Category: Living World

How Tree Rings Solved a Musical Mystery

By Stephen E. Nash | May 3, 2017 10:15 am
tree-rings

Dendrochronologist Henri Grissino-Mayer and colleagues study the tree rings in the Karr-Koussevitzky double bass. Their analysis ultimately determined that the instrument was built much later than previously thought. (Credit: Henri Grissino-Mayer)

Modern science is full of surprising analytical techniques that can be used in a wide variety of remarkable circumstances.

My favorite technique is dendrochronology—the study of “tree time.” By assigning calendar-year dates to growth rings in trees, scientists can garner information relevant to an astonishing range of disciplines, including archaeology, climatology, the study of fire history, and many others. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: plants

Why Felines Can’t Resist the #CatSquare

By Nicholas Dodman, Tufts University | April 18, 2017 12:40 pm
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Next best thing to a hidey-hole box? (Credit: Maggie Villiger, CC BY-ND)

Twitter’s been on fire with people amazed by cats that seem compelled to park themselves in squares of tape marked out on the floor. These felines appear powerless to resist the call of the #CatSquare. The Conversation

This social media fascination is a variation on a question I heard over and over as a panelist on Animal Planet’s “America’s Cutest Pets” series. I was asked to watch video after video of cats climbing into cardboard boxes, suitcases, sinks, plastic storage bins, cupboards and even wide-necked flower vases.

“That’s so cute … but why do you think she does that?” was always the question. It was as if each climbing or squeezing incident had a completely different explanation.

It did not. It’s just a fact of life that cats like to squeeze into small spaces where they feel much safer and more secure. Instead of being exposed to the clamor and possible danger of wide open spaces, cats prefer to huddle in smaller, more clearly delineated areas.

Kittens get securely snuggled by their mothers. (Credit: Shutterstock)

When young, they used to snuggle with their mom and litter mates, feeling the warmth and soothing contact. Think of it as a kind of swaddling behavior. The close contact with the box’s interior, we believe, releases endorphins – nature’s own morphine-like substances – causing pleasure and reducing stress.

Along with Temple Grandin, I researched the comforting effect of “lateral side pressure.” We found that the drug naltrexone, which counteracts endorphins, reversed the soporific effect of gentle squeezing of pigs. Hugs, anyone?

Also remember that cats make nests – small, discrete areas where mother cats give birth and provide sanctuary for their kittens. Note that no behavior is entirely unique to any one particular sex, be they neutered or not. Small spaces are in cats’ behavioral repertoire and are generally good (except for the cat carrier, of course, which has negative connotations – like car rides or a visit to the vet).

One variation on this theme occurs when the box is so shallow that it does not provide all the creature comforts it might.

Or then again, the box may have no walls at all but simply be a representation of a box – say a taped-in square on the ground. This virtual box is not as good as the real thing but is at least a representation of what might be – if only there was a real square box to nestle in.

This virtual box may provide some misplaced sense of security and psychosomatic comfort.

The cats-in-boxes issue was put to the test by Dutch researchers who gave shelter cats boxes as retreats. According to the study, cats with boxes adapted to their new environment more quickly compared to a control group without boxes: The conclusion was that the cats with boxes were less stressed because they had a cardboard hidey-hole to hunker down in.

Availability of a cozy box is part of a well-appointed space for a cat. (Credit: Lisa Norwood, CC BY-NC)

Let this be a lesson to all cat people – cats need boxes or other vessels for environmental enrichment purposes. Hidey-holes in elevated locations are even better: Being high up provides security and a birds’s-eye view of the world, so to speak.

Without a real box, a square on the ground may be the next best thing for a cat, though it’s a poor substitute for the real thing. Whether a shoe box, shopping bag or a square on the ground, it probably gives a cat a sense of security that open space just can’t provide.

Nicholas Dodman, Professor Emeritus of Behavioral Pharmacology and Animal Behavior, Cummings School of Veterinary Medicine, Tufts University

 

This article was originally published on The Conversation. Read the original article.

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: animals

Genomics Is Buried in Too Much Data

By Patrick Chain | April 10, 2017 12:26 pm
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(Credit: Alix Kreil/Shutterstock)

When a sore throat and sinus congestion warrant a visit to the doctor, your physician will attempt to determine whether a cold virus or bacterial infection is to blame—oftentimes without success. So, just to be safe, they might write a potentially unnecessary script for an antibiotic.

But what if a nurse could swipe your saliva and run a quick genetic test for bacteria? If the test results are negative, you get a prescription for a decongestant and orders to get some rest, rather than contributing to the widespread overuse of antibiotics. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: genetics

Get Lost in Mega-Tunnels Dug by South American Megafauna

By Andrew Jenner | March 28, 2017 1:39 pm
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Looking into a large paleoburrow in Brazil. (Courtesy: Heinrich Frank)

It was in 2010 that Amilcar Adamy first investigated rumors of an impressive cave in southern Brazil.

A geologist with the Brazilian Geological Survey (known by its Portuguese acronym, CPRM) Adamy was at the time working on a general survey of the Amazonian state of Rondonia. After asking around, he eventually found his way to a gaping hole on a wooded slope a few miles north of the Bolivian border.

Unable to contact the landowner, Adamy couldn’t study the cave in detail during that first encounter. But a preliminary inspection revealed it wasn’t the work of any natural geological process. He’d been in other caves nearby, formed by water within the same geology underlying this particular hillside. Those caves looked nothing like this large, round passage with a smooth floor.

“I’d never seen anything like it before,” said Adamy, who resolved to return for a closer look some day. “It really grabbed my attention. It didn’t look natural.”

Read More

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MORE ABOUT: paleontology

Phosphorus Is Vital for Life, and We’re Running Low

By Vera Thoss, Bangor University | March 15, 2017 11:05 am
phosphorus

A farmer sprays field with a nitrogen, phosphorus, potassium fertilizer. (Credit: oticki/Shutterstock)

All life needs phosphorus and agricultural yields are improved when phosphorus is added to growing plants and the diet of livestock. Consequently, it is used globally as a fertilizer – and plays an important role in meeting the world’s food requirements.

In order for us to add it, however, we first need to extract it from a concentrated form – and the supply comes almost exclusively from phosphate mines in Morocco (with far smaller quantities coming from China, the US, Jordan and South Africa). Within Morocco, most of the mines are in Western Sahara, a former Spanish colony which was annexed by Morocco in 1975.

The fact that more than 70 percent of the global supply comes from this single location is problematic, especially as scientists are warning that we are approaching “peak phosphorus”, the point at which demand begins to outstrip supply and intensive agriculture cannot continue to provide current yields. In the worst case scenario, mineable reserves could be exhausted within as little as 35 years.

So what is going on – and how worried should be?

Here be phosphorus. (Credit: Shutterstock)

Natural Limits

In nature, phosphorus only exists bound to oxygen, which is called phosphate. It is in this form that it is mined. Chemists can remove the oxygens bound to it to get elemental white phosphorus, which glows in the dark, but it is so unstable that it spontaneously ignites on exposure to air.

Phosphate easily diffuses through soil or water and can be taken up by cells. When phosphate meets free calcium or iron, they combine to give highly insoluble salts.

In the first half of the 19th century, Justus von Liebig popularized the law of the minimum for agriculture, which states that growth is limited by the least available resource. It was soon discovered that this was often some form of phosphorus.

As a consequence, bones – comprised mostly of calcium and phosphate – from old battlefields were dug up to use in farming. Guano, large accumulations of bird droppings, also contains high concentrations of phosphorus and was used to fertilize crops. But supplies of this were soon depleted. As demand increased, supplies had to be mined instead.

But this applied inorganic phosphate fertilizer is highly mobile and leaches into watercourses. In addition, phosphate rock weathers and is also ultimately washed into the ocean where it either deposits as calcium phosphate or is taken up by marine organisms who also eventually deposit on the ocean floor when they die. Consequently, terrestrial phosphorus doesn’t really disappear, but it can move beyond our reach.

Natural Wastage

To complicate matters further, even the phosphorus we can use is largely wasted. Of the phosphorus mined as fertilizer, only a fifth reaches the food we eat. Some leaches away and some is bound to calcium and iron in the soil. Some plant roots have the ability to extract the latter, but not in large enough quantities to retrieve all of it.

In addition to these inorganic forms, phosphate is also converted into cellular compounds, creating organically-bound phosphorus, such as phospholipids or phytate. After the death of an organism, these organic phosphorus compounds need to be returned into the useable phosphate form. How much organically-bound phosphorus is present in soils depends on the number and activity of the organisms that can do this.

Phosphorous boosts crop yields. (Credit: Shutterstock)

Agricultural soils are usually rich in inorganic phosphorus while in undisturbed ecosystems, such as forests and long-term pastures, organically-bound phosphorus dominates. But agricultural land is often depleted of phosphorus during harvest and land management practices such as ploughing, hence the addition of phosphate-containing fertilizers.

Spreading manure and avoiding tillage are ways of increasing microbial abundance in the soil – and so keeping more phosphorus in an organically-bound form.

The risks of peak phosphorus can be countered with some simple solutions. Eating less meat is a start as huge amounts are used to rear livestock for meat. The chances are that agricultural yields are limited by phosphorus availability and will be further stretched as the global population grows.

Humans are themselves wasteful of phosphorus, as most of what we take in goes straight out again. Fortunately, technologies have been developed to mine phosphorus from sewage, but at present are too expensive to be practical.

Peak phosphorus does not mean that phosphorus will disappear, rather that the reserves with mineable high concentrations are depleting. Instead, we are increasing the background concentrations of phosphorus and adding it to the ocean floor. More sustainable phosphorus use requires a greater appreciation and understanding of the many organisms that make up soils – and the part they play in phosphorus distribution – or we may no longer be able to feed the world at an affordable price.

 

This article was originally published on The Conversation. Read the original article.

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: chemistry

The Frog Tongue’s Sticky Secrets Revealed

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(Credit: Shutterstock)

How does one get stuck studying frog tongues? Our study into the sticky, slimy world of frogs all began with a humorous video of a real African bullfrog lunging at fake insects in a mobile game. This frog was clearly an expert at gaming; the speed and accuracy of its tongue could rival the thumbs of texting teenagers. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: animals

The Underrated Genius of Neanderthals

By Stephen E. Nash | January 24, 2017 4:43 pm
caveman

Geico’s “so easy a caveman can do it” advertising campaign incorrectly minimized the intelligence of Neanderthals. (Credit: Shutterstock)

(This post originally appeared in the online anthropology magazine SAPIENS. Follow @SAPIENS_org on Twitter to discover more of their work.) 

For the last dozen years or so, Geico Insurance has run commercials featuring Neanderthals in modern contexts. The story line varies, but the take-home point does not: Switching to Geico is so easy that “even a caveman can do it,” says the tag line. The Neanderthal’s feelings are invariably hurt, and a stereotype gets perpetuated. Do Neanderthals really deserve such derision?

Popularly known as “cavemen,” Neanderthals were ancestral humans who lived in Western Europe, on the eastern shores of the Mediterranean, and in southwestern and central Asia from about 400,000 to 40,000 years ago. They lived in glacial environments during the Ice Age as well as in warmer time periods. Their foreheads were low and receding in contrast to the high, almost vertical foreheads of modern humans. They also had protruding faces and heavy brow ridges above their eyes. While it’s an open question whether you’d recognize a Neanderthal if you saw one on the street, groomed and dressed in modern clothes, I like to think they’d blend in at my museum’s holiday party. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: archaeology

Is Cloud Seeding Worth the Bet?

By Ian Graber-Stiehl | January 24, 2017 1:10 pm
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Pilots from Weather Modification, Inc., prepare the cloud seeding aircraft with seeding flares. (Credit: Derek Blestrud, Idaho Power Company)

“Make mud, not war.” That was the slogan of the American 54th Weather Reconnaissance Squad, the first military force to engage in weather warfare.

Throughout the Vietnam War, they flew 2,602 missions, releasing silver iodide, a compound that seeded clouds and exacerbated monsoons—or so the thinking went. Dubbed “Operation Popeye”, this rainy warfare would last from 1966-72, until banned under the 1977 Enmod Treaty on weather warfare. Popeye wasn’t the only attempt to weaponize seasonal events, but it was the most infamous. There was also, for example, an “exercise” aiming to make the Hồ Chí Minh trail muddier, named “Commando Lava”. The problem with infamy, however, is that the subjects of it rarely live up to the legend. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: earth science, weather

Pew! Pew! Paleontologists Harness the Power of Lasers

By Jon Tennant | December 20, 2016 12:38 pm

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When in possession of a priceless dinosaur skeleton, it’s always a good idea to fire a super-charged photon beam at it.

That’s Thomas G. Kaye’s philosophy: if you can fossilize it, you can fire a laser at it. Kaye, of the Foundation of Scientific Advancement, Sierra Vista, developed a laser-scanning technique that reveals stunning new details buried within dinosaur fossils — so meta. Now he’s traveling the world placing new specimens in his crosshairs.

Kaye is joined by Mike Pittman, who’s already infamous at Discover for spotting fossils while taking a whiz in the Gobi Desert. Together, they’re trekking around the world armed with nothing more than their portable laser and an inquisitive eye. Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: paleontology

A History Recalled, One Symbol at a Time

By Stephen E. Nash | December 7, 2016 11:46 am
Denver Museum of Nature & Science

The spiraling story of the Chief Martin White Horse Winter Count documents significant events in Lakota history each year from 1789 to 1910. (Credit: AC.7923/DMNS)

(This post originally appeared in the online anthropology magazine SAPIENS. Follow @SAPIENS_org on Twitter to discover more of their work.) 

Time. Astronomers, philosophers, physicists, anthropologists, politicians, geographers, and theologians have all pondered the nature and meaning of time. Is it linear or cyclical? Is it reversible? (Put another way, can we go back in time?) Is time absolute and measurable, as it seemed to be to Isaac Newton and Galileo Galilei, or is it relative, as Albert Einstein theorized? Cynically, is it “what keeps everything from happening at once,” as science fiction author Ray Cummings wrote so memorably in 1923? Is time a cultural construct? Or is it a corollary to the second law of thermodynamics, under which disorder always increases? Why does time seem to go so much faster the older we get? Read More

CATEGORIZED UNDER: Living World, Top Posts
MORE ABOUT: anthropology
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