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The first insects were landbound, but about 400 million years ago in the Devonian period one lineage of insects evolved flight, the first animals to do so. [1] The oldest insect fossil has been proposed to be Rhyniognatha hirsti, estimated to be 400 million years old, but the insect identity of the fossil has been contested. [3]
Fossils of organisms' bodies are usually the most informative type of evidence. The most common types are wood, bones, and shells. [57] Fossilisation is a rare event, and most fossils are destroyed by erosion or metamorphism before they can be observed. Hence the fossil record is very incomplete, increasingly so further back in time.
The fossil record for Lepidoptera is lacking in comparison to other winged species, and tending not to be as common as some other insects in the habitats that are most conducive to fossilization, such as lakes and ponds, and their juvenile stage has only the head capsule as a hard part that might be preserved.
The Fossil Book: A Record of Prehistoric Life (Garden City, New York: Doubleday and Courier Dover Publishing), from 482 to 760 pages. ISBN 0-486-29371-8. W. R. Hamilton and others (1974). A Guide to Minerals, Rocks and Fossils (London, England: Hamlyn Publishing Group Ltd.), 320 pages. W. B. Harland (1967).
For example, quartz is a fairly stable mineral in soils with pH>9, while alumina (Al 2 O 3) is stable in between pH 4.5 and 8 (mostly in clay). Trace elements that are usually stable in soils over a wider range of environmental conditions include lead (Pb) and zirconium (Zr) but are not always sufficiently present to be useful.
Paleontology or palaeontology is the study of prehistoric life forms on Earth through the examination of plant and animal fossils. [1] This includes the study of body fossils, tracks , burrows, cast-off parts, fossilised feces , palynomorphs and chemical residues. Because humans have encountered fossils for millennia, paleontology has a long ...
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Like other fossils, coprolites have had much of their original composition replaced by mineral deposits such as silicates and calcium carbonates. Paleofeces, on the other hand, retain much of their original organic composition and can be reconstituted to determine their original chemical properties, though in practice the term coprolite is also ...