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Reference Terms
from Wikipedia, the free encyclopedia

Circadian rhythm

A circadian rhythm is a roughly 24 hour cycle in the physiological processes of living beings, including plants, animals, fungi and cyanobacteria.

In a strict sense, circadian rhythms are endogenously generated, although they can be modulated by external cues such as sunlight and temperature. Circadian rhythms are important in determining the sleeping and feeding patterns of all animals, including human beings. There are clear patterns of brain wave activity, hormone production, cell regeneration and other biological activities linked to this daily cycle.

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Plants & Animals News

September 9, 2026

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, ...
Morning glories may be getting caught in an evolutionary tug-of-war between surviving climate change and attracting increasingly scarce pollinators. Over just nine years, researchers found that the plants’ rate of adaptation plunged by 96%, even ...
Scientists discovered that more than 500 species of vesper bats possess two separate sets of antibody genes, an immune arrangement never before found in mammals. The surprising system could help explain how bats tolerate so many viruses without ...
Researchers have produced a form of Spirulina containing biologically active vitamin B12 at levels comparable to beef. By carefully controlling the light used to grow the algae, they overcame a major problem with conventional Spirulina, which mainly ...
Dogs and humans may have more in common when it comes to aging than scientists realized. Researchers with the Dog Aging Project found that patterns of small molecules in dogs’ blood were linked to longer or shorter lifespans in remarkably similar ...
Every one of 212 plant-based meat alternatives and drinks tested in the UK contained at least one naturally occurring fungal toxin, though concentrations remained below recommended EU guideline ...
DNA from a nearly 190-year-old museum specimen has helped scientists confirm a distinct Himalayan pangolin species hiding in plain sight in Nepal and northern India. The discovery could give conservationists a powerful new way to trace illegally ...

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