According to the fossil record, Lissamphibia, which includes all modern amphibians and is the only surviving lineage, may have branched off from the extinct groups Temnospondyli and Lepospondyli at some period between the Late Carboniferous and the Early Triassic.

There are large gaps in the fossil record but the discovery of a proto-frog from the Early Permian in Texas in 2008 provided a missing link with many of the characteristics of modern frogs.

They are present in the lower Cambrian fossil record along with trilobites from the Redlichiida, Corynexochida, and Ptychopariida orders.

In contrast, their wide geographic dispersion in the fossil record is uncharacteristic of benthic animals, suggesting a pelagic existence.

However, as the preservation of behaviour in the fossil record is exceedingly rare, these ideas cannot readily be tested.

The fossil record of branchiopods extends back at least into the Upper Cambrian and possibly further.

The fossil record indicates that birds emerged within theropod dinosaurs during the Jurassic period, around 160 million years ( Ma ) ago.

Mineralized skeletons of bryozoans first appear in rocks from latest Cambrian period, about, making it the last major phylum to appear in the fossil record.

( The pre-Cambrian fossil record of animals is sparse and ambiguous.

Furthermore, great apes are not found in the fossil record in the Americas, and no Bigfoot remains have ever been found.

Paleobotanists study ancient plants in the fossil record.

Because the fossil record of chordates is poor, only molecular phylogenetics offers a reasonable prospect of dating their emergence.

Some fern orders such as Gleicheniales appeared as early in the fossil record as the Cretaceous, and achieved an early broad distribution.

The K – T boundary represents one of the most dramatic turnovers in the fossil record for various calcareous nanoplankton that formed the calcium deposits that gave the Cretaceous its name.

The turnover in this group is clearly marked at the species level .< ref > Statistical analysis of marine losses at this time suggests that the decrease in diversity was caused more by a sharp increase in extinctions than by a decrease in speciation .< ref > The K – T boundary record of dinoflagellates is not as well-understood, mainly because only microbial cysts provide a fossil record, and not all dinoflagellate species have cyst-forming stages, thereby likely causing diversity to be underestimated.

Radiolaria have left a geological record since at least the Ordovician times, and their mineral fossil skeletons can be tracked across the K – T boundary.

There is variability in the fossil record as to the extinction rate of marine invertebrates across the K – T boundary.

However, the fossil record for frog families and genera is uneven.

The dinosaur fossil record has been interpreted to show both a decline in diversity and no decline in diversity during the last few million years of the Cretaceous, and it may be that the quality of the dinosaur fossil record is simply not good enough to permit researchers to distinguish between the options.

Whether the extinction occurred gradually or very suddenly is debatable, as both views have support in the fossil record.

For example, periods of high oxygen concentrations determined from ice core samples have been associated with fauna of a larger scale in the fossil record, while periods of low oxygen concentrations have been associated with fauna of a smaller scale in the fossil record.

The fossil record of slipper lobsters extends back 100 – 120 million years, which is considerably less than that of slipper lobsters ' closest relatives, the spiny lobsters.

The fossil record of clawed lobsters extends back at least to the Valanginian Age of the Cretaceous.

One significant earlier fossil is Cancrinos claviger, which was described from Upper Jurassic sediments at least, and may represent either an ancestor of modern slipper lobsters, or the sister group to the family Scyllaridae sensu stricto.

Nephrops is a genus of lobsters comprising a single extant species, Nephrops norvegicus ( the Norway lobster or Dublin Bay prawn ), and several fossil species.

It comprises five extant superfamilies, two of crayfish ( Astacoidea and Parastacoidea ), one of true lobsters ( Nephropoidea ), one of reef lobsters ( the genus Enoplometopus ), and a number of fossil taxa.

The Glypheoidea ( containing the glypheoid lobsters ), is a group of lobster-like decapod crustaceans which forms an important part of fossil faunas, such as the Solnhofen limestone.

Although there is no fossil record of reef lobsters, there is some evidence that they may be related to the extinct genus Eryma which lived from the Permo-Triassic to the late Cretaceous.

True lobsters, or clawed lobsters are crustaceans of the family Nephropidae, as well as their fossil relatives.

Succinite has a hardness between 2 and 3, which is rather greater than that of many other fossil resins.

The country has not discovered sources of fossil fuels — apart from minor coal deposits — but its mountainous terrain and abundant rainfall have permitted the construction of a dozen hydroelectric power plants, making it self-sufficient in all energy needs, except oil for transportation.

Of the three fossil fuels, coal has the most widely distributed reserves ; coal is mined in over 100 countries, and on all continents except Antarctica.

The development of commuter rail services has become popular today, with the increased public awareness of congestion, dependence on fossil fuels, and other environmental issues, as well as the rising costs of owning, operating and parking automobiles.

In recent years, the diversity of fossil hydrochoerines has been substantially reduced.

The main sources of knowledge about the evolutionary process has traditionally been the fossil record, but since the development of genetics beginning in the 1970s DNA analyses has come to occupy a place of comparable importance.

The fossil wood may be the only part of the plant that has been preserved, with the rest of the plant completely unknown: therefore such wood may get a special kind of botanical name.

Since Darwin's time, the fossil record has been pushed back to between 2. 3 and 3. 5 billion years before the present.

Much focus has been put on the illegal fossil dealing in China, where many specimens have been stolen.

Dyson agrees that anthropogenic global warming exists, and has written that " ne of the main causes of warming is the increase of carbon dioxide in the atmosphere resulting from our burning of fossil fuels such as oil and coal and natural gas.

An unidentifable finch fossil from the Messinian age, around 12 to 7. 3 million years ago ( Ma ) during the Late Miocene subepoch, has been found at Polgárdi in Hungary.

The brown hyena has sometimes been placed in a separate genus Parahyaena, or even included in the otherwise fossil genus Pachycrocuta, but recent sources have tended to place it in Hyaena.

As the fossil record for the Cryptobranchidae shows an Asian origin for the family, the story of how these salamanders made it to the eastern U. S. has been a point of scientific interest.

Although learning about the construction of ancient eyes through fossil evidence is problematic due to the soft tissues leaving no imprint or remains, genetic and comparative anatomical evidence has increasingly supported the idea of a common ancestry for all eyes.

Analysis of jaguar mitochondrial DNA has dated the species ' lineage to between 280, 000 and 510, 000 years ago, later than suggested by fossil records.

In his view, nuclear energy is the only realistic alternative to fossil fuels that has the capacity to both fulfill the large scale energy needs of humankind while also reducing greenhouse emissions.

Several fossil birds have been erroneously ascribed to the kingfishers, including Halcyornis, from the Lower Eocene rocks in Kent, which has also been considered a gull, but is now thought to have been a member of an extinct family.

The camelid lineage has a good fossil record.

As knowledge has increased, paleontology has developed specialized sub-divisions, some of which focus on different types of fossil organisms while others study ecology and environmental history, such as ancient climates.

It has been demonstrated that changes in biodiversity through the Phanerozoic correlate much better with the hyperbolic model ( widely used in demography and macrosociology ) than with exponential and logistic models ( traditionally used in population biology and extensively applied to fossil biodiversity as well ).

One fossil subspecies has been identified.