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."

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.”