven (technically speaking, that the negation of the Hypothesis cannot be proven),
and in 1963 Paul Cohen proved that it cannot be proven. Poor Cantor had chosen
quite the mast to lash himself to.
In his first known bout of depression, Cantor wrote 52 letters to the Swedish mathematician Gösta Mittag-Leffler, each of which mentioned Kronecker.
How is it possible,
though, for something to be provably… Read More…
What is sex for? When I regularly queried students at the beginning of my course in evolutionary biology, most responded that it was for reproducing. Reasonable enough, but wrong. In fact, lots of living things reproduce without sex: Asexual reproduction is found not only in many forms of archaea and bacteria, but also in numerous plants and protists, as well as in fully one half of all animal phyla.
Baker’s yeast reproduce by budding, as do hydra and parasites such as tapeworms. Other creatures, including fungi and some algae, make spores without sex. Some reproduce when pieces of themselves generate new individuals—that is, by fragmentation—as among planarians and a number of annelid worms and marine oligochaetes. Then there is parthenogenesis, literally from the Greek partheno (virgin) plus genesis (creation). Such virgin birthing is the norm among water fleas and rotifers. It has been found in at least two species of sharks (hammerheads and blacktips), and is regularly employed by New Mexico whiptail lizards and occasionally by boa constrictors, although it has not—yet—been reported for any birds or mammals. (Or humans, except for one supposed instance.)
VIRGIN BIRTH: Blacktip sharks are known to give birth through parthenogenesis. A baby shark is conceived… Read More…
The word lox was one of the clues that eventually led linguists to discover who the Proto-Indo-Europeans were, and where they lived.Photograph by Helen Cook / Flickr
One of my favorite words is lox,” says Gregory Guy, a professor of linguistics at New York University. There is hardly a more quintessential New York food than a lox bagel—a century-old popular appetizing store, Russ & Daughters, calls it “The Classic.” But Guy, who has lived in the city for the past 17 years, is passionate about lox for a different reason. “The pronunciation in the Proto-Indo-European was probably ‘lox,’ and that’s exactly how it is pronounced in modern English,” he says. “Then, it meant salmon, and now it specifically means ‘smoked salmon.’ It’s really cool that that word hasn’t changed its pronunciation at all in 8,000 years and still refers to a particular fish.”
How scholars have traced the word’s pronunciation over thousands of years is also really cool. The story goes back to Thomas Young, also known as “The Last Person Who Knew Everything.” The 18th-century British polymath came up with the wave theory of light, first described astigmatism, and played a key role in deciphering the Rosetta Stone. Like… Read More…
Nautilus by Raymond Coppinger & Lorna Coppinger - 1w ago
What is a dog? Many people often think of dogs as kennel club creations. The purebred dog is man’s best friend, not the street dog. Man’s best friends live ubiquitously in the United States, Europe, and other developed countries and, in these countries, are by and large household pets. Man’s best friends only live in areas where people have easy access to vaccines against rabies and distemper. They are the results of certain levels of commercial appeal involving pet stores, breeders, dog food companies, veterinary medicine, magazines, and books.
But could it be that breeds represented as working, hunting, or pet groups don’t represent real dogs? Could it be that the so-called stray dogs, street dogs, neighborhood dogs, village dogs, and even feral dogs of the world are the real, naturally evolved, self-selected dogs?
When watching the dogs in the Mexico City dump, a number of our students would say, “These dogs are different from real dogs—these are mongrels.” The implication is that the kennel club breeds are the ancestors of the village dogs. People seem to believe that if a dog doesn’t look like one of the kennel club recognized breeds then it must be a hybrid… Read More…
The rat sat still in the middle of her cage, moving only in response to my touch, and even then only as if in slow-motion. My subject, GRat66, was a few months old, and except for her long bare tail, fit neatly into my palm a few minutes earlier, when I injected a few drops of a potent opiate under her skin, near the belly. Now, her beady black eyes bulged as she faded into an opiate stupor.
I was preparing to implant minuscule electrodes into the rat’s brain. The opiate would serve as an analgesic before, during, and after the surgery. It was the fall of 2018 and I was hoping the results of the surgery would help answer some questions that had been tormenting me as I embarked on the sixth year of my Ph.D. in neuroscience. How do the parts of the brain controlling movement interact with those responsible for visual sensation? Why do neurons in the visual areas jolt to action when an animal moves, even in the dark?
I placed GRat66 into an anesthesia-induction chamber, a small plastic box connected to a vaporizer that dispenses the anesthetic, isoflurane. After she was sufficiently knocked out (I… Read More…
As they often do after a rainstorm, butterflies had gathered around puddles on Pigeon Mountain in northwest Georgia. Nets in hand, James Adams and his friend Irving Finkelstein watched the insects lapping up salts and proteins dissolved in the muddy water, their folded wings yawning apart now and then. There were silvery-blue Celastrinas and Skippers the color of cinnamon and ash. Largest of all were the Tiger Swallowtails—pastel lemon males with black dagger-like stripes and midnight-dark females with a dusting of evening cerulean.
Suddenly a very odd creature flitted past Adams and Finkelstein—a swallowtail unlike any they had ever seen. Its left half was yellow; its right, black. It was as though someone had sliced up two different insects and seamlessly sewn them back together. Finkelstein yelped and took a swipe at the bizarre beauty, missing by quite a bit. Suppressing his excitement, lest it misguide his hand, Adams chased the butterfly a few steps, swung, and netted it. He could see immediately that he had caught a gynandromorph—an animal that was half-male and half-female.
Butterfly collectors love gynandromorphs for their rarity as much as their peculiarity. They are unpredictable hiccups in nature’s symphony of symmetry. The creatures… Read More…
Reprinted with permission from Quanta Magazine’s Abstractions blog.
A strange glow coming from the Milky Way’s center was thought to be due to ordinary pulsars. But a new look at a years-old study shows that dark matter might still be responsible.NASA/JPL-Caltech
The galactic center shines too brightly, like the glow of a metropolis at night where maps show only a town. To mend their cosmic cartography, astrophysicists have spent years debating what could be powering this excess of energetic light. In 2015 the arguments appeared to swing decisively in favor of a somewhat prosaic explanation—that a large population of dim neutron stars was responsible. But a new examination of that work, posted on the scientific preprint site arxiv.org earlier this month, revealed a likely flaw in those analyses. “There’s something happening in the data we don’t understand,” said Rebecca Leane, a theoretical physicist at the Massachusetts Institute of Technology and co-author of the paper.
The new study, along with two others that came out in March, reopens the possibility that space-based instruments have found the first direct evidence of the elusive “dark matter” thought to pervade the universe.
What the hyper-rational Vulcan Spock represents, psychologist Igor Grossman said, is “uniform emotional down-regulation,” whereas the hallmark of Yoda’s judgment style is his ability to “recognize and balance a wide range of emotions”—a key aspect of wisdom.Star Wars / YouTube
This past “Star Wars Day,” May 4, I watched some of the original trilogy a bit mournfully: Peter Mayhew, who played Chewbacca, passed away the day before. When The Empire Strikes Back took us to the Yoda-dwelling Dagobah, I recalled what the exiled Jedi Master had told premonition-plagued Anakin Skywalker decades earlier, about how to deal with the fear of losing loved ones. “Death is a natural part of life,” he tells Anakin. “Rejoice for those around you who transform into the Force. Mourn them do not. Miss them do not. Attachment leads to jealousy—the shadow of greed, that is.”
Yoda is often held up as an avatar or icon of sagacity. Take a recent example. The psychologist Igor Grossman, who heads the Wisdom and Culture Lab at the University of Waterloo, published a study in January with colleagues on the role of emotion in reasoning wisely. In their study—which involved observational, diary, and experimental methods and almost 4,000 participants—the… Read More…