Ancient DNA evidence for genetic continuity in arctic dogs

The domestic dog fulfills many functions for their human companions, such as hauling, guarding, and protection. Consequently, humans have taken dogs to nearly every corner of the globe. Recent translocations of Western dogs stemming from the Victorian era dog fancy have erased some of the ancient genetic signatures of these earlier migrations. Here we used DNA of ancient and modern dogs from the North American Arctic of Alaska and Greenland to assess their genetic continuity in time and space. We successfully sequenced 23 archaeological (ca. AD 1250–1910) and recent (ca. AD 1930–1990) surface-collected Canis bone and tooth samples and compared them to 51 modern Inuit Sled Dogs and to published sequences of modern Alaskan Malamutes (and additional Inuit Sled Dogs) to test for evidence of lineage replacement or genetic continuity through time. Ancient samples from Alaska and Greenland and modern sequences from Greenland all contained a high frequency of haplotype A31, which was previously described only in modern North American Arctic dogs. Thus, A31 was a common thread tying the entire North American Arctic together prior to European colonization and, in the Eastern Arctic, indicates genetic continuity between past and present dogs as well. However, A31 is rare in modern Alaskan dogs, consistent with post-colonization replacement by Eurasian matrilines.     

Namilamadeta snideri,a new diprotodontan (Marsupialia,Vombatoidea) from the medial Miocene of South Australia

Namilamadeta snideri new genus and species, from the medial Miocene Namba Formation, was found on the western side of Lake Tarkarooloo, South Australia. It is tentatively assigned to the Wynyardiidae and may be the plesiomorphous sister group of the Vombatidae.     

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.