Enlarge / Bumblebees can learn to solve puzzles from experienced peers. Honeybees do the same to learn their waggle dances. (credit: Diego Perez-Lopez, PLoS/CC-BY 4.0 )

Social insects like bees demonstrate a remarkable range of behaviors, from working together to build structurally complex nests (complete with built-in climate control) to the pragmatic division of labor within their communities. Biologists have traditionally viewed these behaviors as pre-programmed responses that evolved over generations in response to external factors. But two papers last week reported results indicating that social learning might also play a role.

The first, published in the journal PLoS Biology, demonstrated that bumblebees could learn to solve simple puzzles by watching more experienced peers. The second , published in the journal Science, reported evidence for similar social learning in how honeybees learn to perform their trademark "waggle dance" to tell other bees in their colony where to find food or other resources. Taken together, both studies add to a growing body of evidence of a kind of "culture" among social insects like bees.

"Culture can be broadly defined as behaviors that are acquired through social learning and are maintained in a population over time, and essentially serves as a 'second form of inheritance,' but most studies have been conducted on species with relatively large brains: primates, cetaceans, and passerine birds," said co-author Alice Bridges , a graduate student at Queen Mary University of London who works in the lab of co-author Lars Chittka . "I wanted to study bumblebees in particular because they are perfect models for social learning experiments. They have previously been shown to be able to learn really complex, novel, non-natural behaviors such as string-pulling both individually and socially."

Enlarge / Even hermit crabs have individual patterns of behavior — personalities, if you like. When scientists ignore the effects of such differences, they may produce research that’s flawed. (credit: NurPhoto via Getty Images )

Several years ago, Christian Rutz started to wonder whether he was giving his crows enough credit. Rutz, a biologist at the University of St. Andrews in Scotland, and his team were capturing wild New Caledonian crows and challenging them with puzzles made from natural materials before releasing them again. In one test , birds faced a log drilled with holes that contained hidden food, and could get the food out by bending a plant stem into a hook. If a bird didn’t try within 90 minutes, the researchers removed it from the dataset.

But, Rutz says, he soon began to realize he was not, in fact, studying the skills of New Caledonian crows. He was studying the skills of only a subset of New Caledonian crows that quickly approached a weird log they’d never seen before—maybe because they were especially brave, or reckless.

The team changed its protocol. They began giving the more hesitant birds an extra day or two to get used to their surroundings, then trying the puzzle again. “It turns out that many of these retested birds suddenly start engaging,” Rutz says. “They just needed a little bit of extra time.”

Juvenile snapping shrimp now hold the acceleration record for a repeatable body movement underwater. They can snap their claws at accelerations on par with a bullet shot from a gun. (credit: Harrison and Patek, 2023)

The snapping shrimp , aka the pistol shrimp, is one of the loudest creatures in the ocean, thanks to the snaps produced by its whip-fast claws. And juvenile snapping shrimp are even faster than their fully grown elders, according to a recent paper published in the Journal of Experimental Biology. Juvenile claws accelerate as fast as a bullet shot from a gun when they snap, essentially setting a new acceleration record for a repeated movement performed underwater.

As we've reported previously, the source of that loud snap is an impressive set of asymmetrically sized claws; the larger of the two produces the snap. Each snap also produces a powerful shockwave that can stun or even kill a small fish. That shockwave produces collapsing bubbles that emit a barely visible flash of light—a rare natural example of sonoluminescence .

Scientists believe that the snapping is used for communication, as well as for hunting. A shrimp on the prowl will hide in a burrow or similar obscured spot, extending antennae to detect any passing fish. When it does, the shrimp emerges from its hiding place, pulls back its claw, and lets loose with a powerful snap, producing the deadly shockwave. It can then pull the stunned prey back into the burrow to feed.

Enlarge / A digital reconstruction of a humpback whale engaged in trap feeding. (credit: John McCarthy, Flinders University)

About 10 years ago, marine biologists witnessed two different species of whales in different geographic locations engaged in a novel feeding strategy.  The whales would position themselves at the water's surface and stay motionless with their mouths wide open. Fish would swim into their mouths, and the whales would snap their jaws and swallow. It's been dubbed trap feeding, or tread-water feeding. A clip of whales engaged in trap feeding even went viral on Instagram in 2021.

Yet this feeding strategy might not be as recent as scientists initially thought. Researchers at Flinders University in Australia have found striking descriptions of what sounds a lot like trap feeding in Old Norse descriptions of the behavior of a sea creature called the hafgufa , according to a new paper published in the journal Marine Mammal Science. That creature, in turn, can be traced back to medieval bestiaries and a type of whale called aspidochelone , first mentioned in a 2nd century CE Alexandrian manuscript called the Physiologus .

“It’s exciting because the question of how long whales have used this technique is key to understanding a range of behavioral and even evolutionary questions," said co-author Erin Sebo , a medievalist at Flinders University. "Marine biologists had assumed there was no way of recovering this data but, using medieval manuscripts, we’ve been able to answer some of their questions."

The glassy-winged sharpshooter drinks huge amounts of water and thus pees frequently, expelling as much as 300 times its own body weight in urine every day. Rather than producing a steady stream of urine, sharpshooters form drops of urine at the anus and then catapult those drops away from their bodies at remarkable speeds, boasting accelerations 10 times faster than a Lamborghini. Georgia Tech scientists have determined that the insect uses this unusual "superpropulsion" mechanism to conserve energy, according to a new paper published in the journal Nature Communications.

A type of leafhopper , the glassy-winged sharpshooter ( Homalodisca vitripennis) is technically an agricultural pest, the bane of California winemakers in particular since the 1990s. It feeds on many plant species (including grapes), piercing a plant's xylem (which transports water from the roots to stems and leaves) with its needle-like mouth to suck out the sap. The insects consume a lot of sap, and their frequent urination consumes a lot of energy in turn, because of their small size and the sap's viscosity and negative surface tension (it naturally gets sucked inward). But the sap is about 95 percent water, so there's not much nutritional content to fuel all that peeing.

“If you were only drinking diet lemonade, and that was your entire diet, then you really wouldn’t want to waste energy in any part of your biological process,” co-author Saad Bhamla of Georgia Tech told New Scientist . “That’s sort of how it is for this tiny organism.”

Enlarge / Artist's impression of a "liquid window' prototype inspired by the structure of squid skin. (credit: Raphael Kay, Adrian So)

Squid and several other cephalopods can rapidly shift the colors in their skin, thanks to that skin's unique structure. Engineers at the University of Toronto have drawn inspiration from the squid to create a prototype for "liquid windows" that can shift the wavelength, intensity, and distribution of light transmitted through those windows, thereby saving substantially on energy costs. They described their work in a new paper published in the Proceedings of the National Academy of Sciences.

“Buildings use a ton of energy to heat, cool, and illuminate the spaces inside them,” said co-author Raphael Kay . “If we can strategically control the amount, type, and direction of solar energy that enters our buildings, we can massively reduce the amount of work that we ask heaters, coolers, and lights to do.” Kay likes to think of buildings as living organisms that also have "skin," i.e., an outer layer of exterior facades and windows. But these features are largely static, limiting how much the building "system" can be optimized in changing ambient conditions.

Installing blinds that can open and close is a crude means of easing the load on lighting and heating/cooling systems. Electrochromatic windows that change their opacity when a voltage is applied are a more sophisticated option. But, per Kay, these systems are pricey and have complicated manufacturing processes and a limited range of opacities. Nor is it possible to shade one part of a windowpane but not another.

Enlarge / "I spy with my dolphin eye... something that looks like prey!" (credit: Ridgway et al., 2022, PLOS ONE/CC-BY 4.0 )

There's rarely time to write about every cool science-y story that comes our way. So this year, we're once again running a special Twelve Days of Christmas series of posts, highlighting one science story that fell through the cracks in 2022, each day from December 25 through January 5. Today: Scientists attached video cameras onto dolphins to capture the sights and sounds of the animals as they hunted for prey to learn more about their feeding behavior.

Scientists attached GoPro cameras to six dolphins and captured the sights and sounds of the animals as they hunted and devoured various species of fish—even squealing in victory at the capture of baby sea snakes, according to an August paper published in the journal PLoS ONE. While sound and video has previously been recorded for dolphins finding and eating dead fish, per the authors, this is the first footage combining sound and video from the dolphins' point of view as they pursued live prey while freely swimming. The audio element enabled the scientists to learn more about how the dolphins communicated while hunting.

Sam Ridgway and his colleagues at the National Marine Foundation in San Diego, California, have conducted previous research on dolphins. They thought they could learn even more about the animals' hunting and feeding strategies using inexpensive commercial GoPro cameras to record sounds as well as visuals. The high frames per second (60, 90, or 120 FPS) enabled them to observe changes in behavior frame by frame.

Enlarge / This bee seems to having a grand old time rolling this colored wooden ball. (credit: Samadi Galpayage)

There's rarely time to write about every cool science-y story that comes our way. So this year, we're once again running a special Twelve Days of Christmas series of posts, highlighting one science story that fell through the cracks in 2020, each day from December 25 through January 5. Today: Scientists captured bees rolling wooden balls, solely for fun, on video, providing additional evidence that bees might experience positive "feelings."

Many animals are known to engage in play—usually large-brained mammals (like humans) and birds. Now scientists think they have observed genuine play behavior in bees, which were filmed rolling small colored wooden balls, according to an October paper published in the journal Animal Behavior.

“This research provides a strong indication that insect minds are far more sophisticated than we might imagine," said co-author Lars Chittka of Queen Mary University of London and author of a recent book, The Mind of a Bee . "There are lots of animals who play just for the purposes of enjoyment, but most examples come from young mammals and birds."