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Once, paleontologists would have been limited by its colorless fossil remains, but now they know what the snake ...
Fossils found in Morocco from the long-extinct group of sea creatures called trilobites, including rarely seen soft-body parts, may be previously unseen animals that left distinctive fossil ...
The minimal superficial changes to living fossils are mistakenly declared the absence of evolution, but they are examples of stabilizing selection, which is an evolutionary process -- and perhaps the dominant process of morphological evolution.
Lineages that exhibit stasis over very short time scales are not considered living fossils; what is poorly-defined is the time scale over which the morphology must persist for that lineage to be recognized as a living fossil.
In short, not even the most dramatic examples of living fossils can be expected to be without changes, no matter how persistently constant their fossils and their extant specimens might seem.
All of these were described from fossils before later found alive (2 species, 10 species, one species, and one species respectively).
The average species turnover time, meaning the time between when a species first is established and when it finally disappears, varies widely among phyla, but averages about 2–3 million years.
So a living taxon that had long been thought to be extinct could be called a Lazarus taxon once it was discovered to be still extant.
As a rule, to be considered a living fossil, the fossil species must be old relative to the time of origin of the extant clade.
The totality of fossils 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.
The term "living fossil" is much misunderstood in popular media in particular, in which it often is used meaninglessly.
In professional literature the expression seldom appears and must be used with far more caution and it has been used inconsistently.