The Marsoulas Cave, between Haute-Garonne and Ariège, was the first decorated cave to be found in the Pyrenees. Discovered in 1897, the cave bears witness to the beginning of the Magdalenian (2) culture in this region, at the end of the Last Glacial Maximum. During an inventory of the material from the archaeological excavations, most of which is kept in the Muséum de Toulouse, scientists examined a large Charonia lampas (sea snail) shell, which had been largely overlooked when discovered in 1931.

The tip of the shell is broken, forming a 3.5 cm diameter opening. As this is the hardest part of the shell, the break is clearly not accidental. At the opposite end, the shell opening shows traces of retouching (cutting) and a tomography scan has revealed that one of the first coils is perforated. Finally, the shell has been decorated with a red pigment (hematite), characteristic of the Marsoulas Cave, which indicates its status as a symbolic object.

To confirm the hypothesis that this conch was used to produce sounds, scientists enlisted the help of a horn player, who managed to produce three sounds close to the notes C, C-sharp and D. As the opening was irregular and covered with an organic coating (3), the researchers assume that a mouthpiece was also attached, as is the case for more recent conches in collection of the Musée du quai Branly — Jacques Chirac. 3D impressions of the conch will enable this lead to be explored and verify whether it can be used to produce other notes.

The first carbon-14 dating of the cave, carried out on a piece of charcoal and a fragment of bear bone from the same archaeological level as the shell, provided a date of around 18,000 years. This makes the Marsoulas conch the oldest wind instrument of its type: to date, only flutes have been discovered in earlier European Upper Palaeolithic contexts; the conches found outside Europe are much more recent.

In addition to immersing us in the sounds produced by our Magdalenian ancestors, this shell reinforces the idea of exchanges between the Pyrenees and the Atlantic coast, more than 200 kilometres away.

Further information:

– Listen to the sound of the Marsoulas conch: https://soundcloud.com/cnrs_officiel/marsoulas-shell-conch-sound/s-234KE5bFZO1

– See the 3D model: https://sketchfab.com/3d-models/triton-700k-0bddff3405144c7b8f91f902e28bcc9b

Notes

(1) The laboratories involved are the Travaux et recherches archéologiques sur les cultures, les espaces et les sociétés (CNRS/Université Toulouse — Jean Jaurès/Ministère de la Culture), the Maison des sciences de l’homme et de la société de Toulouse (CNRS/Université Fédérale de Toulouse) and the Laboratoire d’archéologie moléculaire et structurale (CNRS/Sorbonne Université).

(2) Covering a period between around 21,000 and 14,000 years BP, it is characterised by worked animal bones and antlers and extensive exchange networks. The Altamira and Lascaux caves are the most famous examples.

(3) As the quantity is limited, analyses have not been able to identify its nature.

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The findings, which are published today in the journal Nature, may aid future efforts to understand why some embryos fail to form in the earliest stages of development, and lead to new clinical efforts in treating infertility or early miscarriages.

An embryo is fragile in the first hours after its formation. Rapid cell division and environmental stress make them prone to cellular errors, which in turn cause the sporadic death of embryonic stem cells. This is assumed to be one of the major causes of embryonic developmental failure before implantation.

Living organisms can remove cellular errors using immune cells which are dedicated to carry out this function, but a newly-formed embryo cannot create these specialised cells. To find out whether embryos can remove dying cells before the formation of an immune system, the researchers used high resolution time-lapse imaging technology to monitor zebrafish and mouse embryos, two established scientific models used to study vertebrate development.

They found that epithelial cells — which collectively form the first tissue on the surface of an embryo — can recognise, ingest and destroy defective cells. It is the first time this biological process, known as epithelial phagocytosis, has been shown to clear cellular errors in newly formed vertebrate embryos.

“Long before the formation of the organs, one of the first tasks performed by a developing embryo is to create a protective tissue,” says Dr. Esteban Hoijman, first and co-corresponding author of the paper.

According to Dr. Hoijman, epithelial phagocytosis was a surprisingly efficient process thanks to the presence of arm-like protrusions on the surface of epithelial cells. “The cells cooperate mechanically; like people distributing food around the dining table before tucking into their meal, we found that epithelial cells push defective cells towards other epithelial cells, speeding up the removal of dying cells,” he adds.

“Here we propose a new evolutionarily conserved function for epithelia as efficient scavengers of dying cells in the earliest stages of vertebrate embryogenesis,” says Dr. Verena Ruprecht, group Leader in the Cell & Developmental Biology program at the CRG and senior author of the paper. “Our work may have important clinical applications by one day leading to improved screening methods and embryo quality assessment standards used in fertility clinics.”

According to the authors, the discovery that embryos exhibit an immune response earlier than previously thought warrants further exploration on the role of mechanical cooperation as a physiological tissue function, which remains poorly understood, in other important biological processes such as homeostasis and tissue inflammation.

The study is published today in the journal Nature. The team was led by the CRG in Barcelona in collaboration with the Pompeu Fabra University (UPF) and the Institute of Photonic Sciences (ICFO), as well as the University Paris-Diderot.

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3D LiDAR can provide accurate imaging and mapping for many applications; it is the “eyes” for autonomous cars and is used in facial recognition software and by autonomous robots and drones. Accurate imaging is essential for machines to map and interact with the physical world but the size and costs of the technology currently needed has limited LIDAR’s use in commercial applications.

Now a team of researchers from Pointcloud Inc in San Francisco and the University of Southampton’s Optoelectronic Research Centre (ORC) have developed a new, integrated system, which uses silicon photonic components and CMOS electronic circuits in the same microchip. The prototype they have developed would be a low-cost solution and could pave the way to large volume production of low-cost, compact and high-performance 3D imaging cameras for use in robotics, autonomous navigation systems, mapping of building sites to increase safety and in healthcare.

Graham Reed, Professor of Silicon Photonics within the ORC said, “LIDAR has been promising a lot but has not always delivered on its potential in recent years because, although experts have recognised that integrated versions can scale down costs, the necessary performance has not been there. Until now.

“The silicon photonics system we have developed provides much higher accuracy at distance compared to other chip-based LIDAR systems to date, and most mechanical versions, showing that the much sought-after integrated system for LIDAR is viable.”

Remus Nicolaescu, CEO of Pointcloud Inc added, “The combination of high performance and low cost manufacturing, will accelerate existing applications in autonomy and augmented reality, as well as open new directions, such as industrial and consumer digital twin applications requiring high depth accuracy, or preventive healthcare through remote behavioural and vital signs monitoring requiring high velocity accuracy.

“The collaboration with the world class team at the ORC has been instrumental, and greatly accelerated the technology development.”

The latest tests of the prototype, published in the journal Nature, show that it has an accuracy of 3.1 millimetres at a distance of 75 metres.

Amongst the problems faced by previous integrated systems are the difficulties in providing a dense array of pixels that can be easily addressed; this has restricted them to fewer than 20 pixels whereas this new system is the first large-scale 2D coherent detector array consisting of 512 pixels. The research teams are now working to extend the pixels arrays and the beam steering technology to make the system even better suited to real-world applications and further improve performance.

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Gregariousness leads to better survival

Giraffe group formations are dynamic and change throughout the day, but adult females maintain many specific friendships over the long term. “Grouping with more females, called gregariousness, is correlated with better survival of female giraffes, even as group membership is frequently changing,” says Bond. “This aspect of giraffe sociability is even more important than attributes of their non-social environment such as vegetation and nearness to human settlements.”

The benefits of many friends

Aside from poaching, the main causes of adult female giraffe mortality are likely to be disease, stress or malnutrition, all of which are interconnected stressors. “Social relationships can improve foraging efficiency, and help manage intraspecific competition, predation, disease risk and psychosocial stress,” says UZH professor Barbara König, senior author of the study. Female giraffes may seek out and join together with an optimal number of other females in order to share and obtain information about the highest-quality food sources. Other benefits to living in larger groups might be lowering stress levels by reducing harassment from males, cooperating in caring for young, or simply experiencing physiological benefits by being around familiar females. The study also finds that females living closer to towns had lower survival rates, possibly due to poaching.

Social habits similar to humans and primates

The team documented the social behaviors of the wild free-ranging giraffes using network analysis algorithms similar to those used by big-data social media platforms. According to the results, the giraffes are surprisingly similar in their social habits to humans and other primates, for whom greater social connectedness offers more opportunities. Chimpanzees and gorillas, for example, live in communities where ties between many individuals facilitate the flexibility of feeding strategies. “It seems to be beneficial for female giraffes to connect with a greater number of others and develop a sense of larger community, but without a strong sense of exclusive subgroup affiliation,” adds Monica Bond.

Study of a giraffe population in Tanzania

For the past decade the research team has been conducting the largest study to date of a giraffe population. The vast scale of their study area in the Tarangire region of Tanzania spans more than a thousand square kilometers and includes multiple social communities, each with about 60 to 90 adult female members. Thus, the study was able to disentangle individual from community-level influences on survival. The study is also unique in combining social network analysis and modeling of vital rates such as survival in a sample of hundreds of individuals.

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“Although observations of an exoplanet’s atmospheric composition will be the first way to search for signatures of life beyond Earth, many aspects of a planet’s surface habitability are influenced by what’s happening beneath the planet’s surface, and that’s where Carnegie researcher’s longstanding expertise in the properties of rocky materials under extreme temperatures and pressures comes in,” explained Earth and Planets Laboratory Director Richard Carlson.

On Earth, the interior dynamics and structure of the silicate mantle and metallic core drive plate tectonics, and generate the geodynamo that powers our magnetic field and shields us from dangerous ionizing particles and cosmic rays. Life as we know it would be impossible without this protection. Similarly, the interior dynamics and structure of super-Earths will shape the surface conditions of the planet.

With exciting discoveries of a diversity of rocky exoplanets in recent decades, are much-more-massive super-Earths capable of creating conditions that are hospitable for life to arise and thrive?

Knowledge of what’s occurring beneath a super-Earth’s surface is crucial for determining whether or not a distant world is capable of hosting life. But the extreme conditions of super-Earth-mass planetary interiors challenge researchers’ ability to probe the material properties of the minerals likely to exist there.

That’s where lab-based mimicry comes in.

For decades, Carnegie researchers have been leaders at recreating the conditions of planetary interiors by putting small samples of material under immense pressures and high temperatures. But sometimes even these techniques reach their limitations.

“In order to build models that allow us to understand the interior dynamics and structure of super-Earths, we need to be able to take data from samples that approximate the conditions that would be found there, which could exceed 14 million times atmospheric pressure,” Fei explained. “However, we kept running up against limitations when it came to creating these conditions in the lab. “

A breakthrough occurred when the team — including Carnegie’s Asmaa Boujibar and Peter Driscoll, along with Christopher Seagle, Joshua Townsend, Chad McCoy, Luke Shulenburger, and Michael Furnish of Sandia National Laboratories — was granted access to the world’s most powerful, magnetically-driven pulsed power machine (Sandia’s Z Pulsed Power Facility) to directly shock a high-density sample of bridgmanite — a high-pressure magnesium silicate that is believed to be predominant in the mantles of rocky planets — in order to expose it to the extreme conditions relevant to the interior of super-Earths.

A series of hypervelocity shockwave experiments on representative super-Earth mantle material provided density and melting temperature measurements that will be fundamental for interpreting the observed masses and radii of super-Earths.

The researchers found that under pressures representative of super-Earth interiors, bridgmanite has a very high melting point, which would have important implications for interior dynamics. Under certain thermal evolutionary scenarios, they say, massive rocky planets might have a thermally driven geodynamo early in their evolution, then lose it for billions of years when cooling slows down. A sustained geodynamo could eventually be re-started by the movement of lighter elements through inner core crystallization.

“The ability to make these measurements is crucial to developing reliable models of the internal structure of super-Earths up to eight times our planet’s mass,” Fei added. “These results will make a profound impact on our ability to interpret observational data.”

The project is partially supported by a Carnegie Venture Grant and the U.S. National Science Foundation.

The project is made possible by the Z Fundamental Science Program.