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Fish

Fish are aquatic vertebrates that are typically cold blooded, covered with scales, and equipped with two sets of paired fins and several unpaired fins. Fish are abundant in the sea and in freshwaters, with species being known from mountain streams (e.g., char and gudgeon) as well as in the deepest depths of the ocean (e.g., gulpers and anglerfish). Fish account for more than half of the known vertebrates. There are at least 24,600 known species of fish, of which over 23,000 are bony fish, with the remainder being about 850 sharks, rays, and chimeras and about 85 hagfishes and lampreys. They range in size from the 16 m (51 ft) whale shark to a 8 mm (just over 1/4 of an inch) long stout infantfish. They are of tremendous importance as food for people around the world, being either collected from the wild or being farmed in much the same way as cattle or chickens.

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Plants & Animals News

September 16, 2026

The flesh eating New World screwworm has returned to the United States, threatening livestock, wildlife, pets and potentially people as it spreads north. A new UC San Diego tracking system aims to predict where the parasite could strike next while ...
More than 60 years after surveys suggested a deep coral reef off Benin was probably dead, scientists have found it alive. Cameras revealed healthy-looking coral patches supporting multiple fish species more than 50 meters beneath the surface. The ...
Captive-raised saltwater crocodiles released into Bangladesh’s Sundarbans surprised scientists by settling into the wild rather than trying to return to their breeding facility. The result suggests that releasing larger, mature captive crocodiles ...
Scientists have engineered yeast to turn PET plastic and agricultural waste into ingredients for protein-rich, 3D-printed cookies called µBites. Developed partly for NASA’s Deep Space Food Challenge, the system can produce proteins, fats, ...
Long-lived bats appear to combine powerful immune defenses with unusual strategies for eliminating damaged cells, potentially helping them avoid cancer and disease for decades. Researchers hope these genetic tricks could eventually reveal new ways ...
Britain’s wasps have become mysteriously scarce this summer, and scientists suspect an unusual combination of temperature swings, heatwaves, and food shortages may be responsible. Even the wasps that remain appear unusually small, potentially ...
Insects quietly hold much of the natural world together, yet conservation efforts are overlooking the tropical regions where more than 80 percent of insect species live. Monash University researchers ...
Scientists have found evidence that some gut bacterial populations can spread rapidly between people and across continents, suggesting the microbiome may be more transmissible than previously thought. The research also revealed hidden bacterial ...
Researchers at UC San Diego have demonstrated that a key cellular enzyme can accurately read an eight-letter genetic alphabet, doubling the four letters used by all known life on Earth. Detailed imaging revealed that RNA polymerase handles synthetic ...
A substance found in edible sea squirts appeared to reverse several signs of aging in older mice. Plasmalogen supplements improved memory and learning, strengthened connections between brain cells, reduced inflammation, and even helped the mice grow ...
Puerto Rico’s normally rainy season has instead brought a severe and fast-growing drought. By August 25, three-quarters of the territory was in at least moderate drought, with extreme drought covering 44 percent and some areas receiving less than ...
MIT researchers have created bacterial “transistors” that can be wired together into living circuits capable of performing calculations and directing chemical signals. One day, these biological computers could coat plant roots or leaves, ...

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