Fuel subsidies defy green trend amid rising climate alarm

Even as warnings of climate catastrophe and calls for greener economies grow ever louder, the world is still spending hundreds of billions of dollars every year to subsidise the fossil fuels that are causing the planet to ...

Dirty data: Firms count environmental costs of digital planet

Technology is often touted as a solution to the world's environmental challenges, but it is also part of the problem: industry executives are facing rising pressure to clean up their energy and resource-intensive business.

Electric car switch on for health benefits

Could the health benefits and reduced costs to healthcare systems be enough to justify subsidizing charging infrastructure to allow society to switch from the internal combustion engine to electric vehicles faster than current ...

Scientists unearth 'most bird-like' dinosaur ever found

Researchers in Germany have unearthed a new species of flying dinosaur that flapped its wings like a raven and could hold vital clues as to how modern-day birds evolved from their reptilian ancestors.

415.26 parts per million: CO2 levels hit historic high

Scientists in the United States have detected the highest levels of planet-warming carbon dioxide in Earth's atmosphere since records began, sounding new alarm over the relentless rise of man-made greenhouse gas emissions.

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Fossil

Fossils (from Latin fossus, literally "having been dug up") are the preserved remains or traces of animals, plants, and other organisms from the remote past. The totality of fossils, both discovered and undiscovered, and their placement in fossiliferous (fossil-containing) rock formations and sedimentary layers (strata) is known as the fossil record. The study of fossils across geological time, how they were formed, and the evolutionary relationships between taxa (phylogeny) are some of the most important functions of the science of paleontology. Such a preserved specimen is called a "fossil" if it is older than some minimum age, most often the arbitrary date of 10,000 years ago. Hence, fossils range in age from the youngest at the start of the Holocene Epoch to the oldest from the Archaean Eon several billion years old. The observations that certain fossils were associated with certain rock strata led early geologists to recognize a geological timescale in the 19th century. The development of radiometric dating techniques in the early 20th century allowed geologists to determine the numerical or "absolute" age of the various strata and thereby the included fossils.

Like extant organisms, fossils vary in size from microscopic, such as single bacterial cells only one micrometer in diameter, to gigantic, such as dinosaurs and trees many meters long and weighing many tons. A fossil normally preserves only a portion of the deceased organism, usually that portion that was partially mineralized during life, such as the bones and teeth of vertebrates, or the chitinous exoskeletons of invertebrates. Preservation of soft tissues is rare in the fossil record. Fossils may also consist of the marks left behind by the organism while it was alive, such as the footprint or feces (coprolites) of a reptile. These types of fossil are called trace fossils (or ichnofossils), as opposed to body fossils. Finally, past life leaves some markers that cannot be seen but can be detected in the form of biochemical signals; these are known as chemofossils or biomarkers.

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