Phys.org - fossil ( ... sorted: popular/1d)

Home
fossil
sorted by popularity

Related topics:

dinosaurs · fossil record · bone · teeth · proceedings of the national academy of sciences

Solar plane set for new leg of cross-country US trip

The first-ever manned airplane that can fly by day or night on solar power alone was set to soar early Wednesday on the second leg of its journey across the United States.

Technology - Energy & Green Tech

May 22, 2013

5 / 5 (3)

0

Science sinks teeth into Neanderthal weaning habits

Neanderthals may have started weaning their young from seven months of age and transferred them to solid food by just over a year, a fossil tooth study said Wednesday.

Other Sciences - Archaeology & Fossils

May 22, 2013

3.8 / 5 (4)

1

Solar plane sets distance record on US tour

The first manned aircraft that can fly day and night powered only by solar energy set a new distance record Thursday when it landed after the second leg of a cross-country US tour.

Technology - Energy & Green Tech

9 hours ago

5 / 5 (3)

1

Researchers map historic sea-level change on the New Jersey coastline

(Phys.org) —Hurricane Sandy caught the public and policymakers off guard when it hit the United States' Atlantic Coast last fall. Because much of the storm's devastation was wrought by flooding in the aftermath, ...

Space & Earth - Earth Sciences

7 hours ago

4 / 5 (1)

0

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.

This text uses material from Wikipedia, licensed under CC BY-SA

Subscribe to rss feed