Search results
Results from the WOW.Com Content Network
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.
Jefferson presented fossil bones of a ground sloth found in a cave in western Virginia and named the genus . The species was ultimately named Megalonyx jeffersonii in his honor. [ 4 ] [ 5 ] [ 6 ] Jefferson corresponded with Cuvier, including sending him a shipment of highly desirable bones of the American mastodon and the woolly mammoth .
Fossil wood is wood that is preserved in the fossil record. Wood is usually the part of a plant that is best preserved (and most easily found). Fossil wood may or may not be petrified. The fossil wood may be the only part of the plant that has been preserved; [101] therefore such wood may get a special kind of botanical name.
Paleoanthropology or paleo-anthropology is a branch of paleontology and anthropology which seeks to understand the early development of anatomically modern humans, a process known as hominization, through the reconstruction of evolutionary kinship lines within the family Hominidae, working from biological evidence (such as petrified skeletal remains, bone fragments, footprints) and cultural ...
Living or freshly dead bones are somewhat resilient, so metal blade injuries to bone generate a linear cut with relatively clean edges rather than irregular shattering. [13] Archaeologists have attempted to use the microscopic parallel scratch marks on cut bones in order to estimate the trajectory of the blade that caused the injury.
This is because hard organic parts, such as bones, teeth, and shells resist decay, and are the most commonly preserved and found animal fossils. Exclusively soft-bodied animals —such as jellyfish , flatworms , nematodes , and insects —are consequently rarely fossilized , as these groups do not produce hard organic parts.
The fossil has been identified as a new silesaurid, an extinct group of reptiles. Paleontologists debate whether silesaurids were true dinosaurs or possibly a precursor to the creatures that once ...
There are two principal types of bones: Dermal bone is directly formed in the dermis (skin), usually growing from initially thin plates. Among others, most bones forming the outer surface of the skull and lower jaws are dermal bones. In contrast, endochondral bone is formed from a cartilaginous precursor, which ossifies (turn into bone). [1 ...