Zhou et al., 2003 (Jehol exceptional preservation) Flashcards
Fieldwork in the … … Jehol Group in northeastern China has revealed an abundance of exceptionally well-preserved fossils, including … … dinosaurs and early …, which provide additional, indisputable support for the dinosaurian ancestry of …, and new evidence on the evolution of … and ….
Early Cretaceous, feathered theropod, birds, birds, feathers, flight
Specimens of putative … and primitive … are clarifying details of the early radiations of these major clades too.
angiosperms (proposed as the oldest flowering plants), mammals
Detailed …-… preservation of the organisms from the Jehol … is providing palaeontology insights that would not normally be accessible from the fossil record
soft-tissue, Biota
Soft tissues and associated … structures are exceptionally well-preserved in many of the theropod, bird and mammal specimens from the Jehol Biota
integumentary
The Jehol Biota includes representatives of almost all major clades of … … … and … vertebrates, a wide variety of … and a diverse ….
lower cretaceous terrestrial, aquatic, invertebrates, flora
The Jehol Biota provides a rare, incredibly detailed picture of an … Early Cretaceous terrestrial ….
intact, ecosystem
Composed of deposits of weakly … to finely bedded … sediments, mainly low-energy … and …, intercalated with extrusive … and …. The deposits are associated with freshwater … rather than rivers or deltas, which are more laterally variable, or marine environments. There was increased … and … activity during the time of the Jehol formation.
laminated, siliciclastic, sandstones, shales, basalts, tuffs (volcanic), lake, tectonic, volcanic
The regional …, in combination with the presence of numerous … …, provided ideal environments for the … … of the Jehol Biota.
volcanism, shallow lakes, exceptional preservation
Preservation of complete … shells, arthropod …, vertebrate … and terrestrial plant stems with associated structures indicates that all of these specimens originated in … … to low-energy lacustrine depositional sites and were not … over extensive …. Individual elements are generally unbroken and display little or no abrasion.
articulated, exoskeletons, skeletons, close proximity, transported, distances
Dead organisms entered the lakes, were buried … and encased in …-… sediments.
rapidly, fine-grained
Tuff layers are strongly correlated with … … events, from pyroclastic flows and ash tuff falls. These conditions sealed the organisms and promoted … conditions ideal for preserving the detail and soft tissues of specimens. Additionally, these conditions prevent … from … organisms.
mass mortality, anoxic, bioturbation, burrowing
These types of conditions are known as …-… conditions
Konzervat-Lagerstatten
… structures (filaments, feathers and fur) are known from …, …, … and …
pterosaur, dinosaur, bird, mammal
Other soft tissues commonly preserved include keratinous …, … impressions and cartilaginous elements…. contents is also common.
beaks, skin, stomach
The three-dimensionally preserved whole specimens often lack … …, suggesting they were preserved in a single, catastrophic mass mortality event
bedding planes
Jehol’s diverse theropod fauna spans the phylogenetic transition phylogenetic transition from basal … to … …
coelurosaurian, ornithurine birds
The basal coelurosaur … possesses and extensive covering of filamentous integumentary structures, considered to be the precursors of true feathers
Sinosauropteryx
The coelurosaur …, for example, bears feathers of modern appearance (central rachis supports a branching patten of barbs)
Protarchaeopteryx
All of these animals lacked … specialisations and most were …-dwelling cursorial animals, indicating that the selective pressures responsible for initiating the development of feathers were imposed before the origin of …
flight, ground, flight
- e.g. sexual display, camouflage, species recognition, thrust generation during running/jumping, providing insulation due to evolution of endothermy
… size and … differences between sympatric Jehol taxa indicate that a rapid … diversification of … taxa occurred during the early Cretaceous.
Body, locomotory, ecological, avian
… possessed an advanced flight apparatus, including and elongated, deeply … … and a “modern” bird-like appearance - indicate … capability.
Yanornis, keeled sternum, flight
… exhibits a mosaic of therian and non-therian character states
Jeholodens
Differences in body size and locomotory features indicate that … had diversified into a number of … roles by the late Early Cretaceous.
mammals, ecological
The discovery of brachycerna flies with …, … mouhparts suggests the presence of …-… angiosperms in the Jehol flora - provides support for the suggestion that … insects might have had an important role in the origin and early evolution of … plants.
long, tubular, nectar-producing, pollinating, flowering
