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Across the forest floor near Manaus in northern Brazil, small clay towers mark the final underground stage of the architect cicada Guyalna chlorogena.<\/p>\n
Working through Serrapilheira Institute\u2019s training program<\/a>, the research team documented how these towers alter the conditions surrounding the developing insects.<\/p>\n Observations showed that the structures change how the nymph responds when air circulation inside the tower is disrupted.<\/p>\n Those responses point to the towers acting as functional extensions of the cicada\u2019s own body, a finding that sets up the evidence from predator and airflow experiments that follow.<\/p>\n Ants on patrol<\/p>\n For the predator test, the team placed bait on tower tops and on the ground beside them.<\/p>\n Marina M\u00e9ga, a doctoral student in ecology at the Federal University of Rio de Janeiro (UFRJ<\/a>), had already noticed ants around the towers.<\/p>\n \u201cThere were eight times fewer ants on the towers than on the ground,\u201d wrote M\u00e9ga.<\/p>\n That simple height advantage suggests the towers buy time during metamorphosis, when the insects cannot dig back into safety.<\/p>\n Latex seals air<\/p>\n To test breathing, the researchers slipped latex condoms over the towers and sealed the edges with plastic film.<\/p>\n That barrier stopped fresh air from moving through the clay, creating respiratory stress for insects still underground.<\/p>\n In the published paper<\/a>, the sealed towers triggered different rebuilding responses once the researchers broke them open the next day.<\/p>\n A direct manipulation like that mattered because older explanations relied mostly on watching towers, not on forcing them to fail.<\/p>\n Cicada tower size<\/p>\n Once air flow was blocked, tower size started to matter in ways earlier observations had only hinted at.<\/p>\n Larger towers showed faster growth after the seal was removed, while smaller ones rebuilt less by the next morning.<\/p>\n More clay <\/a>and more internal space may have buffered stale air, giving bigger structures a better margin under stress.<\/p>\n That uneven response helps explain why Amazon towers vary so much in height instead of following one standard design.<\/p>\n Bodies beyond skin<\/p>\n At that point, the study moved from describing a structure to redefining what counted as part of the insect.<\/p>\n The authors called the tower<\/a> an extended phenotype, a body-related trait expressed through something an organism builds outside itself.<\/p>\n In plain terms, the cicada shaped mud into a survival tool that continued the job of keeping its body stable.<\/p>\n That idea matters beyond word choice, because it treats the tower as biology in action rather than leftover dirt.<\/p>\n Older clues return<\/p>\n Years before this experiment, earlier work<\/a> had already shown that one cicada occupied each tower and rebuilt it night after night.<\/p>\n That study also found openings appeared when conditions changed, which hinted that the towers were responding to the environment.<\/p>\n Because wet clay can clog tiny air spaces, opening the top may help oxygen move and carbon dioxide escape.<\/p>\n The new experiment gave those older clues a harder test, and the two studies now fit together.<\/p>\n Danger above ground<\/p>\n Near the end of development, each cicada nymph, the immature stage before adulthood, has to leave the soil and climb.<\/p>\n During those hours, the insect<\/a> cannot hide easily, and any ant patrol can turn exposure into injury or death.<\/p>\n A raised tower changes that encounter by lifting the animal off the ground, where ants were far more likely to gather.<\/p>\n Protection and breathing support fit the same moment in the life cycle, which is why the result feels coherent.<\/p>\n Fieldwork makes proof<\/p>\n Deep in the central Amazon, the project grew out of a training course rather than a long-funded laboratory campaign.<\/p>\n Long trails, humid heat, and limited gear pushed the team toward simple tests that changed conditions without fancy equipment.<\/p>\n That context helps explain why 40 condoms ended up in the field kit, solving a clean experimental problem in minutes.<\/p>\n Good field science often looks improvised on the surface, while the real strength comes from changing one thing clearly.<\/p>\n Questions still open<\/p>\n One result still hangs in the air<\/a>, because the biggest towers may handle stress differently for more than one reason.<\/p>\n Extra height could change airflow, but it could also reflect stronger builders, different soil, or slightly different moisture.<\/p>\n The field team also reported a tower about 18 inches tall, an unusual outlier that hints at bigger variation.<\/p>\n Those loose ends keep the story alive, because a strange tower becomes more interesting once its function is no longer strange.<\/p>\n Why cicada towers matters<\/p>\n What emerged from these tests is a sharper picture of how a hidden insect engineers a safer path into adult life.<\/p>\n Researchers now have a clearer target for future work, including how soil, rain, and tower size combine to shape survival.<\/p>\n The study is published in Biotropica<\/a>.<\/p>\n \u2014\u2013<\/p>\n Like what you read? Subscribe to our newsletter<\/a> for engaging articles, exclusive content, and the latest updates.<\/p>\n Check us out on EarthSnap<\/a>, a free app brought to you by Eric Ralls<\/a> and Earth.com.<\/p>\n \u2014\u2013<\/p>\n","protected":false},"excerpt":{"rendered":"Researchers have found that clay towers built by young Amazonian cicadas protect the insects from predators and help…\n","protected":false},"author":2,"featured_media":538457,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[49,48,66],"class_list":["post-538456","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-ca","tag-canada","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/538456","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=538456"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/538456\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/538457"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=538456"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=538456"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=538456"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}