A group of fireflies twinkling on a summer's night may look peaceful, but those flashing lights can send an unsettling message: 'If you eat me, you'll regret it.' That's what a team of researchers discovered when conducting a study published in Science Advances.
According to the new research, reported by ScienceNews, a firefly's flashing behind acts as a warning signal to predators like big brown bats. Entomologists have long known that fireflies use their lights to attract mates, but the suspicion that they also use them to avoid becoming dinner wasn't confirmed until recently.
To investigate this theory, a team of scientists from Boise State University and other institutions exposed fireflies to three bats with no experience hunting the insects. Fireflies contain toxic chemicals that make them unappealing to predators. After tasting a few of the bugs and spitting them out, the bats learned to stop going after them altogether.
To see what part light played in these interactions, the researcher conducted a separate experiment. They attached tiny paper belts to each firefly and painted them with two coats of black paint—a process that took about 45 minutes for each specimen. The result was a cloak that effectively hid the fireflies' light show. When bats were set loose on the snuffed-out group, it took the predators about twice the amount of time to realize the fireflies were toxic and ignore them. With no visual warning signs to tip the bats off, the study authors suspect that the bats eventually learned to identify the insects from their flight patterns via echolocation.
Fireflies don't light up only when they see a bat swooping their way: Males each have their own "flash fingerprints" they use to attract mates, and females blink in response when they see a display they like. The new study suggests that predators' reaction to this bioluminescent adaptation may have influenced its evolution.
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By this point, your eco-friendly pal probably has a reusable water bottle that accompanies them everywhere and some sturdy grocery totes that keep their plastic-bag count below par. Here are 10 other sustainable gift ideas that’ll help them in their conservation efforts.
1. Reusable Produce Bags; $13
The complimentary plastic produce bags in grocery stores aren’t great, but neither is having all your spherical fruits and vegetables roll pell-mell down the checkout conveyor belt. Enter the perfect alternative: mesh bags that are nylon, lightweight, and even machine-washable.
Saying goodbye to disposable tea bags calls for a quality tea diffuser, and there’s really no reason why it shouldn’t be shaped like an adorable animal. This “ParTEA Pack” includes a hippo, platypus, otter, cat, and owl, which can all hang over the edge of a glass or mug. (In other words, you won’t have to fish them out with your fingers or dirty a spoon when your loose leaf is done steeping.)
Typing your notes on a tablet or laptop might save trees, but it doesn’t quite capture the feeling of writing on paper with a regular pen. The Rocketbook, on the other hand, does. After you’re finished filling a page with sketches, musings, or whatever else, you scan it into the Rocketbook app with your smartphone, wipe it clean with the microfiber cloth, and start again. This one also comes with a compatible pen, but any PILOT FriXion pens will do.
It’s hard to compete with the convenience of plastic wrap or tin foil when it comes to covering the exposed end of a piece of produce or an open tin can—and keeping those leftovers in food storage containers can take up valuable space in the fridge. This set of five silicone Food Huggers stretch to fit over a wide range of circular goods, from a lidless jar to half a lemon.
Swiffers may be much less unwieldy than regular mops, but the disposable pads present a problem to anyone who likes to keep their trash output to a minimum. These machine-washable pads fasten to the bottom of any Swiffer WetJet, and the thick microfiber will trap dirt and dust instead of pushing it into corners. Each pad lasts for at least 100 uses, so you’d be saving your eco-friendly friend quite a bit of money, too.
A fondness for fizzy over flat water doesn’t have to mean buying it bottled. Not only does the SodaStream let you make seltzer at home, but it’s also small enough that it won’t take up too much precious counter space. SodaStream also sells flavor drops to give your home-brewed beverage even more flair—this pack from Amazon ($25) includes mango, orange, raspberry, lemon, and lime.
There’s a good chance that anyone with a pet (or just an intense dislike for lint) has lint-rolled their way through countless sticky sheets. iLifeTech’s reusable roller boasts “the power of glue,” which doesn’t wear off even after you’ve washed it. Each one also comes with a 3-inch travel-sized version, so you can stay fuzz-free on the go.
Even if you keep a compost pile in your own backyard, it doesn’t make sense to dash outside every time you need to dump a food scrap. A countertop compost bin can come in handy, especially if it kills odors and blends in with your decor. This 1.3-gallon pail does both. It’s made of stainless steel—which matches just about everything—and contains an activated-charcoal filter that prevents rancid peels and juices from stinking up your kitchen.
Nobody likes starchy, scratchy clothes, but some people might like blowing through bottles of fabric softener and boxes of dryer sheets even less. Smart Sheep is here to offer a solution: wool dryer balls. Not only do they last for more than 1000 loads, they also dry your laundry faster. And since they don’t contain any chemicals, fragrances, or synthetic materials, they’re a doubly great option for people with allergies and/or sensitive skin.
While plenty of devices are rechargeable themselves, others still require batteries to buzz, whir, and change the TV channel—so it’s good to have some rechargeable batteries on hand. In addition to AA batteries, AAA batteries, and a charger, this case from Panasonic comes with tiny canisters that function as C and D batteries when you slip the smaller batteries into them.
Researchers are one step closer to understanding the mechanisms behind "cytokine storms," an immune system reaction that can cause severe COVID-19 symptoms in patients infected with the coronavirus. In a new paper published in the journal Cell, scientists from St. Jude Children's Research Hospital describe their identification of the specific cytokines, or small proteins, that are produced by the body in an effort to fight the virus but sometimes overreact and wind up causing damage, including inflammation, lung injury, and organ failure.
After examining the many different kinds of cytokines in the body, researchers determined that no single cytokine caused this inflammatory response. Instead, it appears to be a combination of two specific cytokines, dubbed tumor necrosis factor (TNF)-alpha and interferon (INF)-gamma, that work in collusion to cause inflammatory cell death.
By identifying these proteins as the culprit, researchers suggested that administering neutralizing antibodies and disrupting the protein pathways that promote cell death might present a new treatment method for COVID-19.
"Understanding the pathways and mechanism driving this inflammation is critical to develop effective treatment strategies," co-author Thirumala-Devi Kanneganti, vice chair of St. Jude's department of immunology, said in a press release. "This research provides that understanding. We also identified the specific cytokines that activate inflammatory cell death pathways and have considerable potential for treatment of COVID-19 and other highly fatal diseases, including sepsis."
Thus far, this theory has only been tested in mice, which received neutralizing antibodies and were protected from severe COVID-19 symptoms. But in isolating the exact cytokines involved, it will likely be easier to locate an effective treatment, either from an existing drug or one developed specifically for the task. In time, researchers hope clinical trials of select drugs can be another tool in the fight against the virus.