Approximately 60 % of late-Cretaceous Scleractinia coral genera failed to cross the K – T boundary into the Paleocene.

However, the use of data from coral fossils to support K – Pg extinction and subsequent Paleocene recovery must be weighed against the changes that occurred in coral ecosystems through the K – T boundary.

Most species of brachiopods, a small phylum of marine invertebrates, survived the K – Pg extinction event and diversified during the early Paleocene.

According to fossil evidence, the primitive ancestors of primates may have existed in the late Cretaceous period around 65 million years ago ; the oldest known primate is the Late Paleocene Plesiadapis, circa 55 – 58 million years ago .< ref name = ChatterjeeEtal2009 >

The global climate during the Paleogene departed from the hot and humid conditions of the late Mesozoic era and began a cooling and drying trend which, although having been periodically disrupted by warm periods such as the Paleocene – Eocene Thermal Maximum, persists today.

It is now thought that the first passerines evolved in Gondwana at some time in the Paleogene, maybe around the Late Paleocene some 60 – 55 mya.

Although no mass extinctions of marine diatoms have been observed during the Cenozoic, times of relatively rapid evolutionary turnover in marine diatom assemblages occurred near the Paleocene – Eocene boundary and at the Eocene – Oligocene boundary.

An extinct Australian Pliocene species of Liasis, the Bluff Downs giant python, reached 10 m, while the Paleocene Titanoboa of South America reached lengths of 12 – 15 m and an estimated weight of about 1135 kilograms ( 2500 lb ).

The oldest known chameleon is Anqingosaurus brevicephalus from the Middle Paleocene ( about 58. 7 – 61. 7 mya ) of China.

** Age: Campanian ( Upper Cretaceous – Lower Paleocene )

* Sloan ( 1981 ), " Systematics of Paleocene multituberculates from the San Juan Basin, New Mexico ," pp. 127 – 160, in Lucas et al.

These include Gondwanatherium from the Campanian and Maastrichtian of Argentina ; Sudamerica from the Paleocene (~ 66 – 56 mya ) of Argentina ; Lavanify ; at least one species from the Maastrichtian of India ; an unnamed species related to Sudamerica from the Eocene of Antarctica ; and an unnamed possible gondwanathere, TNM 02067, from the Cretaceous of Tanzania.

This event, the Paleocene – Eocene Thermal Maximum ( PETM, alternatively ( ETM1 ), and formerly known as the " Initial Eocene " or "", ( IETM / LPTM )), was associated with rapid ( in geological terms ) global warming, profound changes in ecosystems, and major perturbations in the carbon cycle.

The depression has a topographic rim 25 – 30 m high, while the centre displays a slight circular rise about 1 km in diameter and 5 m high exposing strongly deformed and steeply dipping bedrock interpreted as a central uplift .< sup >,</ sup > Sedimentary rocks comprising the rim are of Early Cretaceous to Palaeogene age, while uplifted rocks in the centre are likely of Early Permian age, all part of the Canning Basin ; the impact event itself is inferred to be of Paleocene ( early Paleogene ) age or later .< sup >,</ sup >

From the beginning of this period, the temperature of the planet rose in one of the quickest ( in geological terms ) and most extreme episodes of global warming in the geological record, termed Paleocene – Eocene Thermal Maximum.

* Paleocene – Eocene Thermal Maximum ( PETM )-a sudden warming event that fundamentally altered geological and biological aspects of the planet.

# REDIRECT Paleocene – Eocene Thermal Maximum

The period was very close to the Paleocene – Eocene Thermal Maximum and the climate and ecology of the site were very different.

* Paleocene – Eocene Thermal Maximum

A lowering of sea levels and general drying during a brief arid period known as the Paleocene – Eocene Thermal Maximum drew out silica from surrounding rocks into the water immersing the flint pebbles.

the hills area of " les garrigues " ( at south of the village ) is composed of soil dating from the Cretaceous – Paleocene ( calcareous sandstone, calcareous lacustrine clay, colorful, white and ocher sands and some ferruginous ) and from the Miocene ( molasses limestone, sand and marl ).

The Amblypoda were confined to the Paleocene and Eocene periods and occurred in North America, Asia ( especially Mongolia ) and Europe.

The Cayman Rise extends from southeastern Cuba along the northern margin of the Cayman Trough toward Costa Rica and resulted from Paleocene to Eocene island arc formation with associated volcanism along an extinct subduction zone.

The Cenozoic is divided into three periods: The Paleogene, Neogene, and Quaternary ; and seven epochs: The Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene.

The oldest known primate-like mammal species, the Plesiadapis, came from North America, but they were widespread in Eurasia and Africa during the tropical conditions of the Paleocene and Eocene.

This period consists of the Paleocene, Eocene, and Oligocene Epochs.

These two groups first appeared during the late Paleocene and early Eocene ( about 54 million years ago ), rapidly spreading to a wide variety of species on numerous continents, and have developed in parallel since that time.

Chert concretions in chalk, Middle Lefkara Formation ( upper Paleocene to middle Eocene ), Cyprus.

Until recently, it was generally agreed that Eurymylus, which lived in eastern Asia and dates back to the late Paleocene or early Eocene, was an ancestor of the lagomorphs.

In the process, the core of the Alps, with the terranes that were subducted in the Paleocene and Eocene, still moves upward.

It is considered that the two families evolved around 55 millions years ago during the Early Paleogene possibly near the boundary between Paleocene and Eocene.

Parectypodus (" beside Ectypodus ") is a genus of extinct mammal that lived from the Paleocene to the Eocene of North America.

It lived during the Upper Paleocene and the Lower Eocene in North America.

They were found in the Princeton Quarry, and the deposits were dated from the Upper Paleocene to the Lower Eocene.

Systematic revision of the genus Prochetodon ( Ptilodontidae, Multituberculata ) from the late Paleocene and early Eocene of western North America.

Representatives are known from strata dating from the Upper Cretaceous through the Lower Eocene of North America, as well as the Paleocene to Eocene of Europe.

:" The occurrence on Seymour Island of sudamericids, that had become extinct in South America in the Paleocene, also indicates that isolation may have allowed extended survival of this Gondwanan group in the Eocene of Antarctica and the factors that caused their extinction did not affect this continent.

** Genus Chascacocolius ( Late Paleocene ?- Early Eocene )-basal?

Deformed Paleocene and Eocene deposits record continuing orogenic activity.

Anguids are particularly diverse during the Paleocene and Eocene in North America ; some species, such as Glyptosaurus, grew to large size and evolved a highly specialized crushing dentition.

The end of the Paleocene ( 55. 5 / 54. 8 Mya ) was marked by one of the most significant periods of global change during the Cenozoic, the Paleocene-Eocene Thermal Maximum, which upset oceanic and atmospheric circulation and led to the extinction of numerous deep-sea benthic foraminifera and on land, a major turnover in mammals.