What Makes A Tree A Tree?

By Rachel Ehrenberg, Knowable Magazine | April 16, 2018 3:06 pm
(Credit: Cristina Gottardi/Unsplash)

(Credit: Cristina Gottardi/Unsplash)

Several years ago, after Thanksgiving dinner at my parents’ house in Vermont, lightning struck a backyard maple tree. There was a ferocious crack and the darkness outside the kitchen windows briefly turned day-bright. It wasn’t until spring that we knew for certain the tree was dead.

This maple was a youngster, its trunk the diameter of a salad plate. Were its life not cut short by catastrophe, the tree might have lived 300 years. But death by disaster is surprisingly common in trees. Sometimes it results from a tragic human blunder, as with the 3,500-year-old Florida bald cypress that was killed in 2012 by an intentionally lit fire. More often, calamity strikes via extreme weather — drought, wind, fire or ice. Of course, trees also are susceptible to pests and disease; adversaries like wood-decaying fungi can significantly shorten a tree’s life. But the ones that manage to evade such foes can live for an incredibly long time. Read More

CATEGORIZED UNDER: Living World
MORE ABOUT: plants

Drugs from Bugs: Bioprospecting Insects to Fight Superbugs

By Troy Farah | April 13, 2018 12:05 pm
(Credit: Yusnizam Yusof/Shutterstock)

(Credit: Yusnizam Yusof/Shutterstock)

Somewhat like looking down the barrel of a gun, antibiotic resistance is a looming threat to modern medicine. The rise of MRSA, super drug-resistant gonorrhea and other “nightmare” bacteria risk rendering our microscopic defenses useless. What to do when your last-last-last resort fails to kill these pathogens?

Someday, perhaps sooner than later, we’re going to need new antibiotics, not to mention medicines for cancer, depression, and other conditions that aren’t readily treatable by current prescriptions. So, how do we find new pharmaceuticals? Read More

CATEGORIZED UNDER: Health & Medicine, Top Posts
MORE ABOUT: vaccines & drugs

Our Ancestors Got High, Too

By Cody Cottier | April 9, 2018 8:00 am
high-drug-ancestor

Humans have been getting high for a long, long time. (Credit: Shutterstock)

The tales we tell — from Homer and Genesis to your friend’s ninth recounting of that epic rave last summer — are rich with drug use. But studies show our ancestors were chewing, brewing and blazing long before they started to record their intoxicated escapades.

Virtually all human societies use mind-altering substances. What’s more, about 90 percent give drug-induced altered states of consciousness a role in their fundamental belief systems, according to a survey of 488 modern societies. And this isn’t new. Many psychoactive plants we consume today, and those that have fallen out of style, date back thousands of years.

A Psychoactive Sampling

Before we made drugs a societal menace, we respected them and used them for healing and spiritual purposes. Psychoactive plants fell under the jurisdiction of shamans, and some scholars believe early religion is rooted in their prophetic hallucinations, though this has been contested. Others wonder whether drugs played a part in the origins of symbolic life and major intellectual breakthroughs.

Use of Peyote, a desert cactus with natural hallucinogens, dates back as far as 5,700 years. It was so indispensable that some Native American groups traveled days or weeks each year to harvest a year’s worth of the holy cactus in the Chihuahuan desert of Mexico and Texas.

peyote-drug-hallucinogen

Peyote, a small spineless cactus, has been getting people high for thousands of years. (Credit: Shutterstock)

In “Fingerprints of God: The Search for the Science of Spirituality,” religion correspondent Barbara Hagerty described a peyote ceremony: everyone “sat cross-legged on the floor, motionless, gazing at the flames with sleepy eyes dilated by the mescaline from the sacred herb peyote. Three strapping young men with long black hair moved around the circle, pounding on a water drum and singing an urgent chant.”

Other drugs have an even longer history. In the same region, another hallucinogen called the mescal bean, which was used in a similar way to peyote, has been found in caves and rock shelters extending back to 9,000 years ago. In Peru, the oldest remains of the psychoactive San Pedro cactus date to 6,800-6,200 B.C.

More familiar today is opium —its descendants are heroin and morphine — and it was equally renowned in the antiquity of the Old World. It produces euphoria, pain relief and drowsiness, and it seems to be the most widespread of the ancient drugs, reaching most of Europe by the sixth millennium B.C. Poppy capsules adorn many Eastern Mediterranean artifacts, like figurines and jewelry, highlighting opium’s range of symbolic meanings.

poppy-goddess-opium-drug-high

A figurine of the Poppy Goddess from Gazi, 1300-1200 B.C. (Credit: Pecold/Shutterstock)

In the South American Andes, coca is the drug of choice, and has perhaps been so for 8,000 years. Chewing the leaves of this plant, from which we now derive cocaine, helps to stave off fatigue, hunger, thirst and altitude sickness. Many indigenous tribes also use it in ritual contexts.

Smoking pipes in Argentina have been dated to as early as 2,100 B.C., and chemical analysis suggests they were used either to smoke tobacco or other hallucinogenic plants. As for marijuana, Neolithic Chinese farmers were growing hemp for various reasons by the fifth millennium B.C., including as a hallucinogen.

And of course, we can’t forget shrooms. Prehistoric Homo sapiens were so enamored of the fantastic fungi that many formed sacred cults around them in Mesoamerica. Small sculptures of human figures crowned with umbrella-like mushrooms are common throughout the region, dating between 500 B.C. and 900 A.D. In Siberia, Finno-Ugrian tribes have likely been aware of fly agaric — the classic image of a magic mushroom, red with white speckles — since “time immemorial.”

mushroom-stones-drug-shrooms

These mushroom stones were found at highland Mayan sites in Guatemala and are from around 500 B.C. Once thought as phallic stones, they’re now widely accepted as being associated with a mushroom cult. (Credit: Dr. Stephan F. de Borhegyi, 1961)

Origins of Craving

One of the oldest potential cases of medicinal drug use involves a 60,000-year-old Neanderthal. Around his burial site lay various plants, including the stimulant ephedra. Some have disputed this evidence, as the grave also contained the bones of a gerbil-like rodent that may have hauled in the plants itself.

Some wild animals have been observed to act inebriated after eating overly ripe fruit, and this points to one theory of the human-alcohol dynamic. It’s — magnificently — titled the “Drunken Monkey Hypothesis,” and it may account for our intoxication impulse.

Before they hunted for meat, our primate forebears foraged for fruit. The hypothesis suggests a strong desire for the smell and taste of alcohol, produced in fruit as yeast converts its sugars into ethanol, would help them to detect dinner at peak ripeness.

In that evolutionary vein, some researchers speculate that mammals and psychoactive plants each influenced the development of the other over millions of years. They note that we have adapted to metabolize the plants, while their defense chemicals have evolved to replicate and disrupt the function of our neurotransmitters, implying a “deep time” relationship.

Intentional fermentation likely came after humans began using psychoactive plants, many of which are consumed raw. One of the first confirmed alcoholic beverages was a Chinese concoction of wild grapes, hawthorn fruit, rice and honey.

Considering that all staple cereals — like barley, wheat and maize — are fit for brewing, some have even suggested that humans may have domesticated these crops for beer rather than bread.

Wasn’t Always a War

Over the centuries humans learned to distill spirits and refine drugs like cocaine, heroin and methamphetamine. They experimented with snorting, injecting and inhaling their intense new creations. One theory of addiction is that psychoactive drugs weren’t as common or as addictive in our ancestral landscape, so we never evolved the internal control to resist them in high doses. Instead we relied on the limits of nature, and now we just aren’t wired to withstand their modern, purified abundance.

The increasing potency of drugs in an unrestricted environment has led to numerous epidemics throughout history, and today addiction is a global dilemma. As for the U.S., the opioid crisis in particular is growing more deadly each year.

More than 33,000 Americans died from opioid overdoses in 2015, and the next year about 64,000 died from drug overdoses in general. But the perception of drugs as a public enemy, and the push to eradicate them, seems to be a fairly new concept.

Elisa Guerra-Doce, a Spanish researcher, published a review of archaeological evidence for psychoactive drugs in prehistory. She and many others argue that despite contemporary problems, drugs have traditionally served socially constructive purposes. By examining the way humans have used them for millennia, we may gain a better understanding of how to benefit from them without the harm.

“Considering the failures of the war on drugs,” Guerra-Doce writes, “perhaps our modern societies should look into the past and learn something from ‘the primitive.’”

CATEGORIZED UNDER: Mind & Brain, Top Posts

Don’t Blame Me, Blame My Brain Implant

brain-implant

Probes that can transmit electricity inside the skull raise questions about personal autonomy and responsibility. (Credit: Hellerhoff, CC BY-SA)

Mr. B loves Johnny Cash, except when he doesn’t. Mr. X has watched his doctors morph into Italian chefs right before his eyes.

The link between the two? Both Mr. B and Mr. X received deep brain stimulation (DBS), a procedure involving an implant that sends electric impulses to specific targets in the brain to alter neural activity. While brain implants aim to treat neural dysfunction, cases like these demonstrate that they may influence an individual’s perception of the world and behavior in undesired ways. Read More

CATEGORIZED UNDER: Technology, Top Posts
MORE ABOUT: medical technology

How to Discover New Cloud Species

By Graeme Marlton, University of Reading | March 27, 2018 1:09 pm
File 20180321 165580 1mj5vws.jpg?ixlib=rb 1.1

Asperitas cloud over Newtonia, Missouri, US. (Credit: © Elaine Patrick, Cloud Appreciation Society Member 31940)

Clouds form in a multitude of different shapes and sizes, their infinite combinations and position across the sky offering a visual drama in response to the light conditions. But despite their apparent randomness, a detailed naming convention is in place to categorize them.

When a cloud ultimately can’t be fitted into one of the many existing categories, it can be nominated for a classification of its own. In 2017, the World Meteorological Organisation (WMO) added 12 new types of cloud to the International Cloud Atlas, the world standard guide for cloud classification. And I worked as part of a small team investigating the science behind one newly categorized cloud, Asperitas, which exhibits wave-like perturbations, reminiscent of a rough sea in the base of the cloud. Read More

CATEGORIZED UNDER: Environment, Top Posts

Should We Worry About Computer Algorithms’ ‘Mental Health’?

By Thomas T. Hills | March 26, 2018 11:12 am
computuer-AI

(Credit: Shutterstock)

Is my car hallucinating? Is the algorithm that runs the police surveillance system in my city paranoid? Marvin the android in Douglas Adams’s Hitchhikers Guide to the Galaxy had a pain in all the diodes down his left-hand side. Is that how my toaster feels?

This all sounds ludicrous until we realize that our algorithms are increasingly being made in our own image. As we’ve learned more about our own brains, we’ve enlisted that knowledge to create algorithmic versions of ourselves. These algorithms control the speeds of driverless cars, identify targets for autonomous military drones, compute our susceptibility to commercial and political advertising, find our soulmates in online dating services, and evaluate our insurance and credit risks. Algorithms are becoming the near-sentient backdrop of our lives. Read More

CATEGORIZED UNDER: Technology, Top Posts

From Marie Curie to the Demon Core: When Radiation Kills

By Sarah Watts | March 23, 2018 10:04 am
Cherenkov radiation glowing in the core of the Advanced Test Reactor at Idaho National Laboratory. (Credit: Argonne National Laboratory)

Cherenkov radiation glowing in the core of the Advanced Test Reactor at Idaho National Laboratory. (Credit: Argonne National Laboratory)

When we hear the word “radiation,” we tend to think of atomic bombs (like the ones that fell on Hiroshima and Nagasaki), or environmental mishaps like the three-eyed fish living outside Springfield’s nuclear power plant on The Simpsons. But radiation – a term that refers to the transmission of energy through waves and particles – is not always a destructive force.

“The word radiation is a lot broader than people realize,” says Johnathan M. Links, a medical physicist and professor at Johns Hopkins School of Public Health. “When people say radiation, what they usually mean is ionizing radiation, which has sufficient energy to eject electrons from atoms. Non-ionizing radiation doesn’t have that capability, and that’s an important distinction. When you eject electrons from atoms you can break chemical bonds, and that’s what leads to the microscopic and macroscopic damage that radiation causes.” Read More

Let’s Journey Through the Mind of a Dog

By Erica Tennenhouse | March 22, 2018 12:55 pm
an adorable dog looking at the camera

(Credit: Shutterstock)

Inside a dog’s furry head are millions of neurons firing away, passing chemicals to one another and generating thoughts. We may guess at what our canine pals are thinking about: food, a walk, their loving owners.

But for all the time humans spend interacting with dogs, their thoughts largely elude us, and it’s easy to see why: dogs can’t speak their minds (at least in any language we know). But we still are curious about our best bud’s mindset, and scientists have devised creative methods to get into their heads. While our grasp of canine cognition may never approach what we know of the human psyche, the latest research has yielded tantalizing nuggets about the inner lives of dogs. Read More

CATEGORIZED UNDER: Living World, Mind & Brain, Top Posts

Theoretically, Recording Dreams Is Possible…Scientists Are Trying

By Charlotte Hu | March 21, 2018 1:44 pm
(Credit: Shutterstock)

(Credit: FCSCAFEINE/Shutterstock)

Dreams can feel awfully real when you’re deep in sleep. Perhaps you find a hidden doorway in your home that leads to entirely new rooms and passageways. Maybe you went to work in your underwear—yikes.

When you wake up, you check your closet for that mysterious doorway; maybe you jolt awake in a cold sweat, instantly relieved you still have plenty of time to properly clothe yourself before leaving the house. Regardless, whatever you were experiencing felt very real just moments ago.

Dreams are essentially vivid memories that never existed. Yet you find yourself inside an all-encompassing parallel reality, a fantastical world that’s uniquely yours. The trouble with dreams, especially the fun ones, is that they’re fleeting. Often, you can’t remember a thing from a dream just moments after waking—the echo of some feeling is all that remains. But what if you could record your dreams, and play them back for analysis, or even share them with friends?

Theoretically, experts say, that might one day be possible. Read More

CATEGORIZED UNDER: Mind & Brain, Top Posts

Hold Off Dyeing Your Hair With Graphene Nanoparticles

By Andrew Maynard, Arizona State University | March 20, 2018 3:56 pm
graphene-nanoparticle-hair-dye

Subbing new risks for the current dyes’ dangers? (Credit: Evgeny Savchenko/Shutterstock)

Graphene is something of a celebrity in the world of nanoscale materials. Isolated in 2004 by Nobel Prize winners Andre Geim and Konstantin Novoselov, these ultrathin sheets of carbon atoms are already finding novel uses in areas like electronics, high-efficiency heating systems, water purification technologies and even golf balls. According to recent research published in the journal Chem, hair dyes can now be added to this list.

But how safe and responsible is this new use of the carbon-based wonder-material?

Northwestern University’s press release proudly announced, “Graphene finds new application as nontoxic, anti-static hair dye.” The announcement spawned headlines like “Enough with the toxic hair dyes. We could use graphene instead,” and “’Miracle material’ graphene used to create the ultimate hair dye.” Read More

CATEGORIZED UNDER: Technology, Top Posts
MORE ABOUT: materials science
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