Pleistocene frogs from the Darling Downs,southeastern Queensland,and their palaeoenvironmental significance

Systematic collecting from fluvial late Pleistocene deposits from the Darling Downs, southeast Queensland, Australia, has led to the recovery of the first fossil frogs from the region, ail from the Myobatrachidae, a family of ground dwelling and burrowing frogs. The most common species recovered, Limnodynastes tasmaniensis, is extant on the Darling Downs. The fossil taxa include species whose extant populations inhabit arid zones(Limnodynastes sp. cf. L. spenceri), montane forests (Kyarranus spp.), and open woodlands (Neobatrachus sudelli), and indicate the existence of a mosaic of habitats during the Pleistocene. The absence of the Hylidae (tree frogs), a family common throughout the Darling Downs today, may be explained by a taphonomic bias that favours non-arboreal forms. Alternatively, hylids may have been rare or absent on the Darling Downs during the Pleistocene.     

Isotopic values of diet of Blastocerus dichotomus (marsh deer) in Paraná Basin,South America

The marsh deer (Blastocerus dichotomus, Illiger, 1815) is the largest contemporary South American deer, and its habitat includes the floodplains and wetlands of eastern South America. Throughout the Holocene these deer were widely used by indigenous societies, from the southern banks of the Amazon River to the Río de la Plata River, and from the Andean foothills to the Atlantic Ocean. However, despite the enormous ecological and archaeological importance of this ungulate in the region, our knowledge of the isotopic values of their diet is almost nonexistent. This paper is the first systematic approach to the study of the isotopic values of this mammal's diet, using archaeological and present-day samples from interconnected watersheds of the Paraná and Uruguay rivers in east-central Argentina. The results obtained from 24 measurements indicate an average value of ?21.09 ± 1.46‰ in δ¹³C collagen, with a low coefficient of variation (6.92%). The data indicate a marked preference for consumption of plants with a C₃ photosynthetic pathway. Most of the observed variability in the isotopic values corresponds to the period 900–1430 ¹⁴C years BP, a time range during which the values show higher consumption of C₄ plants. This it could be related with a period where temperature and associated humidity increased, synchronous in the area with the Medieval Climate Anomaly.