Streetlights are trapping thousands of pill bugs in giant “death spirals”

 

Researchers have uncovered a surprising side effect of artificial lighting: ordinary streetlights can lure thousands of tiny land dwelling isopods into giant synchronized "death spirals." The newly documented behavior, observed in Israel, is the first of its kind and suggests that human made lighting can dramatically disrupt the instincts of small ground dwelling animals.

The study was led by PhD student Idan Sheizaf under the supervision of Prof. Ariel Chipman at The Hebrew University of Jerusalem. Published in Ecology and Evolution, the research describes how land dwelling isopods, relatives of crabs and shrimp that are better known as woodlice or pill bugs, abandon their normally solitary habits to join enormous circular formations containing more than 5,000 individuals.

A surprising discovery in northern Israel

The unusual behavior first came to light after amateur naturalist Eviatar Itzkovich noticed huge swirling groups of isopods during summer nights in the Golan Heights.

The researchers focused on the species Armadillo sordidus, a little studied isopod that typically spends its time hidden beneath rocks and damp leaf litter, where moisture helps prevent it from drying out.

Although woodlice commonly cluster together to conserve moisture, scientists had never documented coordinated movement on this scale. Before this work, very little was known about A. sordidus. The study also expanded the species' known range. Previously, it had only been recorded in southern Syria and the Golan Heights. Researchers have now documented it in the Jezreel Valley for the first time.

Experiments reveal the role of artificial light

To determine what was causing the strange circular marches, the team tested several possible explanations, including magnetic fields and different types of lighting.

Strong magnets placed near the moving isopods had no effect, even though the Golan Heights is known for unusual magnetic properties. The animals continued circling uninterrupted.

Ultraviolet flashlights attracted only a small number of isopods and never triggered the swirling formations.

White light, however, consistently produced the dramatic behavior. When researchers positioned a white lamp so that its beam shone straight down, the isopods repeatedly gathered into large rotating circles.

The experiments showed that the shape of the illuminated area is what matters most. A vertical beam creates a circular boundary of light on the ground. Drawn toward that edge, the isopods begin walking along its perimeter. As more individuals join, the movement reaches a tipping point and develops into a large, self sustaining circular procession.

Reflecting on the findings, Idan Sheizaf said: "While collective movement is common in the animal kingdom, seeing it in this form in isopods was entirely unexpected. It appears that the geometry of our modern world -- specifically the circular pools of light created by streetlights, is interacting with the natural instincts of these creatures to create a mesmerizing, yet potentially harmful, emergent phenomenon."

Why the "death spirals" may be dangerous

Although the swirling formations are visually striking, researchers believe they represent an unintended trap created by artificial light at night (ALAN), not a natural social behavior.

Most of the participants were female, and many were carrying eggs, making it unlikely that the gatherings were related to mating. Instead, the evidence suggests that artificial lighting is disrupting the animals' normal instincts.

The consequences could be severe. During one observation, a centipede preyed on the distracted isopods while they remained caught in the swirling formation. By pulling these animals out of their sheltered habitats and keeping them moving in circles, streetlights may leave them vulnerable to predators while also wasting energy needed for survival.

The findings highlight how even a simple change to the environment, such as installing a streetlight, can reshape ancient behaviors in small animals that often go unnoticed.

Journal Reference:

1. Idan Sheizaf, Eviatar Itzkovich, Ariel D. Chipman. A Novel Light‐Induced Collective Circular Movement in Armadillo sordidus Isopods. Ecology and Evolution, 2026; 16 (4) DOI: 10.1002/ece3.73487

Courtesy:

 The Hebrew University of Jerusalem. "Streetlights are trapping thousands of pill bugs in giant “death spirals”." ScienceDaily. ScienceDaily, 6 July 2026. <www.sciencedaily.com/releases/2026/06/260626125707.htm>. 

Scientists solve a 30-year rye pollen mystery that could transform cancer research

 

Nearly 30 years ago, researchers discovered two unusual molecules in rye pollen that appeared to slow tumor growth in animal studies. Despite the promising findings, the research reached a dead end because scientists could not determine the molecules' exact three dimensional structures.

Now, chemists at Northwestern University have solved that long standing mystery. By constructing the molecules from scratch in the laboratory, they confirmed the precise structures of secalosides A and B for the first time.

With an accurate molecular blueprint available, researchers can now investigate how these compounds from rye pollen, which comes from a cereal crop widely grown for its grain, interact with the immune system. That knowledge could eventually help guide the development of new approaches to cancer treatment.

The findings were published in the Journal of the American Chemical Society.

"In preliminary studies, other researchers found that rye pollen could help different animal models clear tumors through some unknown, non-toxic mechanism," said Northwestern's Karl A. Scheidt, who led the study. "Now that we confirmed the structure of these molecules, we can find the active ingredient -- or what part of the molecule is doing the work. This is an exciting starting point to make better versions of these molecules that could possibly inform approaches to cancer therapy."

Scheidt is a professor of chemistry at Northwestern's Weinberg College of Arts and Sciences and a professor of pharmacology (by courtesy) at Northwestern University Feinberg School of Medicine. He also is a member of the Chemistry of Life Processes Institute and of the Robert H. Lurie Comprehensive Cancer Center of Northwestern University.

Nature's Role in Drug Discovery

Many important medicines have their roots in nature. Scientists have long studied plants, fungi, and microbes for compounds that can inspire new treatments.

Morphine, a powerful pain medication, comes from the opium poppy. Taxol, an important chemotherapy drug, was first isolated from the Pacific yew tree. Statins, which help lower cholesterol and reduce the risk of heart disease, originated from fungi.

"Natural products aren't necessarily effective drugs on their own, but they are great leads," Scheidt said. "We can find inspiration in natural products and use chemistry to make better versions that are orally available, survive the metabolism and hit the right targets."

Rye pollen could eventually join that list. Rye pollen extract is already sold as a dietary supplement that many people use to support prostate health. However, scientists have not yet developed it into a pharmaceutical treatment. A major obstacle was the lack of a clear picture of the molecules' three dimensional structures.

Solving a Decades Long Molecular Puzzle

Traditional techniques, including advanced nuclear magnetic resonance spectroscopy, could not fully determine how key parts of the molecules were arranged. As a result, scientists spent decades debating between two possible structural models.

Both versions contained the same atoms connected in the same way and shared the same overall shape. The difference was that one critical region existed as a mirror image in each model. Even that subtle variation can dramatically affect how a molecule interacts with biological targets and whether it produces a biological effect.

"It's like your hands," Scheidt said. "They are mirror images of each other, but you need a different glove for each. If you had two left-handed gloves, it wouldn't work because your hands can't be superimposed on top of one another."

Building the Molecules From Scratch

To resolve the uncertainty, the Northwestern team relied on total synthesis, a process in which researchers build a natural molecule step by step in the laboratory.

The work proved exceptionally difficult because secalosides A and B contain an extremely rare, highly strained 10 membered ring at their core. That tightly compressed structure is notoriously challenging to assemble.

The researchers overcame the problem by first creating a larger, more flexible ring. They then triggered a chemical reaction that converted it into the smaller strained ring in a single step.

After producing both proposed versions of the molecules, the team compared them with samples extracted from rye pollen. Only one matched perfectly, allowing the researchers to definitively identify the correct structures.

"We've demonstrated we can make the core of this natural product," Scheidt said. "Now, we're trying to find potential collaborators in immunology who could help us translate this to a possible clinical endpoint."

The study, "Synthesis and structural confirmation of secalosides A and B," was supported by the National Institute of General Medical Science, the Chemistry of Life Processes Institute Lambert Fellowship and the National Science Foundation.

Journal Reference:

1. Yunchan Nam, Anthony T. Tam, Troy E. Reynolds, Diego N. Rojas, Jonathan A. Brekan, Sneha Sil, Karl A. Scheidt. Synthesis and Structural Confirmation of Secalosides A and B. Journal of the American Chemical Society, 2025; 148 (1): 86 DOI: 10.1021/jacs.5c18864

Courtesy:

 Northwestern University. "Scientists solve a 30-year rye pollen mystery that could transform cancer research." ScienceDaily. ScienceDaily, 6 July 2026. <www.sciencedaily.com/releases/2026/06/260625014838.htm>.