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Wednesday, October 29, 2025

ARACHNOLOGY

Spider web “decorations” may help pinpoint location of captured prey

New findings could inspire innovation in spider web-mimicking synthetic materials

PLOS

The effect of different structural decoration geometries on vibration propagation in spider orb webs — image:
*Argiope bruennichi.*
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Credit: Pierluigi Rizzo (member of Aracnofilia - Italian Society of Arachnology), CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

The long-standing mystery around why spider webs sometimes feature “extra touches” known as stabilimenta has been revisited in a new study which suggests that their wave-propagation effects could help spiders locate captured prey. Gabriele Greco of the Swedish University of Agricultural Sciences and colleagues present these findings in the open-access journal PLOS One on October 29, 2025.

Many spider species build spiral wheel-shaped webs—orb webs—to capture flying prey, and many can incorporate stabilimenta into the web structure. These “decorations” may look like zig-zagging threads spanning the gap between two adjacent “spokes,” or threads arranged in a circular “platform” around the web center. The purpose of stabilimenta is unclear; proposed functions include water collection, body temperature regulation, and balancing insect attraction with deterrence of predatory wasps or birds.

Another possibility is that stabilimenta aid spiders by influencing the propagation of web vibrations triggered by the impact of captured prey. However, until now, no studies had explored this idea. To address the gap, Greco and colleagues observed different stabilimentum geometries constructed by wasp spiders, Argiope bruennichi. Based on these structures, the researchers then ran numerical simulations to explore how stabilimenta affect prey impact vibrations.

In the simulations, the presence or absence of stabilimenta affected web vibrations differently, depending on the angle of the waves generated by prey impact. For waves generated at angles perpendicular to the web surface or perpendicular to the threads spiraling out from the web center, stabilimenta caused negligible delays in wave propagation.

However, for waves generated in the same direction as the spiral threads, vibrations in webs with stabilimenta propagated to a greater number of potential detection points across the web—where a spider might sense them—than in webs without stabilimenta. This suggests that stabilimenta may boost a spider’s ability to pinpoint the location of prey caught in its web.

While these findings deepen understanding of stabilimenta, the authors note that their real-world impact on prey localization may be limited, with other functions having greater effects. However, they say, this study could inform the design of web-inspired synthetic materials with finely tuned wave-propagation abilities.

The authors add: “This study reveals that the decorative stabilimentum in Argiope bruennichi webs is more than just ornament, for it subtly changes how certain vibrations travel through the web. By combining field observations and simulations, the work discusses the mechanical role for stabilimenta and inspires designs for bio-inspired materials with tunable elastic properties.”

The effect of different structural decoration geometries on vibration propagation in spider orb webs

The stabilimentum in Argiope bruennichi. a) The production of aciniform silk by A. bruennichi when wrapping a prey. b) A juvenile A. bruennichi in the centre of its web with the stabilimentum (courtesy of Letizia Alleruzzo, Aracnofilia – Italian Association of Arachnology). c– h) The different types of stabilimentum observed in the webs: normal (N), juvenile (J), reduced (R), platform (P), drafted (D), and absent (A, i.e., without stabilimentum).

Credit

Greco et al., 2025, PLOS One, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)

In your coverage, please use this URL to provide access to the freely available article in PLOS One: http://plos.io/47eT9dH

Citation: Greco G, Dal Poggetto VF, Lenzini L, Castellucci F, Pugno NM (2025) The effect of different structural decoration geometries on vibration propagation in spider orb webs. PLoS One 20(10): e0332593. https://doi.org/10.1371/journal.pone.0332593

Author countries: Sweden, Italy, Denmark, U.K.

Funding: G.G. was supported by the project “EPASS” under the HORIZON TMA Marie Skłodowska-Curie Actions Postdoctoral Fellowships - European Fellowships (project number 101103616). G.G., L.L. and F.C. were also supported by Aracnofilia – Italian Association of Arachnology. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Journal

PLOS One

DOI

10.1371/journal.pone.0332593

Method of Research

Observational study

Subject of Research

Animals

Article Title

The effect of different structural decoration geometries on vibration propagation in spider orb webs

Article Publication Date

29-Oct-2025

Sunday, February 15, 2026

ARACHNOLOGY

Scientists show how to predict world’s deadly scorpion hotspots

International research team pinpoints high-risk areas to inform global scorpion sting prevention

University of Galway

image:
A Giant Asian forest scorpion (Heterometrus sp.)
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Credit: Andrew Downes, Xposure

An international team of scientists have identified how to pinpoint and predict hotspots for some of the most dangerous species of scorpion in the world.

The researchers have established the key environmental conditions that determine where lethal, venomous arachnids thrive - findings that could help shine a light on flashpoints for scorpion stings in tropical regions across the globe.

The team of scientists used field observations in Africa combined with computer modelling to predict where dangerous scorpion species are most likely to be found and what factors influence their distributions.

Their analysis uncovered a striking pattern - soil type largely determines where most scorpions live, while temperature, both average and seasonal ranges, play a key role for some species.

Crucially, not all scorpions behave alike. Some are adaptable and widespread, while several others showed extremely restricted predicted distributions, suggesting narrow habitat requirements and localised risk zones.

The research was conducted by an international team from University of Galway, in partnership with University Ibn Zohr in Morocco.

The findings of the study are published in Environmental Research Communications. It focuses on central Morocco, one of the most severe global hotspots for scorpion stings, and aims to guide prevention strategies, as well as the development of new diagnostic tools and antivenoms.

Dr Michel Dugon, Head of the Venom Systems Lab at University of Galway and senior author of the study, said: “The findings could save lives. By pinpointing where dangerous scorpions are most likely to appear, health authorities can target awareness campaigns, train frontline medical staff, and focus community prevention in high-risk areas, especially protecting children. The approach can be applied wherever scorpions pose a threat, from Brazil to the Middle East and India.”

Scorpion stings are a hidden global public health crisis, particularly across tropical and subtropical regions. Every year, more than 2 million people are stung. While most stings cause pain and swelling, some species can deliver venom that leads to very severe illness and death, especially in children and older people. Globally, scorpion stings are estimated to claim the lives of more than 3,000 children annually.

While antivenoms exist for a range of scorpion species, medical teams often struggle to identify which species is responsible, making timely, effective treatment difficult.

To address this issue, the researchers used a computer-mapping tool called Maximum Entropy to predict where dangerous scorpions live and what environmental conditions they prefer.

The analysis uncovered the striking patterns. Using globally available data on soil, temperature, and other habitat factors, the scientist demonstrates a way to pinpoint high-risk scorpion areas outside Morocco, including regions of the tropics where detailed species records are limited.

The research was carried out by established and doctoral scientists from both universities, with support from University of Galway undergraduate students who travel to Morocco annually as part of their Bachelor of Science Zoology programme.

Dr Dugon added: “Overall, we know very little about the ecology of scorpions, their venom and the best way to treat scorpion stings. Our international collaborative efforts aim to develop new tools for the prevention, diagnostic and treatment of scorpion stings globally. This requires multidisciplinary teams including public health specialists, clinicians, zoologists and members of local communities.”

Fouad Salhi, doctoral researcher at the University Ibn Zohr of Agadir and first author of the study, said: “This research shows how biodiversity data can inform public health policies. By combining long-term fieldwork with ecological modelling, we were able to identify where dangerous scorpions are most likely to occur. We aim to have real-world impact — supporting prevention strategies, improving medical preparedness, and ultimately contribute to the reduction of the burden of scorpion stings, both in Morocco and beyond.”

Dr Colin Lawton, Head of Zoology at University of Galway and co-author of the study, said: “University of Galway is gaining momentum as a centre of excellence in zoological research, addressing questions of global importance, from fish stock to mammal conservation and animal-borne disease mitigation. We are very proud to integrate our BSc Zoology students into our research activities and international partnerships.”

The full study in Environmental Research Communications is available at https://iopscience.iop.org/article/10.1088/2515-7620/ae3fef.

Ends

A golden Moroccan scorpion (Buthus sp.)