Abstract Ecomorphological and biogeochemical (trace element, carbon, nitrogen, oxygen isotope ratios) analyses have been used for determining the dietary niches habitat preferences of large mammals from lower Pleistocene deposits at Venta Micena (Guadix-Baza Basin, Spain). The combination these two approaches takes advantage strengths overcome weakness both approaches. range δ13Ccollagen values ungulate species indicates that C3 plants were dominant in diet mammals. vary among ungulates:...

Body size is a crucial life history parameter for an organism. Therefore, mass estimation fossil species important many kinds of analyses. Several attempts have been made to yield equations applicable dinosaurs. In this paper, we offer bi- and multivariate based on log transformed appendicular skeleton data from sample 16 theropods which were known reasonably complete skeletal remains, spanning wide range. masses the included taxa had found by displacement methods scale models, measurements...

Sloths, like other xenarthrans, are an extremely interesting group of mammals that, after a long history evolution and diversification in South America, became established on islands the Caribbean later reached North America during Great American Biotic Interchange. In all three regions, they were part impressive Pleistocene megafauna. Most taxa extinct only two small, distantly related tree-dwelling genera survived. Here, we incorporate several recently described sloths into assembled...

The end of the Pleistocene was marked by extinction almost all large land mammals worldwide except in Africa. Although debate on extinctions has focused roles climate change and humans, impact perturbations depends properties ecological communities, such as species composition organization interactions. Here, we combined palaeoecological data, food-web models community stability analysis to investigate if differences between modern mammalian assemblages help us understand why megafauna died...

Abstract Body masses of some South American dinosaurs are estimated. The sauropod Argentinosaurus huinculensis reached 73 tonnes, and therefore, is the largest all land animals whose mass has been rigorously obtained. Another sauropod, Antarctosaurus giganteus, was second largest, at nearly 69 while wichmannianus 34 tonnes. A third bizarre-looking Amargasaurus cazaui, much smaller, with a body only 2.5 Among theropods, strangely looking, horned Carnotaurus sastrei, volumetrically estimated...

Human-megafauna interaction in the Americas has great scientific and ethical interest because of its implications on Pleistocene extinction. The Arroyo del Vizcaíno site near Sauce, Uruguay already yielded over 1000 bones belonging to at least 27 individuals, mostly giant sloth Lestodon. assemblage shows some taphonomic features suggestive human presence, such as a mortality profile dominated by prime adults little evidence major fluvial transport. In addition, several present deep,...

For over 200 years, fossils of bizarre extinct creatures have been described from the Americas that ranged giant ground sloths to 'native' South American ungulates, groups mammals evolved in relative isolation on America. Ground belong xenarthrans, a group with modern although morphologically and ecologically very different representatives (anteaters, armadillos sloths), which has proposed be one four main eutherian clades. Recently, proteomics analyses bone collagen recently used yield...

Our objective is to construct well-calibrated prediction sets for a time-to-event outcome subject right-censoring with guaranteed coverage. approach inspired by modern conformal inference literature, in that, unlike classical frameworks, we obviate the need well-specified parametric or semi-parametric survival model accomplish our goal. In contrast existing methods data, which restrict censoring be of Type I, whereby potential times are assumed fully observed on all units both training and...

Species distribution models (SDMs) for the last interglacial (LIG), global glacial maximum (LGM) and Holocene climatic optimum (HCO) were generated three extinct South American Pleistocene mylodontid giant sloths, Glossotherium robustum , Lestodon armatus Mylodon darwinii . They are recorded co-occurring in some localities including Arroyo del Vizcaíno site (AdV) Uruguay. Co-occurrence records studied based on overlap of their areas potential distributions, compared with available biome...

Finite element analyses (FEA) were applied to assess the lower jaw biomechanics of cingulate xenarthrans: 14 species armadillos as well one Pleistocene pampathere (11 extant taxa and extinct forms Vassallia, Eutatus Macroeuphractus). The principal goal this work is comparatively biomechanical capabilities mandible based on FEA relate obtained stress patterns with diet preferences variability, in through an ecomorphology approach. results showed that omnivorous have stronger mandibles than...

Nutrient foramina are small openings in the periosteal surface of mid-shaft region long bones that traverse cortical layer and reach medullary cavity. They important for delivery nutrients oxygen to bone tissue crucial repair remodeling over time. The nutrient femur's diaphysis related energetic needs femur have been shown be maximum metabolic rate (MMR) taxa. Here, we investigate relationship between foramen size body mass as a proxy aerobic capacity taxa living extinct xenarthrans,...

The traditional point of view that fossil ground sloths (Xenarthra) were a relatively uniform, ecologically little diverse group has been recently challenged. Marine habits have ascribed to Thalassocnus natans the Pliocene Peru. Also, more diet proposed by one us (R.A.F.) for some Lujanian (late Pleistocene-early Holocene South America genera sloths. In this paper, an aspect latter hypothesis is tested, i.e. Megatherium americanum had morphological features are better explained its having...

Biogeochemical techniques have become most useful in the determination of dietary niches fossil mammalian species and reconstruction past communities. Stable isotopes analyses ( 13 C 15 N) were applied to study diet mylodontids Lestodon Glossotherium other Late Pleistocene megamammals. Only samples for these ground sloths yielded reliable values. The results δ N L. armatus G. robustum could be related a non-ruminant herbivorous physiology or climate inferred Pampean region Pleistocene,...

Fariña, R.A. 1995 11 30 Limb bone strength and habits in large glyptodonts. The masses of some Pleistocene species the fossil family Glyptodontidae (Mammalia; Xenarthra) were estimated from volumes models. Their centres mass also estimated. Dimensions limb bones muscles used to assess athleticism these species, using an approach previously applied dinosaurs. femora show higher athletic indicators (even when supporting whole weight animal) than humeri quadrupedal stance. It is therefore...

Ecomorphological and biogeochemical (trace element, carbon, nitrogen, oxygen isotope ratios) analyses have been used for determining the dietary niches habitat preferences of large mammals from lower Pleistocene deposits at Venta Micena (Guadix-Baza Basin, Spain). The combination these two approaches takes advantage strengths overcome weakness both approaches. range δ 13 C collagen values ungulate species indicates that 3 plants were dominant in diet mammals. vary among ungulates:...