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Permineralization is a process of fossilization of bones and tissues in which mineral deposits form internal casts of organisms. Carried by water, these minerals fill the spaces within organic tissue. Because of the nature of the casts, permineralization is particularly useful in studies of the internal structures of organisms, usually of plants.
A fossil (from Classical Latin fossilis, lit. 'obtained by digging') [ 1] is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants.
Further, the fossil gets narrower as it attaches to a rhizoid, a place where one would expect there to be the highest concentration of vascular tissue (as this is where the peak transport occurs). However, because the fossil is a cast, the narrowing in fact represents a constriction of the cavity, into which vascular tubes encroach as they widen.
Cast of Isotelus rex, the largest-known trilobite, from the middle to upper Ordovician of North America Cheirurus sp., middle Ordovician age, Volkhov River, Russia The Early Ordovician is marked by vigorous radiations of articulate brachiopods, bryozoans, bivalves, echinoderms, and graptolites, with many groups appearing in the fossil record ...
Petrifaction. In geology, petrifaction or petrification (from Ancient Greek πέτρα (pétra) 'rock, stone') is the process by which organic material becomes a fossil through the replacement of the original material and the filling of the original pore spaces with minerals. Petrified wood typifies this process, but all organisms, from ...
Biostratigraphy is the branch of stratigraphy which focuses on correlating and assigning relative ages of rock strata by using the fossil assemblages contained within them. [ 1] The primary objective of biostratigraphy is correlation, demonstrating that a particular horizon in one geological section represents the same period of time as another ...
Homo habilis ( lit. 'handy man') is an extinct species of archaic human from the Early Pleistocene of East and South Africa about 2.3 million years ago to 1.65 million years ago ( mya ). Upon species description in 1964, H. habilis was highly contested, with many researchers recommending it be synonymised with Australopithecus africanus, the ...
Endocast. An endocast is the internal cast of a hollow object, often referring to the cranial vault in the study of brain development in humans and other organisms. [1] Endocasts can be artificially made for examining the properties of a hollow, inaccessible space, or they may occur naturally through fossilization .