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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.
Comparing the record about the discordance in the record to the full rock column shows the non-occurrence of the missing species and that portion of the local rock record, from the early part of the middle Eocene is missing there. This is one form of discordancy and the means geologists use to compensate for local variations in the rock record.
Archaic biological features and organisms are succeeded in the fossil record by more modern versions. For instance, paleontologists investigating the evolution of birds predicted that feathers would first be seen in primitive forms on flightless predecessor organisms such as feathered dinosaurs. This is precisely what has been discovered in the ...
The fossil record is very uneven and, with few exceptions, is heavily slanted toward organisms with hard parts, leaving most groups of soft-bodied organisms with little to no fossil record. [39] The groups considered to have a good fossil record, including a number of transitional fossils between traditional groups, are the vertebrates, the ...
Hence the fossil record is very incomplete, increasingly so further back in time. Despite this, it is often adequate to illustrate the broader patterns of life's history. [58] There are also biases in the fossil record: different environments are more favorable to the preservation of different types of organism or parts of organisms. [59]
The fossil record provides examples of transitional species that demonstrate ancestral links between past and present life forms. [45] One such transitional fossil is Archaeopteryx , an ancient organism that had the distinct characteristics of a reptile (such as a long, bony tail and conical teeth ) yet also had characteristics of birds (such ...
Stromatolites are a major constituent of the fossil record of the first forms of life on Earth. [24] They peaked about 1.25 billion years ago (Ga) [22] and subsequently declined in abundance and diversity, [25] so that by the start of the Cambrian they had fallen to 20% of their peak.
In archaeology and paleontology a faunal assemblage is a group of animal fossils found together in a given stratum. [1] In a non-deformed deposition, fossils are organized by stratum following the laws of uniformitarianism [2] and superposition, [3] which state that the natural phenomena observable today (such as death, decay, or post-mortem transport) also apply to the paleontological record ...