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Lenka Sentenska via National Geographic
Lenka Sentenska via National Geographic

Male Black Widows Practice Cannibalism, Too

Lenka Sentenska via National Geographic
Lenka Sentenska via National Geographic

Black widow spiders, nature’s femmes fatales, have earned their name from a long-held belief that the females typically devour their male counterparts immediately after mating. But recent research has uncovered at least one species of the spider in which this less-than-romantic habit is reversed.

After studying different pairings of the spiders (making sure to keep them well-fed, in order to rule out hunger-driven cannibalism), a team at Mazaryk University in the Czech Republic has concluded that, within the Micaria socialbilis species, male spiders are actually much more likely to eat the females than to be eaten. Unlike the instances of female cannibalism, the M. socialbilis males most often eat the females after their first contact, before any mating has taken place. Older females are more likely to be eaten; in the study, the reverse sexual cannibalism saw a peak when summer generation males encountered older females from the spring generation. Among these older female spiders, even large body size or virginity—desirable traits that usually only whet a male spider’s sexual appetite—can’t save them from becoming a meal.

Despite the macabre subject matter and endless ammo for sexist jokes, the study is actually a breakthrough. Said researchers Lenka Sentenska and Stano Pekar in the journal Behavioral Ecology and Sociobiology, “Our study provides an insight into an unusual mating system, which differs significantly from the general model. Even males may choose their potential partners and apparently, in some cases, they can present their choice as extremely as females do by cannibalizing unpreferred mates."

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These Fake Flowers Could Help Scientists Study At-Risk Bees
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If you haven't heard, the world's bees are having a crisis. According to one recent study, bee populations in some areas have plummeted by 75 percent in a quarter of a century. Some countries have introduced legislation banning certain pesticides in response to the news, but solving the complicated problem will likely require much more research. In order to gather better data on bee behavior, one new media artist has developed a machine that can give scientists a bug's-eye view.

As Co.Design reports, Michael Candy's Synthetic Pollenizer is designed to blend into a bee's natural environment. Yellow circles bolted around the opening of the device imitate the petals on a flower. Tubes pump real nectar and pollen into the center of the fake flower, so when bees land on it to feed, they're collecting real reproductive materials they can spread to the next plant they visit.

Candy, who's based in Brisbane, Australia, originally conceived the apparatus as a way for scientists to track the pollinating behaviors of bees. The synthetic flower is outfitted with cameras and dyes, and with enough of them distributed in the wild, researchers could see which bees travel to certain places and how long they stay.

After his concept reached the final round of the Bio Art and Design awards in the Netherlands, Candy decided to create his own prototype with help from an urban beekeeper in Melbourne, Australia. The invention worked: Bees mistook it for real flora and carried pollen from it to their next destination. But to use it for tracking and studying bees on a larger scale, Candy would need to build a lot more of them. The pollinators would also need to be scattered throughout the bees' natural habitats, and since they would each come equipped with a camera, privacy (for nearby residents, not the bees) could become a concern.

Even if the concept never gets the funding it needs to expand, Candy says it could still be used in smaller applications. Fake flowers designed to look like real orchids, for example, could encourage the pollination of endangered orchid species. But for people studying dwindling bee populations, orchids are low on the list of concerns: 30 percent of all the world's crops are pollinated by bees [PDF].

[h/t Co.Design]

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A Chemical in Bed Bug Poop Might Be Making You Feel Sick
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Bed bugs can give you nasty bites and a lifetime of nightmares, but scientists have long wondered if the creepy parasites can pass diseases to their hosts. For years, the general consensus was no: Unlike ticks, mosquitos, and other insects that are known to feast on human blood, bed bugs aren't packing any harmful pathogens in their bites. Yet according to a new study, spotted by Gizmodo, the bugs don't need to nibble on us to make us sick. Histamines in their poop might be aggravating our immune systems.

For their study, recently published in the journal PLOS One, scientists at North Carolina State University tested the dust in a bed bug-infested apartment complex. They found that samples from some infested homes had histamine levels 20 times higher than those without bed bugs. This was still the case three months after the buildings had been treated by exterminators.

Histamine is a chemical compound produced by our bodies. In small amounts, it works as a vital part of our immune system. It's activated in the presence of allergens, irritants, and pathogens. Say a puff of dust goes up your nose: Histamine is what prompts your body to sneeze it out. It's also the culprit behind the watery eyes, runny nose, and itchy skin you might experience during an allergy attack (which is why you might take an antihistamine to calm these symptoms).

But we're not alone in our ability to produce histamine. Recent research has shown that the chemical is present in bed bug feces. When the insects poop, they spray histamines into the same air that homeowners breathe. A few whiffs of the stuff is likely nothing to worry about, but scientists are concerned about the effects environmental histamine can have on people over an extended period of time. The chemical compound can cause allergic reactions on its own and possibly make us more vulnerable to existing allergens. The implications are especially serious for people with asthma.

"Dermal, nasal, or respiratory responses (e.g. bronchial reactivity) to histamine in clinical tests suggest that exposure to histamine in the environment would constitute a significant health risk, although information on environmental exposure is limited," the study authors write.

For now, scientists can do nothing but speculate on what these results might mean for public health. Humans are prepared to treat only histamine that's produced by our own bodies, and dealing with the effects on histamine spread by bed bugs is uncharted territory for doctors and scientists. How exactly bed bugs obtain the chemicals in the first place is also unclear, but researchers suspect that it's a combination of the blood they suck from us and histamine they make on their own as a type of pheromone, indicating to other bed bugs that a place is safe to invade.

Following this study, the North Carolina State scientists plan to conduct more intensive research on the impact histamine produced by bed bugs is having on the people who live with it. While the best way to eradicate histamine in bed bug poop is still a mystery, there are plenty of ways to deal with the bugs themselves if you suspect you have an infestation.

[h/t Gizmodo]

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