Category: Living World

Fecal Feasts Bring Earwig Families Together

By Erica Tennenhouse | August 3, 2016 7:00 am
European earwig

A European earwig (Credit: InsectWorld/Shutterstock)

A steaming bowl of fresh feces isn’t a meal that will bring the family together over the holidays. But for many animals, fecal consumption is a way of life.

The technical term for eating poo is coprophagy, from the Greek kopros for “dung”, and phagein, “to eat”. Though we most commonly associate coprophagy with domestic dogs, many other animals are known to indulge.

Rabbits re-ingest their own droppings to extract extra nutrients; dung beetles have gone a step further and built a specialized diet around balls of manure; growth of American bullfrog tadpoles is enhanced by access to intestinal output; and consumption of fecal matter helps mediate the exchange of essential gut fauna in mice. Read More

CATEGORIZED UNDER: Living World, Top Posts

Lost or Found? A Stick Chart From the Marshall Islands

By Stephen E. Nash | July 29, 2016 2:07 pm
Chart, Navigational; Micronesian; Republic of the Marshall Islands; Oceania

It would be hard to guess, but this arrangement of bamboo sticks and cowrie shells makes up a map of the ocean and the greater Marshall Islands region. (Credit: A.926.1/DMNS)

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

In a recent blog post, I focused on the Global Positioning System (GPS) and mused on how we ever got along without high-tech navigational aids. GPS units became common in cars and phones only in the last 15 years or so.

I remember when a road trip required a stop at the local American Automobile Association office to gather free maps of the planned route. Likewise, I remember when well-traveled road warriors had at least one dog-eared copy of a Rand McNally Road Atlas in their cars. Those days are gone, and I miss them. Read More

CATEGORIZED UNDER: Living World, Top Posts

From Jet Fuel to Medicine, Tobacco Growers Turn a New Leaf

By David Warmflash | July 27, 2016 7:00 am
A tobacco farm in the southern United States.

(Credit: Raymond Gregory/Shutterstock)

It is notorious for its role in the expansion and continuation of American slavery, and for its adverse health effects. The latter includes cardiovascular disease and various cancers, including lung cancer, the most common malignancy, underlying millions of deaths each year.

Health officials, attorneys, and activists have spent decades targeting its industrial cultivators in an effort to limit its advertising and sale, particularly to minors. Read More

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

What We’re Learning from the World’s Oldest Calculator

By Mike Edmunds, Cardiff University | July 21, 2016 2:58 pm
Antikythera mechanism

The Antikythera mechanism (Credit: Wikimedia Commons)

When we talk of the history of computers, most of us will refer to the evolution of the modern digital desktop PC, charting the decades-long developments by the likes of Apple and Microsoft. What many don’t consider, however, is that computers have been around much longer. In fact, they date back millennia, to a time when they were analogue creations.

Today, the world’s oldest known “computer” is the Antikythera mechanism, a severely corroded bronze artifact which was found at the beginning of the 20th Century, in the remains of a shipwreck near the Mediterranean island of Antikythera. It wasn’t until the 1970s that the importance of the Antikythera mechanism was discovered, when radiography revealed that the device is in fact a complex mechanism of at least 30 gear wheels. Read More

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

Extinction Looms for Easter Island’s Only Remaining Native Species

By Nathaniel Scharping | July 19, 2016 12:58 pm
DSCN0357

Jut Wynne at Rano Kao Volcano conducting reconnaissance for the cliff work to take place in August. (Credit: Rafael Rodriguez Brizuela)

On Easter Island, isolated in the middle of the vast Pacific Ocean, ten species of near microscopic insects are all that remain of the island’s native species — at least for now.

Hidden in volcanic caves that dot the island, the endemic insects of Rapa Nui eke out an existence in an increasingly imperiled habitat. Their ancestral homes, fragile gardens of moss and ferns, are endangered by tourists flooding into the tiny island, and hordes of invasive species threaten to crowd them out. The island may have been immortalized by its iconic Moai, monolithic stone statues standing some 40 feet tall, but its most important inhabitants are almost too small to be seen. Read More

CATEGORIZED UNDER: Environment, Living World, Top Posts

Blame Your Subpar Fitness on That Neanderthal DNA

By Bridget Alex | July 13, 2016 11:26 am
Neanderthal-in-museum

A Neaderthal strikes a pose at the State Museum of Prehistory in Halle, Germany. (Credit: Bridget Alex)

Most of us harbor about 2 percent Neanderthal DNA, inherited when our ancestors bred with Neanderthals more than 50,000 years ago. This was revealed back in 2010, when geneticists salvaged enough fragments of ancient DNA from Neanderthal bones to piece together a full genome. The discovery squelched a longstanding debate over whether Neanderthals and modern humans met — they did — and mated — oh yeah.

But why do we only have 2 percent Neanderthal ancestry? And what are the effects of that Neanderthal DNA on living humans? And why did our ancestors survive and Neanderthals go extinct? We’ve attributed our supremacy to bigger brains, better diets and advanced technology, but there may be a subtler, less flattering explanation for our evolutionary success. Read More

CATEGORIZED UNDER: Living World, Top Posts

Could Goats or Cows Claim the Title of ‘Man’s Best Friend’?

By Catherine Douglas, Newcastle University | July 8, 2016 3:13 pm
goats-cows

(Credit: MustafaNC/Shutterstock)

Since the evolution of dogs from wolves tens of thousands of years ago, they have been selectively bred for various roles as guards, hunters, workers and companions. But dogs are not the only animal humans have domesticated, which suggests that although dogs get all the attention, there’s reason to argue other species could also deserve the title of “man’s best friend”.

Anthrozoology, the study of human-animal relationships, has established that dogs demonstrate complex communication with humans. Charles Darwin thought that dogs experienced love, but it was only in 2015 that Japanese scientists demonstrated what we all intuitively knew. Miho Nagasawa and colleagues sprayed the “love hormone” oxytocin up dogs’ noses, measured the loving gaze between dog and human, and then measured the oxytocin levels in the humans’ urine, finding them to be higher. Rest assured, dog owners, that science has verified your bond with your faithful hound. Read More

CATEGORIZED UNDER: Living World, Top Posts

The Chicken-hearted Origins of the ‘Pecking Order’

By Jack El-Hai | July 5, 2016 12:03 pm
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A chicken gives another a peck. (Credit: tryptophanatic/Shutterstock)

At the turn of the twentieth century, a young Thorleif Schjelderup-Ebbe began vacationing with his wealthy parents, both sculptors, at a country retreat outside Kristiania (now Oslo), Norway, where he immersed himself in the lives of birds in the barnyard.

He gave them names, closely watched how they behaved, and learned how to recognize one from the other. He “became terribly interested in chickens, terribly interested,” Schjelderup-Ebbe’s son Dag recounted in 1986 in an interview published in Human Ethology Bulletin. Read More

CATEGORIZED UNDER: Living World, Top Posts

Are We Loving Monarchs to Death?

By Susan Brackney | June 21, 2016 7:30 am
shutterstock_145672700

(Credit: Michael Warwick)

Until recently, monarchs have mostly been at Mother Nature’s mercy—contending with disease, weather fluctuations, and heavy predation in the wild.

Lately, however, the efforts of a well-meaning public to bring monarch eggs and larvae indoors to raise to maturity, or to purchase large numbers of farmed monarchs for release into the wild, may be making life even more difficult for the beleaguered butterfly. Experts suggest such activities expose monarchs to disease, interfere with its genetic diversity, and stymie scientists’ efforts to track its migration patterns. Sadly, this isn’t the first time our good intentions toward monarchs have gone bad.

Monarchs in Decline

“People know monarchs have been in trouble. Their numbers in Mexico have been low for the past several years,” says Sonia Altizer, director of Project Monarch Health and a professor at the Odum School of Ecology at the University of Georgia. Scientists have observed declines by as much as 97 percent of historic highs and 97 percent of long-term population averages.

According to Sarina Jepsen, director of Endangered Species and Aquatic Programs at The Xerces Society for Invertebrate Conservation, “There were highs of almost a billion monarchs—like 800 million monarchs. Currently, this last year, I think we had counted in Mexico either 120 or 150 million.”

To help boost monarch populations, more and more gardeners and armchair naturalists are removing monarch eggs and larvae from the reach of predators, raising them indoors and subsequently releasing the adult butterflies back into the wild. Still others purchase large numbers of captive-bred monarchs from commercial butterfly farms for release into the wild. Sounds helpful, right? Wrong.

“I know people who purchase monarchs and use them in outreach and education, but, if you’re buying them with the goal of, ‘I’m going to release them and supplement the population,’ there are a lot of problems with that,” says Altizer says.

chrysalises

(Credit: Susan Brackney)

Ongoing Debate

These practices troubled a group of leading entomologists and conservation biologists to such a degree that they set aside differences in opinion just long enough to issue a consensus statement against the release of purchased, mass-reared monarchs from butterfly farms. They also urged individuals rearing monarchs on their own to do so only while following safe rearing protocols and participating in citizen science programs such as the Monarch Larva Monitoring Project and Monarch Health.

Reaching that consensus wasn’t easy.

“There were some [conservationists] who thought people shouldn’t be rearing any [monarchs indoors.],” recalls Karen Oberhauser, a professor in the Department of Fisheries, Wildlife, and Conservation Biology at the University of Minnesota and director of the Monarch Larva Monitoring Project. “Well-meaning and smart people are going to disagree on a lot of things, and none of us has a monopoly on the truth.”

shutterstock_100246115

(Credit: Noradoa/Shutterstock)

Elizabeth Howard, director of Journey North, an ongoing citizen science study of wildlife migration, notes, “I would say [the statement] could have been even stronger…. It’s such a balancing act, because all of us recognize how important the experience of raising monarchs is from a public education standpoint … Where it gets complicated is when you get into the question of how many. How many is enough? It’s the mass rearing that really raises concern.”

‘Scientific Vandalism’

Most experts agree that mass monarch rearing—particularly via commercial butterfly farms—and mass butterfly releases (say for weddings, funerals, and other events) are nothing but trouble. On the topic of mass releases, famed lepidopterist Robert Michael Pyle writes, “When celebrants are misled into thinking that they are doing something ecologically acceptable, even positive, by tossing monarchs into the void at their events, they are in fact party to scientific vandalism; rather than acting ‘green,’ they are helping to undermine our ability to correctly interpret the response of wild monarchs to all the challenges they face.”

Hospice organizations across the U.S. have also adopted the practice. “The organization buys [farmed butterflies] and then they charge people to release them as part of their fundraiser. That’s why it’s becoming so embedded, because people are doing these annually now … they’re raising a lot of money,” says Howard.

“There is absolutely no educational message. In fact, if anything, there’s a disregard for what happens to the butterfly when everybody goes home,” she adds. For its part, the International Butterfly Breeder’s Association (IBBA) released its own statement in defense of mass butterfly releases.

On average, one dozen monarchs sell for about $100. A charity can then charge members of the public between $30 and $50 per butterfly, pocketing the difference. But the monarchs themselves may be paying a higher price.

Risky Business

Commercial butterfly farms are largely unregulated, and the quality and health of the butterflies they produce can vary widely.

“With some growers,” says Altizer, “every single one of their butterflies is heavily infected, and, with other growers, none are. I don’t want to point a blanket finger at all commercial growers, but, in general, the risk is there. We’ve found that at least half of the commercial growers that we’ve looked at have problems with disease.”

shutterstock_306413549

(Credit: smilesbevie/Shutterstock)

Overcrowded conditions and poor hygiene are often to blame for the spread of Ophryocystis elektroscirrha (OE), a harmful protozoan that can cause serious deformities in adult butterflies. Some affected adults may appear healthy but still spread OE to other butterflies and larvae through the release of OE spores. Whether raised in a commercial facility or by well-meaning amateurs, sick, captive-reared butterflies that are released into the wild can contaminate existing, wild monarch populations.

“One of the things that is not mentioned in [our] statement is that butterflies all fly to the same place for the winter. So, if ever you were to think of a bad situation for any sort of communicable disease, you have it right there.” says Howard.

“I think also, in terms of raising a few [monarchs] in your back yard, or many, many, many people raising a few, it’s a drop in the bucket,” she continues. “The growth in the population would only be linear in that way, whereas the risk of disease is exponential. So, in terms of a numbers game, for every monarch you’re releasing, you’re adding one to the pool, but you’re potentially introducing disease that will spread exponentially.”

Migratory Miscues

Butterflies reared indoors don’t always develop the proper physiology to migrate either. They are often slightly smaller than their wild counterparts—and wings that are just a millimeter or two shorter than average can spell disaster for a butterfly on its long flight to Mexico.

Natural environmental cues like decreased day length, more extreme day-night temperatures, and deteriorating milkweed quality cause monarchs to enter a pre-migratory state known as reproductive diapause.

“When they’re exposed to one or more of those combinations of cues, they’re more likely to enter that migratory physiological state where, instead of having developed reproductive organs and being ready to breed, their reproductive organs are actually underdeveloped … and, instead, their bodies are primed to just tank up on fat and nectar,” Altizer explains.

Instead, monarchs raised indoors may be exposed to consistently long periods of artificial lighting, constant temperatures (thanks to air conditioning), and only the choicest milkweed (thanks to the keepers feeding them) while in captivity—thereby removing the environmental cues essential for triggering that pre-migratory state.

What Really Helps

Despite the potential pitfalls, in some instances, researchers believe it is still appropriate for individuals to raise small numbers of monarchs indoors.

“As long as [people are] rearing [monarchs] carefully, it’s not going to hurt those individuals or the population, and, if they’re reporting their data to a citizen science project, it’s going to help us understand monarchs,” says Oberhauser.

Altizer agrees, “In my mind, it’s not cut-and-dried, black-and-white where I would say people should absolutely never rear monarchs … there are some people who go to great lengths to educate themselves about hygienic rearing practices and about monarch disease, and go to great lengths to keep the conditions as natural as possible.”

Not ready to commit to a citizen science project? You can still be part of the solution for monarchs by planting native milkweed as well as nectar-rich plants and donating to organizations dedicated to monarch preservation, such as the Monarch Butterfly Fund and The Xerces Society for Invertebrate Conservation.

 

CATEGORIZED UNDER: Living World, Top Posts

Where Are All the Prehistoric Women and Children?

By Stephen E. Nash | June 16, 2016 1:26 pm
Denver Museum of Nature & Science

The archaeological record tends to preserve stone tools rather than perishable remains, such as this split-twig figurine found in Dolores Cave, near Gunnison, Colorado. (Credit: DMNS/A1291.1)

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

Stone tools, like Acheulean hand axes, remain well-preserved for eons because they are stones first, tools second. Fired ceramics remain well-preserved for millennia because they are, in essence, human-made stone. Metal tools may, in some rare instances, endure for millennia, but their material hardness belies chemical fragility; most are not stable over the long term. Bone tools, like their metal counterparts, may remain well-preserved, but preservation is highly specific to local burial chemistry. Artifacts made of perishable plant and animal remains, such as clothing, shoes, nets, baskets, and many toys, are rarely well-preserved, and therefore not very well-understood. Read More

CATEGORIZED UNDER: Living World, Top Posts
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