This is supported by fossils of the freshwater Odontochelys semitestacea or " half-shelled turtle with teeth ", from the late Triassic, which have been found near Guangling in southwest China.

Early fossil tetrapods have been found in marine sediments, and because fossils of primitive tetrapods in general are found scattered all around the world, they must have spread by following the coastal lines — they could not have lived in freshwater only.

Their fossils occur in ancient beds deposited in both freshwater and marine environments.

This is supported by their fossils usually found in deposits indicative of fully marine environments, lacking any freshwater influx.

The fossils at Riversleigh are rare because they are found in soft freshwater limestone which hasn't been compressed.

The area also includes Purse State Park, well known for its fossil shark teeth, Turritella snails, and other fossils of Paleocene geological age, and other protected wild areas along the Potomac River's freshwater tidal ( estuarine ) shore.

In freshwater deposits, generally poor in fossils, the well-preserved clam shrimp shells are found quite often.

Based on the number of fossils discovered, the aquatic Sarcosuchus was probably plentiful in these warm, shallow, freshwater habitats.

It has a diverse assemblage of unusually well-preserved marine, euryhaline, freshwater, flying, and terrestrial fossils ( invertebrates, vertebrates, and plants ).

This facies contains a well-preserved mixed assemblage of terrestrial ( conifers, insects, myriapods, reptiles ), freshwater ( ostracods ), aquatic ( amphibians, reptile ), brackish or euryhaline ( ostracods, eurypterids, microconchids, fish ), and marine ( brachiopods, echinoderms ) fossils.

A private estate in Denton houses a series of large ponds, and a freshwater spring, St. Christopher's Well, hidden in a grotto built from fossils and shells.

Other fossils found with the Einiosaurus material include freshwater bivalves and gastropods, which imply that these bones were deposited in a shallow lake environment.

Near Yuxi city is Fuxian Lake, the second-deepest freshwater lake in China, where there have been discovered ancient fossils that are now in the possession of the Yuxi museum.

Karl Mayer-Eymar ( 1826 – 1907 ) a Swiss geologist and palaeontologist, studied fossils between gypsum-bearing, brackish and freshwater sediment layers and identified them as having been deposited just before the end of the Miocene Epoch.

Hyphalosaurus fossils are relatively widespread in the Jehol beds, which represent a series of freshwater lakes.

Palaeontologist Christopher McGowan examined a copy she made of an 1824 paper by William Conybeare on marine reptile fossils and noted that the copy included several pages of her detailed technical illustrations that he was hard pressed to tell apart from the original.

The American fossils were initially believed to be some sort of reptile, hence the suffix -" saurus ", but later found to be a marine mammal.

With some reservation, Harlan speculated that the fossils belonged to a ( 50 m ft long ) marine reptile, for which he suggested the name Basilosaurus, meaning “ King reptile ”.

He is probably best known for his ground-breaking work on marine reptile fossils in the 1820s, including important papers for the Geological Society of London on ichthyosaur anatomy and the first published scientific description of a plesiosaur.

The name " phytosaur " means " plant reptile ," as the first fossils of phytosaurs were mistakenly thought to belong to plant eaters.

The area around Big Water had been subject to several expeditions by teams from the Museum of Northern Arizona ( MNA ), and was known for its abundance of marine reptile fossils, especially plesiosaurs.

Nothosaurus ( meaning false reptile ) is an extinct genus of sauropterygian reptile from the Triassic period, approximately 240-210 million years ago, with fossils being distributed from North Africa and Europe to China.

Subsequent investigations by Dawson led to the discovery of one of the most important fossils in the history of science, Hylonomus lyelli, which remains the earliest known sauropsid ( reptile ) in the history of life, but not oldest known amniote, the group that includes all vertebrates that can reproduce out of water.

They underwent ecdysis in a similar manner to extant chelicerates, and most fossils are thought to be of exuviae, rather than cadavers.

Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour ( in this case, diet ) rather than morphology.

The ichthyosaurs, plesiosaurs, and pterosaur she found, along with the first dinosaur fossils which were discovered by Gideon Mantell and William Buckland during the same period, showed that during previous eras the earth was inhabited by creatures very different from those living today, and provided important support for another controversial suggestion of Cuvier's: that there had been an " age of reptiles " when reptiles rather than mammals had been the dominant form of animal life.

For example, the age of fossils is based on radiocarbon dating which is justified by reasoning that radioactive decay follows a Poisson process rather than a Bernoulli process.

Gold modified his hypothesis and presented it in a 1992 paper " The Deep Hot Biosphere " in the Proceedings of the National Academy of Sciences, Gold suggested that coal and crude oil deposits have their origins in natural gas flows which feed bacteria living at extreme depths under the surface of the Earth ; in other words, oil and coal are produced through tectonic forces, rather than from the decomposition of fossils.

Franz Boas removed the idea of unilineal cultural evolution from the realm of serious anthropological research as too simplistic, allowing tribes to be studied in their own right, rather than stepping stones to civilization or " living fossils ".

They are, however, quite distinctly united by their anatomy, and the family's phylogeny as well as the most ancient fossils of this order suggest that the original lampriform was indeed rather " opah-shaped ".

A number of Devonian fossils termed fucoids, from their resemblance in outline to species in the genus Fucus, have proven to be inorganic rather than true fossils.

Based on this and co-occurring fossils, one plausible hypothesis for the origin of polyplacophora has that they formed when an aberrant monoplacophoran was born with multiple centres of calcification, rather than the usual one.

In a series of lectures and papers that made detailed comparisons between living mammals and fossil remains Cuvier was able to establish that the fossils were remains of species that had become extinct — rather than being remains of species still alive elsewhere in the world, as had been widely believed.

Although not well known from fossils, the evolution of piculets is now considered rather straightforward.

The presence of fossils typical of the shorter-winged and more delicate G. c. cerceris in the same deposits suggests that brodkorbi was not ancestral to the " Florida Gallinule " of our time but rather to the more northernly " Common Gallinule ".

The presence of fossils typical of the shorter-winged and more delicate G. c. cerceris in the same deposits suggests that brodkorbi was not ancestral to the " Florida Gallinule " of our time but rather to the more northernly " Common Gallinule ".

Unusual fusions in cranial elements or asymmetries in the same are probably evidence that one is examining the fossils of an extremely old individual rather than a diseased one.

But, in general, transitional fossils are considered to have features that illustrate the transitional anatomical features of actual common ancestors of different taxa, rather than to be actual ancestors.

The two living species thus seem to be representatives of an entirely extinct and ( as Passerida go ) rather ancient lineage, as certainly as this can be said in the absence of actual fossils.

Trace fossils provide us with indirect evidence of life in the past, such as the footprints, tracks, burrows, borings, and feces left behind by animals, rather than the preserved remains of the body of the actual animal itself.

However, most trace fossils are rather less conspicuous, such as the trails made by segmented worms or nematodes.

The manuscript does not take the form of a single linear script, but is rather a mixture of Leonardo's observations and theories on astronomy ; the properties of water, rocks, and fossils ; air, and celestial light.

Since fossils of rather modern-looking Cnidarians have been found in the Doushantuo lagerstätte, the Cnidarian and bilaterian lineages would have diverged well over.

Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour ( in this case, diet ) rather than morphology.