Satellite images reveal ancient hunting traps used by South American social groups 

University of Exeter

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An illustration of a chacu, courtesy of Gerald Díaz-Vigil

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Credit: Gerald Díaz-Vigil

Satellite images have revealed an ancient system of elaborate, funnel-shaped mega traps likely built by hunters and pastoralists to catch prey in the high altitudes of northern Chile.

New research on the Andean landscape and the people who lived there has identified 76 stone ‘chacus’, often stretching hundreds of metres in length, that would have been used to capture vicuña, a wild relative of the alpaca.

Similar structures have been found in other arid regions of the world, including the Middle East, but this is the first time such a concentration has been discovered in the area, and it raises the possibility that they pre-date those known to have been used by the Inkas.

An archaeologist at the University of Exeter has also found evidence of settlements and outposts in the area known as the Western Valleys, establishing a high probability that it was home to foragers many centuries after it was believed people had adopted more settled agricultural social systems.

The study, by Dr Adrián Oyaneder, of Exeter’s Department of Archaeology and History, is published in the journal Antiquity, and is based on the research he conducted during his PhD.

“There has long been a discrepancy between what archaeological and ethnohistorical records have told us about life in the Western Valleys of northern Chile during the colonial period,” says Dr Oyaneder. “On the one hand, archaeological research has pointed to a gradual decline in hunting and gathering from 2,000 B.C. onwards with the introduction of domesticated plants and animals. But, historical sources, such as Spanish tax records from the 16th to the 19th centuries, refer to ‘Uru’ or ‘Uro’, which was a generic term for foraging populations who were of little economic interest to the colonisers.”

Using publicly available satellite data, Dr Oyaneder examined a 4,600 square-kilometre area of the Camarones River Basin, focusing on upland areas that had hitherto remained little studied. Over four months, he identified a huge number of new sites of archaeological interest.

Among them were 76 chacus, with the great majority being V-shaped traps formed by two ‘antennae’ built from dry-stone walls, around 1.5 metres in height and on average 150 metres in length. These funnelled down to an enclosure of around 95 square metres, which would have been dug or established to a depth of around two metres, sufficient to trap any animals driven into it by the hunters.

All the chacus were located on steep slopes, pointing downhill, with some employing natural topographical features to create one of the antennae. They were also at an altitude within the usual range of the vicuña.

“My reaction when I saw the first chacu was to double and even triple check it,” said Dr Oyaneder. “Initially, I thought it was a bit of a unique occurrence, but as I progressed with my survey, I realised that they were everywhere in the highlands and in a quantity never previously recorded in the Andes.

“And then when I began to read papers and books around the subject, particularly by Thérèse Bouysse-Cassagne and Olivia Harris, there was reference to the choquela, specialised vicuña hunting groups, and words referring specifically to chacu hunting people and chacu hunters.”

Dr Oyaneder identified almost 800 small-scale settlements, ranging from single buildings of no more than one square metre to groups of nine or more structures. These were plotted using GIS and grouped into likely clusters linked to nearby chacus and other settlements, all within a 5km distance.

“The picture that emerges is of a landscape occupied by a range of human groups from at least 6000 B.C. to the 18th century,” adds Dr Oyaneder. “These groups moved strategically across the highlands, tethered primarily to hunting resources, particularly vicuña. The evidence indicates overlapping lifeways, combining hunting-gathering with agropastoral practices, and a network of short-term seasonal settlements and outposts to help people move across rugged and difficult terrain.”

Dr Oyaneder is now conducting further research to date some of these sites and establish whether they represent the first examples of their kind in the Andean region.

A tethered hunting and mobility landscape in the Andean highlands of the Western Valleys, northern Chile is published in Antiquity and was funded by the Becas Chile-ANID doctoral scholarships programme and a FONDECYT project by the same agency, led by Dr Daniela Valenzuela (Universidad de Tarapacá).

Aerial photo of a double chacu

Credit

Dr Adrian Oyaneder

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Journal

Antiquity

DOI

10.15184/aqy.2025.10213 

Method of Research

Imaging analysis

Subject of Research

People

Article Title

A tethered hunting and mobility landscape in the Andean highlands of the Western Valleys, northern Chile

Article Publication Date

13-Oct-2025

 

New national standard to boost trust in edible bird’s nest industry

Duke-NUS Medical School

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Singapore has launched its first national standard to authenticate the quality of edible bird’s nest (EBN), a billion-dollar delicacy in Asia. The new standard strengthens consumer trust and levels the playing field for producers in a market long plagued by counterfeits and substitutes.

The new Singapore Standard (SS) 718 was jointly developed by the Duke-NUS Centre of Regulatory Excellence - Standards Development Organisation (CoRE-SDO) and Enterprise Singapore (EnterpriseSG), through the Singapore Standards Council (SSC). The standard leverages Near-Infrared (NIR) spectroscopy to provide an accurate, rapid, reproducible and non-destructive on-site method of authenticating EBN. NIR spectroscopy measures how infrared light is absorbed, reflected or transmitted by a material to extract information about the material. This contrasts against conventional methods of authentication, which require EBN producers to send samples to testing facilities and results in wastage.

The development and review of all Singapore Biomedical and Health Standards are coordinated through CoRE-SDO at Duke-NUS in partnership with EnterpriseSG, and follow a consensus-based process involving expert working groups, committee reviews, and public consultation.

The SS 718 has been developed from research involving Nanyang Polytechnic’s Standard Operating Procedure for the authentication of edible bird’s nest, which has previously demonstrated the efficacy of NIR spectroscopy in food authentication and safety.  

The standard provides recommendations on the minimum specifications of the portable NIR that should be used for the authentication, details the procedure to collect the NIR spectra, and provides the steps for data processing and assessment of the authenticity of the EBN sample.  

Through SS 718, EBN suppliers can leverage standardised, scientific methodology to authenticate their products and build trust in their brands. Emerging players will also be better equipped to establish themselves as credible producers and have a level playing field to grow their business. Ultimately, consumers stand to benefit from having access to more complete information, allowing them to make decisions with confidence.

Dr Henry Leung, Senior Specialist, Nanyang Polytechnic, who led the committee of experts in the drafting of the standard, said:

“Standardized testing methods like SS 718 are setting a new benchmark in EBN authentication, complementing existing gold-standard methods. This rapid, on-site solution enables faster decision-making when advanced analytical facilities are unavailable, thereby strengthening consumer trust and trade integrity. By adopting this innovation, Singapore positions itself as a strategic global hub for EBN trading, paving the way for international market expansion and supporting the modernization of the Traditional Chinese Medicine (TCM) industry with science-based, evidence-driven practices.”

Professor John Lim, Executive Director of the Centre of Regulatory Excellence at Duke-NUS said:

“This standard is more than a technical advance. It shows how Singapore can lead with science-based, practical solutions that safeguard consumers while giving the industry a competitive edge. By providing a fast and non-destructive way to authenticate edible bird’s nest, we are helping producers to minimise wastage and build trust in their brands, as well as giving consumers the confidence to make informed choices.”

Ms Choy Sauw Kook, Director-General (Quality and Excellence) at Enterprise Singapore, shared:

“The SS 718 underscores the vital role that standards play in ensuring quality assurance and driving business growth. Consumers can leverage this standard as an important tool to make informed choices about the products they select, while edible bird’s nest providers can use it to build credibility and trust in their brand. We remain committed to continue working closely with industry experts and stakeholders to develop new and relevant guidelines that enhance trust and safety, especially in the areas of health and food safety.”

SS 718 was developed by the Working Group on Authentication of Edible Bird’s Nest under the Singapore Standards Council, which comprises representatives from the Government, testing and certification bodies, educational and research institutions and industry stakeholders.

SS 718 can be purchased from the Singapore Standards e-shop.

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Method of Research

News article

 

The spy who came in from the WiFi: Beware of radio network surveillance!

New technology is able to infer the identity of individuals without a WiFi device on them through passively recording communication in radio networks – researchers warn of risks to privacy and call for protective measures

Karlsruher Institut für Technologie (KIT)

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“By observing the propagation of radio waves, we can create an image of the surroundings and of persons who are present,” says Professor Thorsten Strufe from KASTEL – KIT’s Institute of Information Security and Dependability. “This works similar to a normal camera, the difference being that in our case, radio waves instead of light waves are used for the recognition,” explains the cybersecurity expert. “Thus, it does not matter whether you carry a WiFi device on you or not.” Switching your device off does not help: “It’s sufficient that other WiFi devices in your surroundings are active.”

 

WiFi Routers as “Quiet Observers”

“This technology turns every router into a potential means for surveillance,” warns Julian Todt from KASTEL. “If you regularly pass by a café that operates a WiFi network, you could be identified there without noticing it and be recognized later – for example by public authorities or companies.” Felix Morsbach stresses that it is true that there are easier methods for secret services or cybercriminals to observe people right now – for example by accessing CCTV cameras or video doorbells. “However, the omnipresent wireless networks might become a nearly comprehensive surveillance infrastructure with one concerning property: they are invisible and raise no suspicion.” Actually, WiFi networks exist in almost all homes, offices, restaurants, and public spaces today.

 

No Special Hardware Require

Unlike attacks with LIDAR sensors or previous WiFi-based methods, which use channel state information (CSI) – i.e. measured data that indicate how a radio signal changes when it reflects off of walls, furniture, or persons – the attackers do not need any special hardware. This method requires nothing but a standard WiFi device. It works by exploiting the communication of legitimate users of the WLAN, whose devices are connected to the WiFi network. These regularly send feedback signals within the network, also called beamforming feedback information (BFI), to the router – in unencrypted form so that it is readable by anybody in range. This creates images from different perspectives that can serve to identify the respective persons. Once the underlying machine-learning model has been trained, the identification only takes a few seconds.

 

Almost 100% Accuracy – Technology Entails Risks to Privacy

 

In a study with 197 participants, the team could infer the identity of persons with almost 100% accuracy – independently of the perspective or their gait. “The technology is powerful, but at the same time entails risks to our fundamental rights, especially to privacy,” emphasizes Strufe. The researchers warn that this is particularly critical in authoritarian states where the technology might be used for the observation of protesters. Therefore, they urgently call for protective measures and privacy safeguards in the forthcoming IEEE 802.11bf WiFi standard.

 

Funding and Publication

The project was funded under the Helmholtz “Engineering Secure Systems” topic. The researchers will present their results at the “ACM Conference on Computer and Communications Security” (CCS) in Taipei. The paper will be available from October 13, 2025 at https://doi.org/10.1145/3719027.3765062.

 

Original publication

Todt, Julian; Morsbach, Felix; Strufe, Thorsten: BFId: Identity Inference Attacks utilizing Beamforming Feedback Information, ACM, 2025. DOI: 10.1145/3719027.3765062 (from October 13, 2025).

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Journal

ACM / IMS Journal of Data Science

DOI

10.1145/3719027.3765062 

Article Title

Todt, Julian; Morsbach, Felix; Strufe, Thorsten: BFId: Identity Inference Attacks utilizing Beamforming Feedback Information, ACM, 2025.

Article Publication Date

13-Oct-2025

 

When minds align: a neural basis for flocking

When animals move together in flocks, herds, or schools, neural dynamics in their brain become synchronized through shared ways of representing space, a new study by researchers from the University of Konstanz (Germany) suggests.

University of Konstanz

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Flocking animals, such as hundreds of birds sweeping across the sky in unison, are a mesmerizing sight. But how does their collective motion – seen in many species, from swarming locusts to schooling fish and flocking birds – arise?

Mohammad Salahshour and Iain Couzin from the Centre for the Advanced Study of Collective Behaviour (CASCB) at the University of Konstanz and the Max Planck Institute of Animal Behavior have developed a novel theoretical framework that integrates neurobiological principles to upend long-held assumptions about how flocking behaviour emerges in nature. In a recent article in Nature Communications they demonstrate that flocking does not require individuals to rely on rigid behavioural rules, as is typically assumed. Instead, it can arise naturally from a simple and widespread neural architecture found across the animal kingdom: the ring attractor network.

A paradigm shift in understanding collective motion
In the new model, flocking arises because neural activity in each animal becomes linked through perception: Every individual processes its surroundings using a ring attractor – a circular network of neurons that tracks the directions towards perceived objects in space. This way, the animal can maintain bearings towards others relative to stable features in the environment. The researchers found that when many such individuals interact, their neural dynamics synchronize, giving rise to spontaneous alignment and collective movement.

This means that coordinated motion can emerge directly from navigational processes in the brain, challenging decades of theory. Since the 1970s scientists believed that the mesmerizing, synchronized movements of animal groups resulted from individuals following behavioural “rules of thumb” – such as aligning with neighbours, avoiding collisions, and staying close. While these rules could replicate flock-like patterns in computer models, they failed to capture how real animals perceive and process their surroundings. The new framework shows that collective motion emerges when individuals represent the directions of others relative to stable features in their surroundings – a world-centred, or allocentric, perspective. This mechanism underlies what the authors describe as “allocentric flocking.”

One mechanism, a multitude of collective behaviours
Crucially, the ring attractor network does not just enable basic flocking, but it can generate a wide range of collective behaviours – from sudden expansions to smooth, coordinated turns. Empirical studies on fish and locust swarms responding, seemingly effortlessly, to their surroundings, support the ideas of the new model. “It’s an elegant solution,” says Salahshour. “Instead of needing a new set of rules for every behaviour, animals rely on a flexible, built-in system that creates complexity from simplicity.”

But animals need not rely on a single way of representing space. They can switch between an allocentric (world-centred) view – the one where bearings are encoded relative to stable features in the environment – and an egocentric (body-centred) view – where directions are represented relative to the animal’s own orientation, instead. In simulations of the new model, rapid switching between these two modes of representation improved coordination and stability, combining the advantages of both: the allocentric view supports global alignment, while the egocentric view enables individuals to respond to nearby neighbours and avoid collisions. “This flexibility is the secret to their adaptability,” explains Couzin. “The brain doesn’t choose one system over the other. It uses both to navigate the dynamics of a moving swarm.”

A wide range of implications – from social evolution to swarm robotics
The finding that complex group movements can emerge naturally from basic navigation skills already encoded in the brain’s ring attractor networks indicates that no specialized neuronal circuits are required. This further suggests that collective behaviours may have evolved easily from a universal neural mechanism already present in solitary ancestors. Allocentric flocking bridges the gap between brain and behaviour, revealing how individual cognition gives rise to collective intelligence and how order emerges from interaction – not only in animals, but potentially in future robotic and artificial systems.

By linking biological and artificial neural networks, the framework opens new possibilities for swarm robotics, for example, where robots could coordinate dynamically – without GPS or central control – by mimicking the brain’s dual navigation system. Furthermore, the framework is adaptable and allows the integration of features such as learning, collective sensing, and decision-making. More importantly, it provides a fresh perspective on collective motion, viewing it as the natural outcome of interacting minds sharing a common representation of space.

 

Key facts:

 

• Original publication: Mohammad Salahshour, Iain D. Couzin (2025) Allocentric Flocking. Nature Communications. DOI: https://doi.org/10.1038/s41467-025-64676-5
• Dr Mohammad Salahshour is a postdoctoral researcher in the Department of Collective Behaviour at the Max Planck Institute of Animal Behaviour and a member of the Konstanz-based Cluster of Excellence “Centre for the Advanced Study of Collective Behaviour”. His research focuses on evolutionary theory of collective behaviour.
• Professor Iain D. Couzin FRS is a Director of the Max Planck Institute of Animal Behavior as well as Chair of Biodiversity and Collective Behaviour at the University of Konstanz (Department of Biology). He is also Speaker of the Cluster of Excellence “Centre for the Advanced Study of Collective Behaviour”. His research centres on revealing the principles that underlie collective animal behaviour.
• The Max Planck Institute of Animal Behavior is a world-leading research institute dedicated to an integrative understanding of animal behaviour across all levels of organization. The Centre for the Advanced Study of Collective Behaviour at the University of Konstanz is an interdisciplinary Cluster of Excellence investigating the principles of collective behaviour in animals and other systems.
• Funding: German Research Foundation (DFG) under Germany’s Excellence Strategy, DFG Gottfried Wilhelm Leibniz Prize 2022 (I.D.C.), European Union’s Horizon 2020 Research and Innovation Programme, Path Finder European Innovation Council Work Programme, Office of Naval Research.

 

Note to editors:

A photo is available here:

https://www.uni-konstanz.de/fileadmin/pi/fileserver/2025_extra/when_minds_align.jpg

Caption: A flock of wild Snow Pigeons near Trongsa, Bhutan.

Copyright: Christian Ziegler

 

 

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Journal

Nature Communications

DOI

10.1038/s41467-025-64676-5 

Article Title

Allocentric Flocking