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A different forelimb posture than other Cretaceous eucosmodonts was observed in a cretaceous eucosmodont multituberculate mammal skeleton with a well- conserved shoulder girdle found in Mongolia. Locomotion change seen in the skeletal structure had occurred in multituberculates and therians in the mid Jurassic period. Other postural and mobility characteristics of the specimen are similar to that of therians.

The Ukhaa Tolgod region, Gobi Desert, Mongolia, contains a large number of vertebrate fossils from the Upper Cretaceous period. There are about 100 dinosaur articulated skeleton fossils and many nests containing the initial discovery of theropod dinosaur embryos. Skulls of almost 400 mammals and lizards and skeletons of Mononykus, a bird, have been found. Most of the mammals are multituberculates. A large number of different small vertebrates are also seen. The rapid burial of animals after sudden death in arid conditions probably after sandstorms are the reason for the excellent preservation and abundance of fossils.

An analysis of geomagnetic data obtained from Cretaceous submarine basaltic glass experiments reveals that the beginning and end of the Cretaceous normal superchron (CNS) period contain dipole lows. This extension theorizes that palaeointensities and reversal frequency control processes are independent of each other. The CNS period exihibits long periods of normal geomagnetic field polarity.

The discovery two specimens of a flightless bird from the Upper Cretaceous of Mongolia is reported. The flightless bird was classified under a new genus and species, Mononychus olecranus. It is an avialian theropod dinosaur with a short, robust forelimb bearing a single stout claw. A carinate sternum, reduced fibula and other features mark it as a closer relative of modern birds than Archeopteryx lithographica.

Vorona berivotrenesis is the first specimen of a primitive bird from the Cretaceous period of Madagascar and the first avian skeletal remains from the Mesozoic era from Gondwana. V. berivotrenesis has features common to the non-avian maniraptorans and basal birds. It has derived structures in the femural head, fibula, tarsometatarsus and proximal tarsals which are present in avian birds. Due to these mixed features, it has been placed with a clade of Patagopteryx and Ornithurae and in a trichotomy with Enantiornithes. The V. berivotrenesis lacks any phylogenetic relationship with the Neornithes.

The partial tyrannosaur skeleton found in 1993 in the Early Cretaceous region of the Sao Khua Formation, northeastern Thailand, contains both features primitive to and similar to those seen in Late Cretaceous tyrannosaurids. The tyrannosaur has been named Siamotyrannus isanensis. The skeleton consists of the left pelvis, sacrum, 13 anteriormost caudal and five dorsal vertebrae. The discovery of an Early Cretaceous tyrannosaur in Thailand indicates these dinosaurs evolved in Asia and later spread to North America probably in the early Late Cretaceous era.

The existence of different families of monotremes during the Early Cretaceous period in the Gondwana region of Australia indicates a history of evolution and diversification significantly earlier than the Cretaceous with one dispersal of ornithorhynchids, by early Paleocene, to the South American sector. A study of the Mesozoic mammal, Kollikodon ritchiei shows that kollikodontids may be close associates of tachyglossids, ornithorhynchids and steropodontids. The dental morphology of these monotremes are discussed.

The evolution of birds from theropod dinosaurs may well have been clarified by the identification of a fossil skull from the Late Cretaceous of Mongolia that merges the features of the two groups. The specimen, unearthed in 1965 by the Polish-Mongolian Paleontological Expedition, has been given the scientific name Archaeornithoides deinosauriscus. The skull's maxillary palatal shelf and teeth reveal that this theropod had bird-like anatomical characteristics.

Modern palaeontologist face difficulties while identifying the species having no relation with modern species. Case of three small teeth fossils of mammals from the early cretaceous of Morocco and problems in interpretation is presented. Problems faced by the palaeontologists in identifying phosphatic, tooth-like microfossils are also presented.

Synsacrum fragments of a large bird were discovered in the continental Upper Cretaceous of South-Eastern France. Fossil eggs found in the Upper Cretaceous of Provence and presumed to be Dinosaur eggs could be bird eggs as suggested by this discovery. Anatomical details considered for classifying this fragment to be that of a bird are discussed.

The discovery of fossil birds from the 75-million-year-old Upper Cretaceous of Mongolia is reported. The specimens were designated as Mononychus and are important because they provide an unambiguous character set that could be the basis for changes in the understanding of primitive birds. One of the most striking features of the specimens was a forelimb which is short, powerfully built and bears single digit with a robust claw, indicating a flightless bird.