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.
