{"id":15092,"date":"2026-01-18T08:03:03","date_gmt":"2026-01-18T08:03:03","guid":{"rendered":"https:\/\/readtrends.com\/en\/moth-plant-ultrasound-egglaying\/"},"modified":"2026-01-18T08:03:03","modified_gmt":"2026-01-18T08:03:03","slug":"moth-plant-ultrasound-egglaying","status":"publish","type":"post","link":"https:\/\/readtrends.com\/en\/moth-plant-ultrasound-egglaying\/","title":{"rendered":"Moths &#8216;hear&#8217; stressed plants and avoid laying eggs, study finds"},"content":{"rendered":"<article>\n<p>Female Egyptian cotton leafworm moths (Spodoptera littoralis) use more than sight and smell when choosing egg sites: researchers report that the insects detect ultrasonic clicks emitted by drought\u2011stressed plants and avoid laying eggs on them. The experiments, led by scientists at Tel Aviv University and published in eLife, showed females responded to airborne clicks in the 20\u201360 kHz band, with the moths&#8217; tympanic ears most sensitive near 38 kHz. Controlled trials using recorded plant sounds, live tomato plants and deafened moths demonstrated that the behavior depended on hearing and was integrated with olfactory cues. The finding reveals an acoustic dimension to plant\u2013insect interaction with possible ecological consequences for plant health and pest management.<\/p>\n<h2>Key takeaways<\/h2>\n<ul>\n<li>The focal insect is the Egyptian cotton leafworm moth, Spodoptera littoralis; females have tympanic ears sensitive to roughly 20\u201360 kHz, peaking near 38 kHz.<\/li>\n<li>Stressed plants (e.g., drought) emit airborne ultrasonic clicks; natural click rates in tomato patches are about 20 clicks per minute, experimental tests used 30\u201360 clicks\/min to simulate close proximity.<\/li>\n<li>In speaker-only arenas, moths preferred to lay eggs near speakers playing recorded plant stress clicks; this preference disappeared when moths were deafened, confirming an auditory mechanism.<\/li>\n<li>When real healthy and stressed plants were present, females avoided the stressed (clicking) plants, indicating integration of sound with visual\/olfactory cues.<\/li>\n<li>Electroantennogram recordings revealed distinct odor signals from drying versus hydrated plants, showing moths can combine smell and sound in site selection.<\/li>\n<li>Researchers used sound levels comparable to those measured from live plants, supporting ecological relevance of the responses.<\/li>\n<\/ul>\n<h2>Background<\/h2>\n<p>Plants communicate through multiple channels: volatile chemicals, root networks mediated by fungi, and\u2014as recent work suggests\u2014airborne ultrasonic vibrations. Chemical signaling, both above and below ground, is well documented: plants emit volatile organic compounds when damaged, which can prime defenses in neighbors, while mycorrhizal networks redistribute nutrients and distress cues. Acoustic emissions from plants were previously recorded but largely thought to be a physical by\u2011product of water stress rather than a biological signal intended for receivers.<\/p>\n<p>Insects perceive their environment through a mix of sensory modalities. Many moths have tympanic organs that detect ultrasonic pulses, usually studied in the context of bat echolocation or insect courtship. The hypothesis tested here was whether plant\u2011generated ultrasonics fall into that perceptual window and influence insect decisions, particularly female site selection for oviposition, which directly affects larval survival.<\/p>\n<h2>Main event<\/h2>\n<p>The research team ran a series of controlled laboratory experiments. In setups without plants, female moths showed a significant tendency to lay eggs near a speaker broadcasting recorded plant stress clicks. This attraction vanished when the moths were experimentally deafened, demonstrating that the response was auditory rather than driven by subtle air movements or other artifacts.<\/p>\n<p>When healthy plants were added to arenas and the recorded clicks were played near one of them, females favored the silent, non\u2011clicking plant. The outcome held across multiple click rates and spatial configurations, indicating that moths can interpret clicking as an indicator of plant condition and avoid stressed hosts for their offspring.<\/p>\n<p>The team also tracked movement: moths spent more time on the side of the arena producing plant clicks before making oviposition choices, suggesting an active evaluation rather than a simple reflex. Control tests showed female moths did not confuse male courtship sounds\u2014which fall in a similar frequency band\u2014for plant clicks; females did not prefer sites associated with male sounds for egg laying.<\/p>\n<p>Physiological assays complemented behavior. Electroantennogram recordings from moth antennae showed altered odor responses to drying versus hydrated plants, indicating that olfactory information differs with plant water status and is available to the insect alongside acoustic cues. Together, the data point to multimodal assessment when females select egg sites.<\/p>\n<h2>Analysis &#038; implications<\/h2>\n<p>This study extends the sensory ecology of plant\u2013insect interactions by demonstrating that airborne ultrasonic emissions from stressed plants can serve as informative cues for insects. For a female moth, choosing a healthy host increases larval prospects; avoiding drought\u2011stressed plants therefore likely provides a fitness advantage by reducing the chance of offspring encountering poor food quality or increased plant defenses.<\/p>\n<p>From an evolutionary perspective, the acoustic clicks may have originated as a physical consequence of cavitation or tissue desiccation during water loss. Whether selection has acted on plants or insects to accentuate or exploit these sounds remains unresolved, but the current data show insects can and do use the information. If widespread, acoustic cues could influence host selection across many herbivore taxa and alter plant\u2013herbivore dynamics in drought\u2011prone systems.<\/p>\n<p>Applied implications are notable: if pests avoid stressed hosts, agricultural management should consider how irrigation regimes influence pest distributions. Conversely, synthetic playback of plant stress sounds could be explored as a non\u2011chemical deterrent, though ecological side effects and long\u2011term efficacy would require careful field testing.<\/p>\n<p>At the ecosystem level, the finding raises questions about multi\u2011species networks: pollinators, predators and parasitoids might also detect plant acoustics, creating cascading effects. The integration of sound with established chemical signaling pathways suggests a richer communication landscape with both direct and indirect consequences for community structure.<\/p>\n<h2>Comparison &#038; data<\/h2>\n<figure>\n<table>\n<thead>\n<tr>\n<th>Measure<\/th>\n<th>Natural\/Measured<\/th>\n<th>Experimental setting<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Plant click rate (tomato patch)<\/td>\n<td>~20 clicks\/min<\/td>\n<td>30\u201360 clicks\/min (playback)<\/td>\n<\/tr>\n<tr>\n<td>Moth ear sensitivity<\/td>\n<td>20\u201360 kHz (peak \u2248 38 kHz)<\/td>\n<td>Playbacks centered on 20\u201360 kHz, levels matched to live plants<\/td>\n<\/tr>\n<tr>\n<td>Behavioral result<\/td>\n<td>Avoid stressed plants when live cues present<\/td>\n<td>Preference for speaker playing stress clicks in absence of plants<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/figure>\n<p>The table summarizes core empirical numbers: natural click rates measured in tomato patches, the frequency window of the moth tympanal organ, and the experimental playbacks used to approximate or slightly exceed natural click rates. The researchers matched playback amplitudes to field measurements to preserve ecological relevance while testing response thresholds under controlled conditions.<\/p>\n<h2>Reactions &#038; quotes<\/h2>\n<p>Tel Aviv University team members framed the study as the first demonstration that plant\u2011produced ultrasonics can influence animal choices. They positioned the work as opening a new sensory axis in plant\u2013animal ecology rather than closing a debate about origins or adaptive function.<\/p>\n<blockquote>\n<p>&#8220;We hypothesized that animals capable of hearing these high\u2011frequency sounds may respond to them and make decisions accordingly.&#8221;<\/p>\n<p><cite>Prof. Yossi Yovel, Tel Aviv University (study co\u2011author)<\/cite><\/p><\/blockquote>\n<p>The co\u2011authors emphasized the experimental chain of evidence\u2014behavioral preference, loss of preference when deafened, and concordant olfactory differences\u2014rather than asserting a definitive evolutionary narrative.<\/p>\n<blockquote>\n<p>&#8220;We assumed females seek an optimal site to lay their eggs \u2014 a healthy plant that can properly nourish the larvae \u2014 so we tested whether moths would heed a dehydration warning.&#8221;<\/p>\n<p><cite>Prof. Lilach Hadany, Tel Aviv University (co\u2011author)<\/cite><\/p><\/blockquote>\n<p>External experts asked for field replication before concluding broad ecological impact. Several ecologists noted the importance of testing other herbivores and of quantifying fitness outcomes for larvae in places with natural acoustic backgrounds.<\/p>\n<blockquote>\n<p>&#8220;This adds a plausible sensory channel to consider, but we need multispecies field data to assess population\u2011level effects.&#8221;<\/p>\n<p><cite>Independent ecologist (comment to authors)<\/cite><\/p><\/blockquote>\n<h2>\n<aside>\n<details>\n<summary>Explainer: plant ultrasonics and moth hearing<\/summary>\n<p>Ultrasonic plant emissions are brief, air\u2011borne clicks produced when internal tensions change\u2014often during cavitation events as xylem water columns break under drought. Many insects, including some moths, possess tympanic organs tuned to ultrasonic frequencies (above human hearing). Electroantennograms measure electrical responses of insect antennae to odorants, revealing differences in the chemical cues plants emit when hydrated versus drying. In behavioral assays, researchers combine these measures\u2014playback of recorded sounds, live plant presentations and sensory manipulations (e.g., deafening)\u2014to test which cues drive decisions such as oviposition.<\/p>\n<\/details>\n<\/aside>\n<\/h2>\n<h2>Unconfirmed<\/h2>\n<ul>\n<li>Whether plant clicks evolved as signals intentionally directed at other organisms or are purely a physical by\u2011product of stress is not resolved by the current data.<\/li>\n<li>It is unconfirmed how widespread sensitivity to plant ultrasonics is across herbivore, pollinator or predator taxa; broader surveys are needed.<\/li>\n<li>Direct field evidence that use of plant clicks changes long\u2011term population dynamics or crop damage levels remains to be demonstrated.<\/li>\n<\/ul>\n<h2>Bottom line<\/h2>\n<p>This study provides robust laboratory evidence that female Spodoptera littoralis can detect ultrasonic clicks from drought\u2011stressed plants and use those cues\u2014together with smell and sight\u2014to avoid laying eggs on stressed hosts. The experiments combined behavioral assays, auditory manipulation and antennal recordings to show multimodal assessment rather than reliance on a single cue.<\/p>\n<p>The broader implication is that acoustic emissions add a previously underappreciated channel to plant\u2013animal communication, with potential impacts on ecology and agriculture. However, field validation, multispecies surveys and fitness measurements are needed before translating the finding into pest\u2011management strategies.<\/p>\n<h2>Sources<\/h2>\n<ul>\n<li><a href=\"https:\/\/www.earth.com\/news\/insects-moths-listen-to-plants-talking-before-deciding-where-to-lay-their-eggs\/\" target=\"_blank\" rel=\"noopener\">Earth.com \u2014 news report summarizing the study (media)<\/a><\/li>\n<li><a href=\"https:\/\/elifesciences.org\" target=\"_blank\" rel=\"noopener\">eLife \u2014 peer\u2011reviewed journal (publisher; original study published in eLife)<\/a><\/li>\n<li><a href=\"https:\/\/www.tau.ac.il\" target=\"_blank\" rel=\"noopener\">Tel Aviv University \u2014 institutional page for research team (university\/official)<\/a><\/li>\n<\/ul>\n<\/article>\n","protected":false},"excerpt":{"rendered":"<p>Female Egyptian cotton leafworm moths (Spodoptera littoralis) use more than sight and smell when choosing egg sites: researchers report that the insects detect ultrasonic clicks emitted by drought\u2011stressed plants and avoid laying eggs on them. The experiments, led by scientists at Tel Aviv University and published in eLife, showed females responded to airborne clicks in &#8230; <a title=\"Moths &#8216;hear&#8217; stressed plants and avoid laying eggs, study finds\" class=\"read-more\" href=\"https:\/\/readtrends.com\/en\/moth-plant-ultrasound-egglaying\/\" aria-label=\"Read more about Moths &#8216;hear&#8217; stressed plants and avoid laying eggs, study finds\">Read more<\/a><\/p>\n","protected":false},"author":1,"featured_media":15088,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"rank_math_title":"Moths hear stressed plants and avoid laying eggs \u2014 Insight News","rank_math_description":"Tel Aviv University researchers show female Spodoptera littoralis detect ultrasonic clicks from drought\u2011stressed plants (20\u201360 kHz) and avoid laying eggs on them.","rank_math_focus_keyword":"moth, Spodoptera littoralis, plant ultrasound, egg-laying, plant stress","footnotes":""},"categories":[2],"tags":[],"class_list":["post-15092","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-top-stories"],"_links":{"self":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/posts\/15092","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/comments?post=15092"}],"version-history":[{"count":0,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/posts\/15092\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/media\/15088"}],"wp:attachment":[{"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/media?parent=15092"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/categories?post=15092"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/readtrends.com\/en\/wp-json\/wp\/v2\/tags?post=15092"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}