Fascinating scientific shots

A school for sentinels. In the village of Aghien-Télégraphe, near Abidjan, Côte d'Ivoire, a teacher is telling schoolchildren about their future role in a participatory monitoring project aimed at protecting a nearby freshwater lagoon. They will act as sentinels to prevent the proliferation of cyanobacteria, which are easily identifiable by the green colour they give to water.

The Scream. This natural version of Edvard Munch’s famous painting, The Scream, is in fact a structure built by bryozoans, tiny animals less than a millimetre in size that have calcium carbonate skeletons and are found in colonies in cold waters. Each organism lives in a sort of calcium carbonate chamber with openings, the main one of which enables it to filter seawater and feed.

Ice melt. These tiny blocks of ice apparently adrift on the ocean are in fact crystals of metal-organic frameworks (MOF), nanostructured materials renowned for their exceptional porosity. They will grow and then combine with their neighbours to produce a smooth, homogeneous layer, free of cracks. The membrane thus formed will filter gases for various applications or catalyse chemical reactions.

Superpredation. The fearsome reputation of praying mantises is well established… Sadly for its prey, a young common wall gecko (Tarentola mauritanica) photographed in the Massif des Maures, in southeastern France. While intraguild predation (or superpredation) is commonplace, arthropod predation of vertebrates is only rarely observed.

Sampling at sunset. During the southern summer, the sun never sets on the Weddell Sea in Antarctica. It simply sinks to the horizon, casting a golden-red glow over the frozen ocean. Aboard the South African research vessel, SA Agulhas II, scientists carry out oceanographic sampling in order to study the effects of global warming on this remote part of the Southern Ocean.

Tongue galaxy. The tongue has not yet revealed all its secrets to scientists who are trying to understand what happens in the event of an infection or a loss of taste. The small spikes (blue autofluorescence) are filiform papillae which play a mechanical role, while the two circular galaxy-like areas (top right and bottom left) are taste buds able to perceive tastes.

Dancing in the twilight. Introducing Euphysetta lucani, a star ballet dancer in the Rhizaria company! Normally found in the depths of the ocean, this specimen measuring a mere 250 micrometres was seen floating near the surface in the North Atlantic. This protist extracts silicon from the oceans in order to build its tiny glass skeleton.

A more intuitive prosthesis. The paralympic athlete Christophe Huchet was the pilot of the French Smart ArM team during the Cybathlon 2020 international competition. His collaboration with scientists has given rise to new control algorithms that enable those who had a limb amputated above the elbow to make more intuitive use of their prosthesis.

Prawn in the moonlight. Rediscovered in the collections of the MNHN French national museum of natural history, this specimen of Aeger insignis lived in a lagoon in the Late Jurassic around 140 million years ago. This prawn belonged to an extinct family that had highly developed jawfeet, which the animal could use as “rakes” to search for food in the sediment.

Cosmic Dust. This cosmic dust grain, collected in central Antarctica near the French-Italian Concordia Station, is one of some 5 200 tonnes of micrometeorites from comets or asteroids that reach the Earth's surface every year. The “spherule” shown here has a diameter of 170 micrometres.

A cellular Van Gogh. These microscopic whorls reminiscent of Van Gogh's painting, The Starry Night, are actually formed by the fusion of muscle precursor cells. Their cell nuclei can be seen in cyan, the actin cytoskeleton in blue, and, in yellow, a protein indicating the formation of new muscle fibres.

A fly, a corpse, a resurrection. Listed as extinct since 1836, the bone skipper (Thyreophora cynophila) was rediscovered in the French Pyrenees in 2019. Only found in winter, and exclusively on the corpses of large mammals, this distinctive fly is now being studied by researchers with the help of citizen scientists.

Learning to see. For PR2, an autonomous service robot, finding its way around an unfamiliar environment is certainly a complex task, yet by no means impossible! Using the 3D camera located on its “head” and its optical motion capture system, PR2 can sense its surroundings and learn to see what it can move, lift or press using its gripper. Interaction upon interaction, the robot's learning algorithm enables it to use its skills to build its own view of the world.

Unicellular maze. More than 40 million years ago, this 2 mm-long alveolinid specimen collected in the Paris Basin belonged to the Foraminifera family, single-celled marine organisms that inhabited marine or brackish environments, in both warm and cold waters. This fossil provides valuable clues for reconstructing past climates. When observed under X-rays, it reveals a complex internal organisation, with hundreds of tiny chambers, known as chamberlets, arranged in a spiral.

Will you be my Valentine? Where on earth did scientists find this tiny blue smiley face with a heart-shaped mouth? The answer is in the cells that line the inside of vessels. It is in fact a protein called SAM68. While it seems to be grinning, the research around it is nothing to laugh about: it aims to elucidate how a tumour triggers the creation of new blood vessels to feed and proliferate.

An eye in the rock. The image shows a bird’s eye view of one of the galleries of the Grotte de la Madeleine cave, in the Gorges de l'Ardèche in southern France. This was entirely scanned using ground-based lidar, or 3D-laser scanning, which makes it possible to “see” from the outside and thus identify features formed in the past. This technology provides an unprecedented overhead view – or nadir view – of the ceiling of the gallery and its astonishing formations, testifying to the erosion that created these imposing shapes several million years ago.

Birth of a canyon. Although this landscape has only just been created, there is nothing new about it. In fact, this is a numerical model of the ecosystem of the Bright Angel Trail, a hiking path located in Grand Canyon National Park, Arizona (US). The system deployed here can reconstruct a landscape by automatically selecting various plant and animal species and placing them in the most suitable location. Used in palaeontology, this tool makes it possible to model and test ecosystems that are no longer accessible.

The spaghetti incident. Throughout their use, materials are exposed to mechanical and thermal stress, which deforms and damages them. This micrometre-scale image, produced by digital modelling, shows a sample of copper that has cracked. A microstructure of dislocations – here seen resembling tangled spaghetti – was formed by the opening of the crack.