ARACHNOLOGY

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

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

PLOS

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Argiope bruennichi.

view more 

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 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

  

New algorithm lets autonomous drones work together to transport heavy, changing payloads

Scientists at TU Delft in The Netherlands have developed a new algorithm that allows multiple autonomous drones to work together to control and transport heavy payloads, even in windy conditions

Delft University of Technology

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Three drones carry a load together, using the new algorithm developed at TU Delft, The Netherlands

view more 

Credit: Sihao Sun

Scientists at TU Delft, The Netherlands, have developed a new algorithm that allows multiple autonomous drones to work together to control and transport heavy payloads, even in windy conditions. Ideal for reaching and maintaining hard-to-reach infrastructure, like offshore wind turbines. With often harsh weather, limited payload capacity and unpredictable contact with the environment, it is difficult for current drones to operate safely and effectively. The results have been published in Science Robotics.

“A single drone can only carry a very limited load,” explains Sihao Sun, robotics researcher at TU Delft. “This makes it hard to use drones for tasks like delivering heavy building materials to remote areas, transporting large- amount of crops in mountainous regions, or assisting in rescue missions.”

To overcome these limitations, the TU Delft team designed a system where multiple drones are connected to a payload via cables, thereby carrying much heavier loads. By adjusting their positions in real time, the drones can not only lift and transport the heavy object but also control its orientation, which is crucial for precise placement in complex environments.

Fast coordination

“The real challenge is the coordination,” says Sun. “When drones are physically connected, they have to respond to each other and to external disturbances like sudden movements of the payload in rapid motions. Traditional control algorithms are simply too slow and rigid for that.”

The new algorithm developed by the team is fast, flexible, and robust. It adapts to changing payloads and compensates for external forces without requiring sensors on the payload itself, which is an important advantage in real-world scenarios.

Basketball obstacle course in the lab

“We built our own quadrotors and tested them in a controlled lab environment,” Sun shares. “We used up to four drones at once, added obstacles, simulated wind with a fan, and even used a moving payload like a basketball to test dynamic responses.” The system passed all tests. And because the drones are autonomous, they only need to be given a destination. They navigate independently, adjusting for obstacles and disturbances along the way. “You just tell them where to go, and they figure out the rest”, Sun adds.

Preparing for real-world applications

Currently, the system uses external motion capture cameras for indoor testing, and is therefore not useful in outdoor environments yet. The team hopes to prepare the technology for real-world deployment in the future, with potential applications in search and rescue, agriculture, and remote construction

New algorithm lets autonomous drones work together [VIDEO] 

---

Journal

Science Robotics

DOI

10.1126/scirobotics.adu8015 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Agile and Cooperative Aerial Manipulation of a Cable-Suspended Load

Article Publication Date

29-Oct-2025

Drones could cut travel delays and reduce spoilage of donated blood, new Concordia study shows

Researchers integrated the technology with mobile donation vehicles to create a flexible and time-sensitive collection system

Peer-Reviewed Publication

Concordia University

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Amirhossein Abbaszadeh: “Vehicle routing problems are not new to operations research, but the perishability of blood brings a time-sensitive challenge that changes how routes must be planned,”

view more 

Credit: Concordia University

Delivering blood from collection sites to labs is a fast-paced, labour-intensive process. Donated blood can deteriorate within a few hours at room temperature, leaving little room to manoeuvre in case of unexpected traffic congestion or other delays between collection sites and blood centres.

But if you can’t get through traffic, you can go over it, thanks to drone technology.

In a study published in the journal Computers & Operations Research, Concordia PhD candidate Amirhossein Abbaszadeh and Hossein Hashemi Doulabi, an associate professor in the Department of Mechanical, Industrial and Aerospace Engineering, present a new optimization model that uses drones to support mobile blood donation vehicles (“bloodmobiles”). The model offers a faster, more efficient and more reliable way to transport donated blood in cities.

Powered by smart logistics

The researchers’ Drone-Aided Mobile Blood Collection Problem is the first integrated framework that coordinates the movements of both bloodmobiles and drones to preserve blood freshness and improve overall system performance.

At its heart is a smart logistics system where bloodmobiles travel to multiple collection sites while drones shuttle between them and a central blood centre. This method eliminates delays caused by traffic and ensures that freshly donated blood reaches the blood centre quickly for processing into its components — such as platelets, which must be separated within six hours.

The researchers achieved this by developing a mixed-integer linear programming model that synchronizes the routes, schedules and collection activities of both bloodmobiles and drones. Because such a large-scale optimization problem is computationally demanding, the team also designed a rolling-horizon-based matheuristic algorithm. This type of algorithm breaks the problem into smaller, more manageable parts, solving sequentially while simultaneously exploring nearby alternatives to find better ones.

“Vehicle routing problems are not new to operations research, but the perishability of blood brings a time-sensitive challenge that changes how routes must be planned,” says Abbaszadeh. “That’s when I thought of using drones.”

Unlike previous studies that treated bloodmobiles and drones as separate systems, this work fully integrates their operations. Drones can take off from, land on or travel aboard bloodmobiles, allowing flexible coordination across multiple collection points without fixed infrastructure.

The model also considers the age of the blood — the time elapsed since donation — as a key optimization factor, rewarding fresher blood deliveries to ensure quality.

Putting the model to the test

The researchers used Quebec City as a real-world case study to test their model. They identified 13 potential collection sites, estimated the number of potential donors at each site and calculated the distance to the nearest blood centre.

“We used Google Maps to calculate the road distance and the most direct flight path since drones don’t need to use roads,” explains Abbaszadeh.

“We performed several analyses using different parameters: What if we used drones that had more load capacity, higher battery capacity or moved at higher speeds? We then compared the drone-aided system to the bloodmobile-only system.”

They found that adding drones to the blood collection fleet significantly reduced transport times. It also increased hourly delivery rates and maintained better consistency in blood freshness.

The authors write that their findings demonstrate the real potential of drone-assisted logistics in healthcare supply chains, particularly in time-critical operations like blood collection. They add that their framework could be adapted to other humanitarian or medical delivery contexts where speed, coordination and freshness are essential.

Read the cited paper: “Drone-Aided Mobile Blood Collection Problem”

---

Journal

Computers & Operations Research

DOI

10.1016/j.cor.2025.107253 

Method of Research

Computational simulation/modeling

Subject of Research

People

Article Title

Drone-aided mobile blood collection problem: A rolling-horizon-based matheuristic

 

Researchers uncover oldest 3D burrow systems in Hubei's Shibantan Biota

Chinese Academy of Sciences Headquarters

FacebookXLinkedInWeChatBlueskyMessageWhatsAppEmail

 

image: 

Treptichnus in the Shibantan assemblage in the Wuhe area.

view more 

Credit: Image by NIGPAS.

A research team from the Nanjing Institute of Geology and Palaeontology of the Chinese Academy of Sciences (NIGPAS) has made progress in studying the Shibantan Biota in Yichang, Hubei Province, uncovering the oldest known complex three-dimensional burrow systems to date. Preserved in approximately 550-million-year-old strata, these trace fossils show that complex animal behaviors were modifying the seafloor environment nearly 10 million years earlier than previously thought.

The Ediacaran–Cambrian transition, around 539 million years ago, marks one of the most significant ecosystem revolutions in Earth's history. A key driver of this ecological shift was the transition of metazoan behavior from simple two-dimensional surface activities to three-dimensional exploration deep into sediments. This "substrate revolution" transformed the seafloor from a uniform, matground-dominated system into a heterogeneously, bioturbated modern-style seabed, permanently altering the trajectory of Earth's environmental and biological evolution.

The researchers conducted a systematic study of trace fossils from the Shibantan Biota (approximately 550–543 million years old). They identified multiple ichnospecies within the genus Treptichnus and established a new ichnospecies, Treptichnus streptosus. By combining these findings with previously discovered three-dimensional trace fossils such as Lamonte and tadpole-shaped traces from the same biota, the study offers an in-depth analysis of the evolutionary and ecological significance of the emergence of animals' vertical exploration behavior.

The findings, published in Science Advances on Oct. 29, reveal that complex animal behaviors emerged on the eve of the Cambrian explosion.

Treptichnus is a landmark trace fossil, representing the first "3D exploration" of sediments by animals, and holds importance in evolutionary biology, animal behavior, and ecology. The first appearance of T. pedum, a member of this genus, formally defines the Ediacaran–Cambrian boundary. The new discovery from the Shibantan Biota predates this revolutionary behavior. In addition to reporting the new species T. streptosus, the study identifies other ichnospecies including T. cf. bifurcus, T. rectangularis, and T. pollardi, demonstrating that animal burrowing behaviors had already achieved considerable diversity by this period.

Furthermore, the Shibantan Biota preserves other three-dimensional burrows, such as Lamonte and tadpole-shaped traces. The concentrated occurrence of these vertical exploration behaviors reflects early sedimentary ecological stratification and complex foraging strategies, indicating a gradually enhanced ability of trace-making organisms to engineer substrates.

The study found that Lamonte caused intensive bioturbation within the Shibantan Biota. This not only disrupted microbial mats on the sediment surface but also dismantled the ecological environment of Ediacara-type organisms that depended on these mats. This suggests bioturbation may have been a contributing factor to the first extinction event of the Ediacara biota around 550 million years ago.

The emergence of these complex behaviors and their cumulative ecological effects intensified toward the end of the Ediacaran Period. This led to the gradual decline of microbial mats, continuously eroding the ecological foundation of Ediacara-type organisms while creating new ecological opportunities for the diversification of other metazoans. Driven by the synergy of various biological and non-biological factors, this process ultimately contributed to the profound ecosystem transformation during the Ediacaran–Cambrian transition.

This research further confirms that the rich and diverse assemblage of trace fossils and body fossils preserved in the Shibantan Biota provides a window for studying major ecosystem changes at the transition between the Precambrian and Phanerozoic Eons.

This work was supported by the National Natural Science Foundation of China.

---

Journal

Science Advances

DOI

10.1126/sciadv.adx9449