When orb-weaving spiders (Araneus ventricosus) trap male fireflies in their webs, they manipulate the flashing signals to mimic the typical flashes made by female fireflies. These feigned flashes then lure other males into the web where they become the spider’s next meal. However, we still don’t know if the spider’s venom or a bite itself is manipulating the firefly’s signal.
The discovery arose after Xinhua Fu, a study co-author and entomologist at Huazhong Agricultural University in China observed several male fireflies entangled in orb-weaving spider webs while working in the field. He rarely saw a female firefly trapped in a web and additional field trips revealed this sexually skewed pattern. Fu hypothesized that the spiders may be somehow manipulating the fireflies’ behavior to attract others.
To test this hypothesis that the spiders are manipulating the firefly’s signal, he recruited behavioral ecologists Daiqin Li and Shichang Zhang from Hubei University. The team conducted field experiments where they observed the firefly signals and spider behavior. The observations showed that the spider’s web captured male fireflies more often when the spider was there, compared to when it was away from the web.
After further analysis, they found that the signals created by male fireflies in webs with spiders present looked more like the signals made by free flying females. The trapped males used single-pulse signals that use only one lantern and not both.
An orb-weaving spider (Araneus ventricosus) with two ensnared male fireflies (Abscondita terminalis), one of which has a luminescent lantern (right). CREDIT: Xinhua Fu.
Interestingly, the ensnared male fireflies very rarely lured other males when they were alone in the web and the spider was not around. This suggests that the males were not altering their flashes as a kind of distress signal. The team believes that the spiders are altering the firefly’s signal.
“While the eyes of orb-web spiders typically support limited spatial acuity, they rely more on temporal acuity rather than spatial acuity for discriminating flash signals,” Li said in a statement. “Upon detecting the bioluminescent signals of ensnared male fireflies, the spider deploys a specialized prey-handling procedure involving repeated wrap-bite attacks.”
According to the team, the experiment reveals that some animals are capable of using indirect yet dynamic signaling to go after a very specific category of prey in nature. The team also believes that there could be many other undescribed examples of this kind of mimicry in nature waiting to be uncovered. Predators could be using sound, pheromones, or other means, and not just visual signals to fool their prey. This deceptive ability is not exclusive to the animal kingdom either. The South African daisy appears to trick flies into mating with it and depositing pollen.
“We propose that in response to seeing the ensnared male fireflies’ bioluminescent signals, the spider deployed a specialized-prey handling procedure based on repeated wrap bite attacks,” the team wrote in the study. “We also hypothesize that the male firefly’s neurotransmitters may generate a female-like flashing pattern.”
However, additional study is needed to determine what exactly is changing in the trapped firefly’s flashing pattern.
Kristy Murray was there at the very beginning. In 1999, the epidemiologist and tropical medicine expert, now a professor of pediatrics at Emory University, was part of the Centers for Disease Control and Prevention (CDC) team responding to the initial U.S. outbreak of West Nile virus in New York City. “It was my very first outbreak assignment,” Murray tells Popular Science. Thirty cases of unexplained encephalitis had been reported in the city, and it was up to Murray and her colleagues to figure out why. The cause was initially baffling. People had symptoms of paralysis, “which is very unusual to see in encephalitis,” she explains, and older adults comprised the majority of those worst off, despite viral paralysis often being most common in children. None of the patients had any relation or apparent connection to one another.
To figure out what was happening, Murray says she and the rest of the CDC team acted as “disease detectives.” The first clue came from interviewing family members of those who were sick. “The one thing that kept coming up is that many of them were active, and spent a lot of time outside,” says Muray. From there, and through home visits, a CDC entomologist narrowed the potential sources down to Culex mosquitoes. More false leads and confusing test results finally gave way to a West Nile virus identification, after birds in the Bronx Zoo also began to fall ill with encephalitis. In total, the investigation took about three weeks, says Murray.
Though the initial mystery was resolved relatively quickly (“especially for 1999,” notes Murray), uncertainties surrounding West Nile have lingered. When and where the worst outbreaks will occur remains unpredictable. Exactly why some people have no symptoms, while other infections prove deadly is unclear. There’s still no available vaccine or proven treatment.
It’s been 25 years since the mosquito borne virus was first found in the U.S.. In that quarter century, the disease has spread from New York City across all 48 contiguous states. “It’s everywhere–all over the map, literally,” says Murray. “There is no place in the [lower 48] where you can really hide from this pathogen.” Each year, 2024 included, West Nile virus cases are reported, with a peak between late July and October. Here’s what to know as this year’s season unfolds, what we still don’t know, and how experts recommend you protect yourself.
How does West Nile virus spread?
Birds are the primary host and reservoir for West Nile virus. The pathogen is mainly passed from host to host via mosquito bites. Culex mosquitos, a genus found worldwide and especially common in major cities, are the primary vector, transmitting the virus between birds or from birds to humans or horses. People and other mammals infected with the illness don’t produce a high enough concentration of viral particles to act as a reservoir and subsequently infect additional mosquitos. “Humans are what we call a dead end host,” says Gonzalo Vazquez-Propkopec, a disease ecologist and professor of environmental science at Emory University. Only a small proportion of cases are transferred between humans through blood transfusions and organ transplants.
Yet though we can’t generally pass the virus on to each other, mosquitos do plenty of work to spread it themselves. “It’s the most widespread viral vector borne disease in the United States, without a doubt,” says Murray. “It far surpasses any other.” Other non-viral vector-borne illnesses, like tick-borne Lyme’s disease, may affect more people each year. But Lyme is a bacterial disease with an effective antibiotic treatment. There is no approved therapeutic for treating West Nile.
Is 2024 a bad year for West Nile?
The CDC tracks West Nile cases, along with other arthropod-borne illnesses, through ArboNET. As of August 13, the federal agency has confirmed 174 West Nile cases in 30 different states, with double digit numbers in Texas, Louisiana, Nebraska, Nevada, and Arizona. Of these, 113 have been “neuroinvasive,” or the more severe variant of infection that causes neurological symptoms like encephalitis (brain swelling), or meningitis, which is swelling of the membrane surrounding the brain. So far, eight of those reported cases have proved deadly.
If you look at past years’ West Nile case numbers, fewer than 200 cases nationwide may not sound like much. However, it’s relatively early in the season and each confirmed case at this point likely represents many more hidden ones, says Murray.
In general, cases are vastly underreported because many cases are asymptomatic and many symptomatic infections are mild and difficult to distinguish from other viral infections, she explains. Fever, a rash on the torso, fatigue, aches, and malaise are how the majority of symptomatic West Nile cases present. Often, those infected don’t seek any treatment or testing. A small proportion of infections, less than one percent, turn more serious, affecting the brain and nervous system and becoming “neuroinvasive.” These cases can be life threatening. Survivors of neuroinvasive illness often end up with lifelong disabilities, says Kiran Thakur, a neurology professor at Columbia University who studies neuroinfectious disease.
Yet even those severe cases are undercounted because providers don’t always test and tests don’t always come back positive, she says. In 2022, 827 confirmed neuroinvasive cases were reported to the CDC, but the agency estimates that between 24,810 and 57,890 neuroinvasive infections occurred. Up to 15 percent of neuroinvasive cases are estimated to be fatal, notes Thakur.
Delays in testing and reporting also mean that it takes time for the CDC to learn about a confirmed case. “There’s a lag in reporting cases, typically by about two weeks,” Murray says, and we’re just getting into the peak transmission time now.
Given those caveats, “we are seeing a few more cases than we [usually] would at this time of year, and some earlier cases,” says Erin Staples, a physician and medical epidemiologist with CDC’s Division of Vector-Borne Diseases. The biggest wave of illness onset tends to come at the end of August and beginning of September, Staples says.
However, that doesn’t mean we’re guaranteed to have a terrible West Nile season nationwide. Predicting how this year’s season will progress over the next couple of months “is very difficult,” Staples tells Popular Science. Trends can shift rapidly and lots of variables contribute to an outbreak’s severity.
Year-to-year, West Nile levels and epicenters vary a lot. The virus may spike in the Northeast one season and then the Southwest the next. In 2003, there was a major outbreak, another came in 2012. As a result, experts consider it “cyclic”, peaking in waves that come about once a decade, says Vazquez-Prokopec. “It seems, roughly, that we’re due for another spike,” he adds.
Climate and rainfall are important. Warm temperatures and the right level of moisture can contribute to a mosquito boom. Bird immunity levels also play a role, he says. If most birds in a region have antibodies and are avoiding illness in a given year, then there will also be fewer human cases, as the reservoir is smaller, Vazquez-Prokopec explains. “It’s a very complex cycle,” he adds– which makes accurate forecasting hard.
Regardless of what unfolds in the next couple of months, Staples notes that right now is a critical time to take preventative measures.
How can we manage West Nile virus?
Through surveillance of mosquito populations and birds, cities keep tabs on the viral threat year to year. In addition, many municipalities also treat for Culex mosquitos with pesticide sprays dispersed from fogging vehicles and by targeting the aquatic larvae. Mosquitoes need water to breed, so applying insecticide to drainage ditches and catchment basins can help reduce their populations without inadvertently killing beneficial insects like pollinators, says Vazquez-Prokopec.
The CDC is researching preventative vaccines and antiviral treatments (and has been for years), says Staples–though the development process, which requires large scale human trials to prove efficacy, is challenging for such an unpredictable virus. A silver lining of the Covid-19 pandemic is that it made alternate pathways to FDA approval and licensure clearer, she adds.
But in the meantime, without a vaccine or medication to rely on, iIndividual people can mitigate their own risk by eliminating sources of standing moisture around their homes (ex: emptying buckets and kiddie pools). Then, there’s behavioral interventions.
“We have to exercise–not panic, but caution,” says Vazquez-Prokopec. Mosquitoes are more than a nuisance, they’re a public health problem, he says. So, he advises that people take earnest steps to avoid bites.
Insect repellents, specifically ones registered with the Environmental Protection Agency and recommended by the CDC, are a critical tool. Wearing loose fitting long sleeve shirts and pants helps to prevent bites as well. And people should be particularly mindful when going out around dusk and dawn when mosquitoes are most active. “I have a can of repellent by my front door and another by my back door, so I remember to [apply] before I walk outside,” says Staples.
It’s still not completely understood why some people become very sick while others have asymptomatic infections. However, some trends are clear and certain groups are known to be more vulnerable to severe West Nile virus. People who are immunocompromised, including those who take medications for autoimmune diseases, should be more vigilant, says Staples. People over the age of 50 are also at higher risk, says Murray. Severe neuroinvasive illness is more commonly reported among men, though that could be because men share a higher level of other risk factors, like working outdoors or comorbidities such as diabetes, notes Thakur. And ultimately, anyone can end up with a severe case.
West Nile virus may be benign for most people, and the worst consequences may be rare, but preventative steps are simple and accessible. When the stakes are so high, it’s best to take the risk seriously, says Thakur. Plus, the same strategies for avoiding West Nile will also help to minimize exposure to other vector borne diseases like Dengue or Powassan, Staples adds. ” “Another great reason to use your repellent,” she says.
Getting in the habit now will be good practice for our warming future, where we’ll all want to take biting bugs more seriously. Under climate change, mosquito seasons are likely to grow longer, and vector–borne illnesses, including West Nile, are set to spread into new regions where people have no prior exposure or immunity. As global warming progresses, “it’s a disease category I worry about a lot,” says Thakur.
Initial buzz about Grounded was minimal; just an inkling that something fresh might emerge in gaming. Yet its sudden explosion into mainstream consciousness proved otherwise; mesmerizing millions with its blend of survival, exploration, and crafting gameplay. Obsidian Entertainment seems to have created some form of magical shrinking potion that allows us to experience life from an ant's point of view! Grounded was an unexpected sensation that captured everyone's interest surprisingly early. A stealthy title that initially managed to stay under the radar before blossoming into something amazing and inspiring players around the globe; suddenly everyone was talking about survival in backyard environments!
Crafting Depth, Overcoming Challenges...
I have spent endless hours wandering among towering blades of grass, building intricate fortresses, and fighting massive insects that would send any arachnophobe shrieking with fear. It is an extraordinary world with beauty as well as fear; every dewdrop could provide life support while spiders could pose grave threats; its ability to transform everyday things into extraordinary experiences is truly astounding. Far from me to recommend to those who buy PS5 games a title that I did not finish and totally enjoyed it. Grounded may contain quirks - software bugs not of the garden variety - which are sometimes annoying, yet these issues are easily overlooked given its sheer joy of discovery. Every corner offers new challenges; discovering an underground cavern or crafting a powerful weapon are always exciting experiences in Grounded!
Stealth and Survival Mechanics
Survival mechanics in Antsy are deceptively deep for such an apparently straightforward premise, from gathering resources, crafting tools, and building your base to exploring your surroundings and fortifying against monstrous insects lurking behind every corner. I spent hours fortifying my base only for it to become overrun with angry ants; an experience both thrilling and frightening at once! A game about being shrunk down seemed like an odd choice of subject matter; yet once I ventured into that unfamiliar and overgrown world I became fascinated and became fully immersed in its strange beauty, creating an unparalleled feeling of discovery!
An Engaging Experience for Both Beginners and Veterans Alike
Every blade of grass and dewdrop holds something special to reveal; there's great pleasure in exploring this miniature world and piecing together what happened here. Grounded's humor also stands out: from absurdly large bugs to its quirky dialogue, Grounded, among PS5 adventure games, manages to be both frightening and delightful at the same time. Grounded stands as proof of what can be accomplished with fresh perspectives and taking risks; its success speaks for itself and millions are playing this beloved title!
Final Thoughts: Exceed Expectations
Obsidian Entertainment has conjured an immersive universe that is both intimate and massive in scale. A backyard that was once mundane transforms into an expansive wilderness where every dewdrop may become its own lake; every pebble becomes its own formidable mountain; not simply another take on "Honey, I Shrunk the Kids." Obsidian has created something bolder - an immersion into an alienated reality where survival becomes ever-present anxiety. Grounded isn't without its problems; performance issues may hinder gameplay at times and some of the later game content feels thin at times, yet these are minor drawbacks in what otherwise represents an exceptional package.
While humans won’t be regenerating entire limbs like sea stars, some new genetic work with fruit flies has yielded some surprising results. A team from the University of Tokyo found that certain genes from simple organisms that help them regenerate body parts and tissues can be transferred into other animals. These genes then suppressed an intestinal issue in the flies and could potentially reveal some new mechanisms for rejuvenation in more complex organisms. The findings are detailed in a study published August 1 in the journal BMC Biology.
Some animals including jellyfish and flatworms can regenerate their whole bodies. While scientists still don’t really know how, there are possibly specific genes that allow regeneration. These same genes may also maintain long-term stem cell functions.
Stem cells can divide and renew themselves over a long period of time and are kind of like a skeleton key. While they aren’t necessarily specialized, they can potentially become more specialized cells, including blood cells and brain cells, over time. Mammals and insects who have very limited regenerative skills may have lost these genes over the course of evolution.
“It is unclear whether reintroducing these regeneration-associated genes in low regenerative animals could affect their regeneration and aging processes,” study co-author and University of Tokyo Graduate School of Pharmaceutical Sciences biologist Yuichiro Nakajima said in a statement.
In this new study, Nakajima and the team focused on the group of genes that is unique to animals with high regenerative capacity like flatworms. These genes are called HRJDs, or highly regenerative species-specific JmjC domain-encoding genes. They transferred the HRJDs into the fruit fly (Drosophila melanogaster) and tracked their health with a blue dye. They nicknamed the fly Smurf, thanks to this hue.
Initially, they hoped that these HRJD-boosted fruit flies would regenerate tissue if injured. This didn’t happen. However, the team had a fruit fly intestine expert Hiroki Nagai onboard, who noticed something else. There were some novel phenotypes–or the characteristics like eye color or hair color that comes from a specific gene.
“HRJDs promoted greater intestinal stem cell division, whilst also suppressing intestinal cells that were mis-differentiating, or going wrong in aged flies,” said Nakajima.
This is different to how antibiotics may suppress the mis-differentiated intestinal cells, but suppress intestinal stem cell division.
“For this reason, HRJDs had a measurable effect on the lifespans of fruit flies, which opens the door, or at least provides clues, for the development of new anti-aging strategies,” said Nakajima. “After all, human and insect intestines have surprisingly much in common on a cellular level.”
Fruit flies are famous test subjects in biological research. They share 75 percent of the genes that cause diseases in humans, reproduce quickly, and their genetic code is fairly easy to change. However, even with their relatively short lives and rapid-fire reproduction and maturating rates, it still took about two months to study their full aging process.
In future studies, the team would like to take a closer look at how HRJD’s work on a molecular level.
“Details of the molecular workings of HRJDs are still unresolved. And it’s unclear whether they work alone or in combination with some other component,” said Nakajima. “Therefore, this is just the start of the journey, but we know now that our modified fruit flies can serve as a valuable resource to uncover unprecedented mechanisms of stem cell rejuvenation in the future. In humans, intestinal stem cells decrease in activity with age, so this research is a promising avenue for stem cell-based therapies.”
Last night, a swarm of bees invaded Chase Field in Phoenix, Arizona, just five minutes before a game between the Arizona Diamondbacks and Los Angeles Dodges was about to start. The bee colony swarmed into a large mass on the protective netting behind home plate. — Read the rest
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