A new Anseriformes, Conflicto antarcticus gen. et sp. nov., represented by associated bones of a single individual, from the early Palaeocene Antarctica is described. The taxon unlike any other known member order. medium-sized (2 kg) stem anseriform. forelimb and pectoral girdle suggest that it was flying bird, hindlimb show had elongated legs. os quadratum represents unique combination features; some are similar to features ancestral quadrate for galloanserines but such as presence three...

Anseriformes is a diverse group of birds that comprises screamers, the Magpie Goose, and swans ducks geese, with relatively rich fossil record. Waterfowl live in close relation to water bodies, but show diversity locomotory habits, being typically categorized as walkers, dabblers, divers. Owing its functional significance high preservation potential, tarsometatarsus has been considered be "key" element upon which base ecomorphological inferences waterfowl. For instance, based on features...

Many studies on avian microanatomy have established a relationship between high bone compactness (i.e., considerable degree of osteosclerosis) and diving behavior. Greatest degrees been observed in the femora humeri fossil extant penguins, Hesperornis Marsh, Polarornis gregorii Chatterjee, to somewhat lesser degree, flightless Pan-Alcidae. Within Anatidae, humeral femoral among species is greater than non-diving ones, whereas their volant close relatives. In Cayaoa bruneti Tonni, an extinct...

Avian evolution led to morphological adaptive variations in feet. Diverse foot types are accompanied by a diverse muscle system, allowing birds adopt different primary lifestyles, and display various locomotor manipulative skills. We provide insights of evolutionary functional significance on the avian architecture through Anatomical Network Analysis, methodology focused connectivity patterns anatomical parts. Here, we show that: (1) parts largely conserved living already present ancestral...

We present new specimens of a teratorn (Aves, Teratornithidae) from the Chasicoan (early late Miocene) southwestern Buenos Aires Province, Argentina. The consist an incomplete left ulna without its proximal end and two fragments radius. is very similar to, but larger than, Vultur, size relative slenderness distal shaft excludes it Cathartidae diagnostic Teratornithidae. Its length to Teratornis merriami, so wingspan would have been around 4 m. Coming sediments Barrancas Member Arroyo Chasicó...

Abstract Cayaoa bruneti , from the early Miocene Gaiman Formation of Chubut, Argentina, provides earliest evidence for diving behaviour and example flight loss within Anseriformes. It is also only known duck South America. A new phylogenetic analysis using morphological characters places as part a single radiation ducks Anatinae, sister group to Erismaturinae. Partition subsets shows that humerus femur have strongest effect in generating this phylogeny, while skull result groupings closer...

Abstract Waterfowl (Aves, Anseriformes) constitute an ancient global radiation, and understanding the pattern timing of their evolution requires a well‐corroborated phylogeny including extant species fossils. Following molecular advances in avian systematics, however, morphology has often been held as misleading, yet congruence with data shown to vary considerably among different skeletal parts. Here, we explore phylogenetic signal discrete characters lacrimal/ectethmoid region waterfowl,...

Few investigators have examined in vivo bite-force of birds, likely due, at least part, to the difficulty accessing suitable force transducers. We describe a low-cost, easy-to-build, and portable transducer with goal encouraging ornithologists improve our knowledge bite forces birds. used commercial piezo-resistive sensor (Tekscan©) construct transducer, measure captive birds different beak morphologies, including following species: Greater Rhea (Rhea americana), Black-chested Buzzard-Eagle...

Abstract Foot-propelled diving comprises the primary locomotion-based feeding strategy for many birds, including families such as Phalacrocoracidae, Anhingidae, Podicipedidae, Gaviidae, and ducks within Anatidae. While morphology of specialized divers is well known, corresponding less known birds not but capable diving, coots (Rallidae, Fulica spp.). To compare osteology with other (non-diving) Rallidae, foot-propelled that are distantly related, we considered osteological characters,...

The fossil record of the Charadriiformes in South America is scarce and limited to Neogene Argentina Peru. In present contribution, we describe a nearly complete tarsometatarsus Thinocorus rumicivorus (Least Seedsnipe) from Ensenadan Age/Stage (early-middle Pleistocene) Punta Hermengo, Buenos Aires province, Argentina, which constitutes youngest for species date. We also compare material with extant Thinocoridae. stratigraphic range predates Matuyama/Brunhes boundary coincident biozone...

PREDATORY activities do not necessarily leave marks capable of being preserved in the geological record and, sometimes, interaction between organisms same paleoenvironment is 'indirectly' recognized through phylogenetic

We restudy the holotype specimen and all alleged fossil material assigned to Cayaoa bruneti Tonni from Early Miocene marine deposits of Gaiman Formation, Patagonia, Argentina. is phylogenetically placed close Erismaturinae (=”Oxyurinae”) that contains diving birds. It was considered a flightless foot-propelled duck represents earliest example flight loss in Anatidae. carried out comparative morphometric descriptive study different species anseriforms with special attention divers, evaluate...

Abstract To study morphological evolution, it is necessary to combine information from multiple intersecting research fields. Here, we report on the structure of bony and muscular elements craniomandibular complex birds, highlighting its architecture complexity (or simplification) in context anatomical networks Band‐winged Nightjar Systellura longirostris (Caprimulgiformes, Caprimulgidae). This species has skull osteology jaw myology that departs general structural plan Neornithes considered...