May research highlights: Rapid river migration, bean plant defense, tiny tensegrities, more

How bean plants sense very hungry caterpillars and call for backup

Plants may not appear aggressive, but they can still defend themselves while under attack. When caterpillars chomp the leaves of bean plants, these plants release gases that lure predatory wasps. The wasps prey on the caterpillars, saving the plants from further destruction. In a paper published May 27 in Science Advances, a UW-led team demonstrated that this defense strategy is run by a protein called INR, or inceptin receptor. The researchers grew bean plants with naturally occurring mutations in the INR gene alongside plants with functional INR in an experimental field in Oaxaca, Mexico. The knock-out plants didn’t emit gases and attracted far fewer wasps. This result helps explain a previous study by this team that first identified the biochemical pathway behind this defense mechanism. These results also showcase how the tiny actions of a single protein can affect the behavior of wasps and caterpillars, and in turn, protect the health of the plant. This could benefit nearby plants as well, the researchers said. Beans are often grown alongside “companion crops,” such as corn, with the idea that each plant provides a benefit for the others. Beans help make the soil richer for their companions, and, through the actions of INR, could also protect their neighbors from pests.

For more information, contact senior author Adam Steinbrenner, UW associate professor of biology, at astein10@uw.edu.  

The other UW co-authors are Natalia Guayazán Palacios, Brian Behnken, Di Wu, Antonio Chaparro and Benjamin Sheppard. A full list of co-authors and funding is included in the paper.

Decades of satellite data show Himalayan rivers migrating rapidly in response to climate change

The movement of rivers is often described in terms of flowing water, but the path a river takes can also change. Some migration is normal, but in the Himalayas, rivers seem to be scrambling faster than scientists anticipated. In a study published May 14 in Science, researchers show that rivers in the Tibetan Plateau moved twice as much from 2000 to 2020 as they did from 1980 to 2000. As glaciers melt and frozen ground thaws in response to rising temperatures, rivers are inundated with silty meltwater from surrounding glaciers. The water picks the path of least resistance through softening ground. The “movement” includes small lateral shifts, big swings that cut off entire sections of river and occasionally, brand new routes. The international team attributes their observations to climate change, which is driving temperatures up faster here than many other places. More than 2 billion people rely on these rivers for fresh water and researchers are concerned about communities downstream, as well as the potential for similar patterns that may play out elsewhere.

For more information, contact co-author David Montgomery, UW professor of Earth and space sciences at bigdirt@uw.edu.  

A full list of co-authors and funding is included in the paper.

Researchers shrink eye-catching structure down to the nano scale 

Tensegrities are unique structures made using a network of freestanding bars suspended by a web of thin, tense cables. The organization of the bars and cables allows the network of tension and compression forces to lock everything into place, creating a lightweight yet stiff structure. Tensegrities of different sizes are common in nature — examples include spider webs and the cytoskeletons that help living cells maintain their shape — as well as in diverse manmade structures like planetary lander prototypes, bridges and art installations. Now, a team of engineers at the UW have found a way to create tensegrities as small as five micrometers across — roughly a tenth of the width of a human hair. In a recent paper published in the aptly-named journal Small, researchers used a specialized nanoscale 3D printer and a resin compound to print bar-and-cable structures about 30 micrometers across. They then heated the materials to 900 degrees celsius, causing the structures to shrink by over 80%. As they shrank, the thinner cables constricted more than the bars, resulting in nanostructures with specific, locked-in levels of stress that were up to 250% stiffer than the starting structures. The team is now working on ways to build larger materials composed of tiny tensegrities, which could eventually usher in a new class of stiff, light and impact-resistant materials.

For more information, contact lead author Amitha R. Mulastham, a UW doctoral student of mechanical engineering.

Other UW co-authors are Caelan Wisont, Robert Verdoes, Zainab S. Patel, Alex Cong, Matt Leahy and Lucas R. Meza. Funding information is included in the paper. 

Scientists find a key water source for atmospheric rivers

In December 2025, a series of strong atmospheric rivers brought a seemingly endless onslaught of precipitation to Washington that caused 33 rivers to flood and washed away roads and homes. In a recent study published in the Journal of Geophysical Research: Atmospheres, UW researchers help explain where all that water came from. They describe a link between the Madden-Juilian Oscillation, a weather pattern that brings moisture east across the Pacific, and atmospheric rivers. Hypotheses about this connection have emerged from previous studies, but researchers couldn’t physically draw it until now. By tracking precipitation and wind patterns from 2000 to 2024, the UW researchers show that heavy rainfall and flooding are more likely when MJO is active, which happens several times a year. By identifying the MJO as a key moisture source for powerful atmospheric rivers, the researchers hope to improve forecast accuracy and give people more lead time to prepare for incoming storms.

For more information, contact co-author Shuyi Chen, UW professor of atmospheric and climate science at shuyic@uw.edu.

Other UW co-authors are Chad Small and Brandon Kerns. Funding information is included in the paper.