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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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Which Rooms In Your Home Have the Most Types of Bugs, According to Entomologists 
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Insects can make any home their own, so long as it contains cracks, doors, and windows for them to fly, wriggle, or hitchhike their way in. And it turns out that the creepy crawlers prefer your living room over your kitchen, according to a new study that was recently highlighted by The Verge.

Published in the journal Scientific Reports, the study looked at 50 homes in Raleigh, North Carolina, to measure their insect populations. Entomologists from both North Carolina State University and the California Academy of Sciences ultimately discovered more than 10,000 bugs, both alive and dead, and a diverse array of species to boot.

The most commonly observed bugs were harmless, and included ladybugs, silverfish, fruit flies, and book lice. (Luckily for homeowners, pests like bedbugs, termites, and fleas were scarcer.) Not all rooms, though, contained the same distribution of many-legged residents.

Ground-floor living rooms with carpets and windows tended to have the most diverse bug populations, as the critters had easy access inside, lots of space to live in, and a fibrous floor habitat that could be either a cozy homestead or a death trap for bugs, depending on whether they got stuck in it. The higher the floor level, the less diverse the bug population was, a fact that could be attributed to the lack of doors and outside openings.

Types of bugs that were thought to be specific to some types of rooms were actually common across the board. Ants and cockroaches didn’t limit themselves to the kitchen, while cellar spiders were present in all types of rooms. As for moths and drain flies, they were found in both common rooms and bathrooms.

Researchers also found that “resident behavior such as house tidiness, pesticide usage, and pet ownership showed no significant influence on arthropod community composition.”

The study isn’t representative of all households, since entomologists studied only 50 homes within the same geographical area. But one main takeaway could be that cohabiting bugs “are an inevitable part of life on Earth and more reflective of the conditions outside homes than the decisions made inside,” the researchers concluded. In short, it might finally be time to make peace with your itty-bitty housemates.

[h/t The Verge]

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UK Agrees to Ban Pesticides That Destroy Bee Populations
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As bee populations around the globe continue to dwindle, more countries are stepping up to save them. The latest nation taking action against the threat of pollinator decline is Britain. The UK’s environment secretary Michael Gove recently announced that the country will join the European Union in restricting a type of pesticide harming bees.

The decision was made in light of a German study reporting that the number of flying insects in some areas have declined by 75 percent in just a quarter of a decade. Of the species dying off en masse, bees are the most concerning: The insects pollinate a significant portion of our crops, and without them humans could face an agricultural crisis. “These particular flying insects are absolutely critical to the health of the natural world,” Gove wrote for The Guardian. “Without a healthy pollinator population we put the whole ecological balance of our world in danger.”

The alarming state of bee populations is likely a mix of several factors, but human-made insecticides are one of the biggest contributors. Neonicotinoids, the chemical compounds covered by the proposed ban, are the most commonly used insecticides on Earth, and they’ve also been shown to have devastating effects on bee colonies. Getting rid of them completely was first proposed by the European Union in 2013, and after initially opposing the move, the UK is finally getting on board.

Neonicotinoids are slowly being phased out in the U.S., where beekeepers have been reporting bees disappearing from their hives for the last decade or so. If you want to make your backyard a more hospitable place for your tiny, flower-loving neighbors, here are some ways you can help right now.

[h/t The Guardian]

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