Fossil
hideFossils (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.
For more information about Fossil, read the full article at
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News tagged with dinosaur bones
Evidence of the 'Lost World' -- did dinosaurs survive the end Cretaceous extinctions?
Other Sciences / Archaeology & Fossils
Apr 28, 2009 |
4.5 / 5 (14) |
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The Lost World, Sir Arthur Conan Doyle's account of an isolated community of dinosaurs that survived the catastrophic extinction event 65 million years ago, has no less appeal now than it did when it was written a century ...
A case of mistaken dino-identity
Other Sciences / Archaeology & Fossils
Jan 13, 2009 |
4 / 5 (7) |
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The official State Dinosaur of Texas is up for a new name, based on Southern Methodist University research that proved the titleholder has been misidentified.
Ancient mammal tracks found at national monument
Other Sciences / Archaeology & Fossils
Jul 24, 2009 |
5 / 5 (4) |
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(AP) -- Hundreds of tiny footprints left by mammals some 190 million years ago have been found on a canyon wall in a remote part of Dinosaur National Monument, park officials said Thursday.
Search results for dinosaur bones
Muscle cell infusion shown to strengthen sphincters in animals
Dec 04, 2009 |
4.8 / 5 (4) |
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A new study shows that muscle cells grown in the lab can restore an intestine's ability to squeeze shut properly. The work, performed in dogs and rats, might ultimately help treat patients with conditions such as gastric ...
Dating the Bronze Age
Other Sciences / Archaeology & Fossils
Dec 02, 2009 |
4.3 / 5 (3) |
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ANSTO (Australian Nuclear Science and Technology Organisation) research has shown that an area of desert in north-western China was once a thriving Bronze Age manufacturing and agricultural site. The new findings ...
Study simulated car crashes involving pregnant women
Dec 02, 2009 |
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Although states are not required to report fetal deaths in accident data, between 300 and 1,000 unborn babies die in car accidents each year. This accident fatality rate is about four times the rate for victims ...
Outpatient disc treatment gives long-term back pain relief
Dec 02, 2009 |
4 / 5 (2) |
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A randomized, controlled study comparing standard conservative therapy to a minimally invasive treatment called percutaneous disc decompression for painful herniated disc revealed that while both treatments help patients ...
North Pole wolf emails locations to researchers
Dec 01, 2009 |
4.8 / 5 (4) |
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In July the scientists, one from the United States, the other from Canada, put the satellite collar on Brutus, the leader of his wolf pack, on remote Ellesmere Island, only 600 miles from the North Pole. Their ...
Gift Guide: A focus on HD video, at many prices
Electronics / Consumer & Gadgets
Dec 01, 2009 |
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It's easier than ever to shoot high-definition video. You can do it with traditional-style camcorders, of course, but also with cameras that also are designed to take still photos - from high-end "digital ...
Overweight children may develop back pain and spinal abnormalities
Dec 01, 2009 |
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Being overweight as a child could lead to early degeneration in the spine, according to a study presented today at the annual meeting of the Radiological Society of North America (RSNA).
Holiday shopping off to mildly encouraging start
Nov 30, 2009 |
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(AP) -- After shoppers gave retailers a somewhat encouraging start to the holiday shopping season, stores now turn their attention to the online promotions known as Cyber Monday and bringing back customers ...
What a grind: Bruxism at night likely a sign of stress by day
Nov 27, 2009 |
5 / 5 (1) |
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You can practically track Steve Barkley's stress by the level of activity in his temporomandibular joint, or TMJ, the hinge joint that connects the lower jaw to the temporal bone of the skull and helps one chew, talk and ...
Tough yet stiff deer antler is materials scientist's dream
Nov 27, 2009 |
3.4 / 5 (7) |
2
Prized for their impressive antlers, red deer have been caught in the hunters' sights for generations. But a deer's antlers are much more than decorative. They are lethal weapons that stags crash together when duelling. John ...
List of search results for dinosaur bones
