Reference Terms
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Animal shell
A shell is a hard, rigid outer layer, which has evolved in a very wide variety of different animals, including mollusks, sea urchins, crustaceans, turtles and tortoises, armadillos, etc. Scientific names for this type of structure include exoskeleton, test, carapace, and peltidium.
The shells that are perhaps most familiar and most commonly encountered, both in the wild and for sale as decorative objects, are seashells, more precisely, the external shells of marine mollusks. These are usually primarily composed of calcium carbonate, in the form of calcite or aragonite crystallised out in an organic matrix. Calcium carbonate in mollusc shells can take different crystalline forms, one being nacre otherwise known as mother of pearl.
Other kinds of animal shells are made from chitin, bone and cartilage, or silica.
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Plants & Animals News
November 11, 2025
Nov. 11, 2025 — Scientists at EPFL have unraveled the mystery behind why biological nanopores, tiny molecular holes used in both nature and biotechnology, sometimes behave unpredictably. By experimenting with engineered versions of the bacterial pore aerolysin, ...
Nov. 10, 2025 — Scientists have turned to advanced AI to decode the intricate ecosystem of gut bacteria and their chemical signals. Using a Bayesian neural network called VBayesMM, researchers can now identify genuine biological links rather than random ...
Nov. 9, 2025 — A Japanese-led research team has developed AUN, a groundbreaking immune-independent bacterial cancer therapy that uses two harmonized bacteria to destroy tumors even in patients with weakened immune systems. By leveraging the natural synergy between ...
Nov. 9, 2025 — Researchers from the University of Vienna discovered MISO bacteria that use iron minerals to oxidize toxic sulfide, creating energy and producing sulfate. This biological process reshapes how scientists understand global sulfur and iron cycles. By ...
Nov. 9, 2025 — In Death Valley’s relentless heat, Tidestromia oblongifolia doesn’t just survive—it thrives. Michigan State University scientists discovered that the plant can quickly adjust its photosynthetic machinery to endure extreme temperatures that ...
Nov. 8, 2025 — A revolutionary eDNA test detects endangered hammerhead sharks using genetic traces left in seawater, eliminating the need to capture or even see them. This powerful tool could finally uncover where these elusive species still survive, and help ...
Nov. 4, 2025 — Cockroach infestations don’t just bring creepy crawlers, they fill homes with allergens and bacterial toxins that can trigger asthma and allergies. NC State researchers found that larger infestations meant higher toxin levels, especially from ...
Nov. 4, 2025 — Researchers have, for the first time, estimated how quickly E. coli bacteria can spread between people — and one strain moves as fast as swine flu. Using genomic data from the UK and Norway, scientists modeled bacterial transmission rates and ...
Nov. 4, 2025 — When Surtsey erupted from the sea in 1963, it became a living experiment in how life begins anew. Decades later, scientists discovered that the plants colonizing this young island weren’t carried by the wind or floating on ocean currents, but ...
Nov. 4, 2025 — Beneath the ocean’s surface, bacteria have evolved specialized enzymes that can digest PET plastic, the material used in bottles and clothes. Researchers at KAUST discovered that a unique molecular signature distinguishes enzymes capable of ...
Nov. 4, 2025 — A collaboration between Brazilian and German researchers has led to a sunflower-based meat substitute that’s high in protein and minerals. The new ingredient, made from refined sunflower flour, delivers excellent nutritional value and a mild ...
Nov. 3, 2025 — Scientists uncovered how the amino acid leucine enhances mitochondrial efficiency by preserving crucial proteins that drive energy production. By downregulating the protein SEL1L, leucine prevents unnecessary degradation and strengthens the cell’s ...
Latest Headlines
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Nov. 11, 2025 — Japanese researchers uncovered a universal rule describing why life’s growth slows despite abundant nutrients. Their “global constraint principle” integrates classic biological laws to show ...
Nov. 9, 2025 — Deep beneath the ocean, scientists uncovered thriving microbial life in one of Earth’s harshest environments—an area with a pH of 12, where survival seems nearly impossible. Using lipid ...
Nov. 9, 2025 — NASA’s Cassini mission has revealed surprising heat flow at Enceladus’ north pole, showing the moon releases energy from both ends. This balance of heat could allow its subsurface ocean to remain ...
Nov. 5, 2025 — Researchers discovered fossil evidence showing that spionid worms, parasites of modern oysters, were already infecting bivalves 480 million years ago. High-resolution scans revealed their distinctive ...
Nov. 3, 2025 — Long ago, some saltwater fish adapted to freshwater — and in doing so, developed an extraordinary sense of hearing rivaling our own. By examining a 67-million-year-old fossil, researchers from UC ...
Nov. 3, 2025 — Okayama scientists have crafted a new wine grape, Muscat Shiragai, merging the wild Shiraga and Muscat of Alexandria. The variety is part of a larger collaboration between academia, industry, and ...
Nov. 3, 2025 — In the Gulf of California, a pod of orcas known as Moctezuma’s pod has developed a chillingly precise technique for hunting young great white sharks — flipping them upside down to paralyze and ...
Nov. 3, 2025 — Researchers at UC San Diego have figured out how to get bacteria to produce xanthommatin, the pigment that lets octopuses and squids camouflage. By linking the pigment’s production to bacterial ...
Nov. 3, 2025 — Penn State scientists uncovered an ancient bacterial defense where dormant viral DNA helps bacteria fight new viral threats. The enzyme PinQ flips bacterial genes to create protective proteins that ...
Nov. 2, 2025 — On the Canary Islands, scientists discovered that the spider Dysdera tilosensis has halved its genome size in just a few million years—defying traditional evolutionary theories that predict larger, ...