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Are Bees Really All That Busy?

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If idioms are to be believed, bees are some of the most industrious animals around. But it’s a little more complicated than poet Isaac Watts made it out be be when he wrote “How doth the little busy bee / Improve each shining hour, / And gather honey all the day / From every opening flower!”

Some bees don’t really do any work at all, and are parasites of other bee species. These so-called “cuckoo bees” don’t collect pollen or build their own homes. Instead, they steal food from, and lay their eggs in, other bees’ nests. When the cuckoo bee larvae hatch, they eat their hosts’ pollen stores and sometimes their eggs if mom didn’t feast on them already. 

Other bee groups—the stingless bees, bumble bees and honey bees—are social insects that live together and work cooperatively. They put in honest work, unlike the cuckoo bees, but the amount of labor any one bee does varies with its role in the colony. The honey bee workers that forage food for the hive often do work “all the day,” like in the poem. Slate’s Forrest Wickman reports that these workers spend nearly every hour of daylight outside” and entomologists have seen them making more than 100 foraging trips in a day. But these guys strictly work the dayshift, and come home to relax when the sun goes down. Meanwhile, other workers whose jobs keep them home tending honeycombs and cooling the nest work around the clock, but also take frequent breaks. “Drones, by contrast, are quite lazy,” Wickman says. “They don’t leave the hive until early afternoon, at which time they carouse around in packs, and when they get home just a few hours later, they rely on the worker bees to feed them.”

Even among the foraging workers, the workload isn’t shared evenly and some bees are busier than others. New research suggests that it’s a small group of workers that do the bulk of the labor, while the others take it easy until conditions in the colony change and prompt them to get to work. 

For the study, researchers from the University of Illinois set up five experimental honeybee (Apis mellifera) colonies—three in natural outdoor areas and two inside screened enclosures. Each hive was equipped with pairs of laser scanners at its entrance, and 100 to 300 workers from each colony were tagged with tiny microtransponders. As these workers passed through the hive entrances, the scanners recorded the unique IDs of their tags, the direction they were traveling (that is, entering or exiting the hive) and the time of day. The setup allowed the researchers to track the workers as they came and went and tell how much time they spent out and about or in the hive, kind of like the time clocks that some businesses use to track employee hours. The scientists also used handheld scanners to record tagged bees’ visits to pollen and nectar feeders that they’d set up near the enclosed hives. 

After almost two months of gathering data while the bees went about their business, the researchers got a picture of the workers’ activity levels, and it showed that a small portion of bees were much busier than the rest. In all five hives, around 20 percent of the tagged workers accounted for half of the total recorded flight activity. These “elite” foragers, the researchers say, “began to make trips as soon as the colony became active each morning, and made regular, closely spaced trips throughout the day until the cessation of colony-wide flight activity in the evening.” 

The elite workers weren’t always busy, though, and their activity levels spiked and dipped over the course of the experiment and their lifetimes. That made the researchers think that the elite bees’ hard-working ways weren’t intrinsic, which team leader Gene Robinson says has always been the assumption with social insects, but adaptive. A worker might be more or less active in response to certain circumstances, like a favorite food source running low or new sources appearing. If the super foragers weren’t special, then maybe the other bees weren’t simply slackers, but more of a reserve work force also capable of elite behavior and just waiting for their time to shine. 

To see if the low-activity bees could and would step up their game when duty called, the researchers waited at the feeders near the enclosed hives during peak foraging time  and captured all the bees that arrived there. While they couldn’t specifically target known high-activity bees, the busier workers did have a higher chance of getting bee-napped because they made more trips. Sure enough, when the scientists checked the IDs of the captured bees and looked at their previous day’s flight records, most of the bees they removed were in the top 20 percent of the workforce. 

For the rest of the day after the cull, the feeders at both hives were quiet, with fewer than ten visits between them. The next day, though, foraging activity and the number of bees at the feeders returned to normal. The bees that had been taking it easy before were picking up the slack of their missing co-workers, some of them boosting their activity levels by almost 500 percent. The results, the researchers say, suggest that a hive isn’t divided into hard workers and slackers, but that every worker keeps tabs on the net activity of the colony and adjusts their own activity accordingly to make sure that the colony’s needs are being met. 

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There May Be an Ancient Reason Why Your Dog Eats Poop
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Dogs aren't known for their picky taste in food, but some pups go beyond the normal trash hunting and start rooting around in poop, whether it be their own or a friend's. Just why dogs exhibit this behavior is a scientific mystery. Only some dogs do it, and researchers aren't quite sure where the impulse comes from. But if your dog is a poop eater, it's nearly impossible to steer them away from their favorite feces.

A new study in the journal Veterinary Medicine and Science, spotted by The Washington Post, presents a new theory for what scientists call "canine conspecific coprophagy," or dogs eating dog poop.

In online surveys about domestic dogs' poop-eating habits completed by thousands of pet owners, the researchers found no link between eating poop and a dog's sex, house training, compulsive behavior, or the style of mothering they received as puppies. However, they did find one common link between the poop eaters. Most tended to eat only poop that was less than two days old. According to their data, 85 percent of poop-eaters only go for the fresh stuff.

That timeline is important because it tracks with the lifespan of parasites. And this led the researchers to the following hypothesis: that eating poop is a holdover behavior from domestic dogs' ancestors, who may have had a decent reason to tuck into their friends' poop.

Since their poop has a high chance of containing intestinal parasites, wolves poop far from their dens. But if a sick wolf doesn't quite make it out of the den in time, they might do their business too close to home. A healthier wolf might eat this poop, but the parasite eggs wouldn't have hatched within the first day or two of the feces being dropped. Thus, the healthy wolf would carry the risk of infection away from the den, depositing the eggs they had consumed away in their own, subsequent bowel movements at an appropriate distance before the eggs had the chance to hatch into larvae and transmit the parasite to the pack.

Domestic dogs may just be enacting this behavior instinctively—only for them, there isn't as much danger of them picking up a parasite at home. However, the theory isn't foolproof. The surveys also found that so-called "greedy eaters" were more likely to eat feces than dogs who aren't quite so intense about food. So yes, it could still be about a poop-loving palate.

But really, it's much more pleasant to think about the behavior as a parasite-protection measure than our best pals foraging for a delicious fecal snack. 

[h/t The Washington Post]

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What Makes a Cat's Tail Puff Up When It's Scared?
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Cats wear their emotions on their tails, not their sleeves. They tap their fluffy rear appendages during relaxing naps, thrash them while tense, and hold them stiff and aloft when they’re feeling aggressive, among other behaviors. And in some scary situations (like, say, being surprised by a cucumber), a cat’s tail will actually expand, puffing up to nearly twice its volume as its owner hisses, arches its back, and flattens its ears. What does a super-sized tail signify, and how does it occur naturally without help from hairspray?

Cats with puffed tails are “basically trying to make themselves look as big as possible, and that’s because they detect a threat in the environment," Dr. Mikel Delgado, a certified cat behavior consultant who studied animal behavior and human-pet relationships as a PhD student at the University of California, Berkeley, tells Mental Floss. The “threat” in question can be as major as an approaching dog or as minor as an unexpected noise. Even if a cat isn't technically in any real danger, it's still biologically wired to spring to the offensive at a moment’s notice, as it's "not quite at the top of the food chain,” Delgado says. And a big tail is reflexive feline body language for “I’m big and scary, and you wouldn't want to mess with me,” she adds.

A cat’s tail puffs when muscles in its skin (where the hair base is) contract in response to hormone signals from the stress/fight or flight system, or sympathetic nervous system. Occasionally, the hairs on a cat’s back will also puff up along with the tail. That said, not all cats swell up when a startling situation strikes. “I’ve seen some cats that seem unflappable, and they never get poofed up,” Delgado says. “My cats get puffed up pretty easily.”

In addition to cats, other animals also experience piloerection, as this phenomenon is technically called. For example, “some birds puff up when they're encountering an enemy or a threat,” Delgado says. “I think it is a universal response among animals to try to get themselves out of a [potentially dangerous] situation. Really, the idea is that you don't have to fight because if you fight, you might lose an ear or you might get an injury that could be fatal. For most animals, they’re trying to figure out how to scare another animal off without actually going fisticuffs.” In other words, hiss softly, but carry a big tail.

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