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Abstract: Weeds with broad distributions and large morphological variation are challenging for systematists and evolutionarily intriguing because their intensive dispersal would likely prevent local morphological differentiation. Study on weeds will help to understand divergence in plants unlikely to be affected by geographical and ecological barriers. We studied Youngia japonica based on nrDNA and cpDNA sequences. This is a widespread native in Asia and invasive worldwide; nevertheless, three subspecies (japonica, longiflora, and formosana) and an undescribed variant occur in Taiwan. Bayesian and the most parsimonious phylogenies revealed that subspecies longiflora is a different linage and independently arrived in Taiwan during the Pleistocene via land connection to the Asian Continent. Bayesian time estimation suggested that Youngia in Taiwan diverged in the lower Pleistocene or more recently. Extreme habitats that emerged in the Pleistocene, i.e., cold mountain ranges for subspecies formosana and xeric, raised coral reefs for the undescribed Youngia variant probably had triggered the divergence. Components of Youngia in Taiwan are not monophyletic; a coalescent-based test suggested incomplete lineage sorting. Nevertheless, the samples within each taxon share unique morphological features suggesting a common gene pool and each taxon has different dominant ITS and/or cpDNA types; these conditions suggest ongoing process toward monophyly via coalescent processes and support the delimitation of intraspecific taxa. [Copyright &y& Elsevier]

Abstract: The small mammal accumulations in the Pleistocene deposits of Karain Cave are investigated to identify the predators and possible biases in the fossil assemblages. Seven small mammal assemblages are studied in chronological order from two chambers of the cave, the main chamber E and the side chamber B. The lowermost level within the whole sequence is Proto-Charentien, which corresponds to an early stage of the Middle Palaeolithic. The main part of the material belongs to Middle Palaeolithic layers. The most important aspect of the fossil record in the cave is the human occupation without any interruption through the Pleistocene to Holocene. The small mammal fossil evidence in the cave denotes the presence of opportunistic predators throughout the sequence with one exception, and these produce balanced samples of small mammal faunas in the habitat. The lack of bias in the small mammal faunas allow the interpretation of local environments, showing that partial steppe and arid conditions existed during deposition of the lowermost levels of the Middle Palaeolithic in Karain Cave and that these shifted into more temperate and wooded habitat in the upper levels. Evidence from the side chamber indicates some differences, with a more open grassy environment. In the Mediterranean part of Anatolia the temperate and moist conditions in the Middle Palaeolithic were superseded by more arid conditions in the Upper Palaeolithic, followed by a decrease in steppe conditions during the Epi-Palaeolithic period. [Copyright &y& Elsevier]

Abstract: Our knowledge of early Australasian societies has significantly expanded in recent decades with more than 220 Pleistocene sites reported from a range of environmental zones and depositional contexts. The uniqueness of this dataset has played an increasingly important role in global debates about the origins and expression of complex behaviour among early modern human populations. Nevertheless, discussions of Pleistocene behaviour and cultural innovation are yet to adequately consider the effects of taphonomy and archaeological sampling on the nature and representativeness of the record. Here, we investigate the effects of preservation and sampling on the archaeological record of Sahul, and explore the implications for understanding early cultural diversity and complexity. We find no evidence to support the view that Pleistocene populations of Sahul lacked cognitive modernity or cultural complexity. Instead, we argue that differences in the nature of early modern human populations across the globe were more likely the consequence of differences in population size and density, interaction and historical contingency. [Copyright &y& Elsevier]

Abstract: Australia and New Guinea share a common biogeographical history and unique vertebrate fauna. Investigation of genetic relationships among the wet forest-restricted pademelons (Macropodidae: Thylogale) provides insight into the historical connections between the two regions and the evolution of the Australasian marsupial fauna. Molecular phylogenetic relationships among Thylogale species were analysed using mitochondrial (12S rRNA and cytochrome b) and nuclear (omega-globin intron) sequence data with Bayesian and maximum likelihood methods. Australian species were resolved as well-supported, monophyletic clades, whereas endemic New Guinean species did not form clades consistent with current morphological taxonomy. Estimates of divergence using a Bayesian relaxed molecular clock model with standard mammalian nucleotide substitution rates indicated radiation of the genus in Australia in the mid to late Miocene. Persistence of Australian species of Thylogale in both southern temperate and northern tropical forests throughout the drying of the Australian continent can be attributed to their having a greater dietary flexibility than other browsing forest macropods. Divergence of the endemic New Guinean lineage occurred in the late Miocene to early Pliocene, indicating the presence of a partially forested landbridge connecting Australia and New Guinea during the Miocene. Mid-Pleistocene divergence between subspecies of the trans-Torresian T. stigmatica implies gene flow during glacial maxima between forest populations in the southern lowlands of New Guinea and the northern Cape York region of Australia. Complex structuring and relatively limited differentiation among populations of the endemic New Guinean species appears to have been influenced by the uplift of land and climate-induced redistribution of forest habitats during the late Pliocene and Pleistocene period. This is in strong contrast to the long evolutionary history and comparatively deep genetic divergence of Thylogale species in Australia. Further evaluation of the species status of the New Guinean Thylogale using more informative nuclear markers and extensive sampling is required. [Copyright &y& Elsevier]

Abstract: There has been a protracted debate over the evidence for intentional cranial modification in the terminal Pleistocene Australian crania from Kow Swamp and Coobool Creek. Resolution of this debate is crucial to interpretations of the significance of morphological variation within terminal Pleistocene–early Holocene Australian skeletal materials and claims of a regional evolutionary sequence linking Javan Homo erectus and Australian Homo sapiens. However, morphological comparisons of terminal Pleistocene and recent Australian crania are complicated by the significantly greater average body mass in the former. Raw and size-adjusted metric comparisons of the terminal Pleistocene skeleton from Nacurrie, south-eastern Australia, with modified and unmodified H. sapiens and H. erectus, identified a suite of traits in the frontal, parietal, and occipital bones associated with intentional modification of a neonate’s skull. These traits are also present in some of the crania from Kow Swamp and Coobool Creek, which are in close geographic proximity to Nacurrie, but not in unmodified H. sapiens or Javan H. erectus. Frontal bone morphology in H. erectus was distinct from all of the Australian H. sapiens samples. During the first six months of life, Nacurrie’s vault may have been shaped by his mother’s hands, rather than though the application of fixed bandages. Whether this behaviour persisted only for several generations, or hundreds of years, remains unknown. The reasons behind the shaping of Nacurrie’s head, aesthetics or otherwise, and why this cultural practice was adopted and subsequently discontinued, will always remain a matter of speculation. [ABSTRACT FROM AUTHOR]

Abstract: In 2001, a portion of human frontal bone was discovered in sediments extracted from the bottom of the North Sea, 15km off the coast of the Netherlands. The extraction zone is located in the so-called Zeeland Ridges area located at 51°40′ northern latitude and 3°20′ eastern longitude. The specimen was dredged up from sediments containing Late Pleistocene faunal remains and Middle Palaeolithic artefacts, including well-finished small handaxes and Levallois flakes. The details of the supraorbital morphology, as well as the quantitative assessment of the shape of the external surface of the squama using traditional and 3D geometric morphometrics, unambiguously assign the Zeeland Ridges frontal bone to Homo neanderthalensis. Carbon and nitrogen isotopic analysis indicate that the Zeeland Ridges hominin, like other Neandertals, was highly carnivorous and does not show evidence for the consumption of aquatic foods. A lesion on the outer table and diploic layer of the bone in the area of the supratoral sulcus can be interpreted as the result of an intradiploic epidermoid cyst, a type of neoplasm diagnosed for the first time in Neandertal remains. So far, the Zeeland Ridges Neandertal is the first Pleistocene fossil hominin found under seawater and the first recorded in the Netherlands. [Copyright &y& Elsevier]

Abstract: The combination of large samples and broken material raises practical issues and potential problems that may be undetectable in smaller samples. Informal identification keys are provided to indicate the types of non-dental features that may be usefully employed when standard features are not present. This process has so far been taken to the generic level. The ratio of minimum numbers of individuals based on mandibles alone (MD) to those obtained using mandibles and maxillae (MNI) varies from 0.59 in Gerbillinae to 0.97 in Macroscelididae, thereby demonstrating that counting only mandibles will skew sample structure. Differential difficulty of identification at lower taxonomic levels, combined with differential susceptibility to breakage, also influences the likelihood that the proportional representation of taxa will be correct. [Copyright &y& Elsevier]

Vicariant and climatic cycling speciation hypotheses of the ‘sand gobies’ belonging to the genera Pomatoschistus, Gobiusculus, Knipowitschia, and Economidichthys are tested using molecular phylogenies constructed of nuclear DNA (ITS1 locus) and mitochondrial DNA (12S and 16S fragments). These gobies are among the most abundant in the Eastern Atlantic-Mediterranean region, and play an important role in the ecosystem. Considerable ITS1 length differences, primarily due to the presence of several tandem repeats, were found between species and even within individuals. Therefore, phylogenetic analyses focused on fragments of the 12S and 16S mtDNA region that have been sequenced for 16 goby taxa. The ‘sand gobies’ clustered as a monophyletic group as proposed on morphological grounds. However, G. flavescens, E. pygmaeus, and K. punctatissima clustered within the Pomatoschistus species, pointing to a paraphyletic origin of these genera. Furthermore, the genetic divergence between P. minutus from the Adriatic Sea versus the Atlantic-Mediterranean region was as high as the divergence within the P. minutus complex, suggesting that P. minutus from the Adriatic Sea should be considered as a distinct species. The “star” phylogeny might suggest that these gobies evolved in a very short time period, possibly linked to the drastic alterations in the Mediterranean Sea during and immediately after the Messinian salinity crisis at the end of the Miocene. The freshwater life-style appeared monophyletic; equating its origin with the salinity crisis resulted in a molecular clock estimate of 1.4% divergence per million years. The last common ancestor probably occupied sandy bottoms and a coastal niche while several species subsequently adapted to new habitats (pelagic, freshwater or stenohaline). The origin of the shallowest clades dated back to the glacial cycling during the Pleistocene epoch. [Copyright &y& Elsevier]

From a detailed analysis of published and unpublished sources, we constructed a digitized three-dimensional, stratigraphically-controlled excavation grid of Zhoukoudian Locality 1 in order to assess the spatial relationships of the excavated materials. All 15 fossil Homo erectus loci were mapped on the grid. Meter cubes were used in excavation starting in 1934, and Loci H through O, established between 1934 and 1937, were mapped to within 1 m3vertical and horizontal provenience. Loci A through G, established between 1921 and 1933, were excavated in the northernmost part of Locality 1 by unmapped quarrying, but their stratigraphic levels were recorded. We could localize Loci A through G on the grid system by utilizing locations of remaining walls, stratigraphic sections, excavation reports, excavation maps, and photographs. Loci contained skeletal elements of Homo erectus individuals scattered over areas of the cave floor of up to 9 m in diameter. Scoring of taphonomic damage on the Homo erectus sample, as observed on casts and originals, demonstrates that 67% of the hominid sample shows bite marks or other modifications ascribed to large mammalian carnivores, particularly the large Pleistocene cave hyena, Pachycrocuta brevirostris. Virtually all of the remaining Homo erectus skeletal assemblage shows breakage consistent with this taphonomic pattern of fragmentation. Bioturbation by digging carnivores is the most likely explanation for a fragment of Homo erectus Skull XI discovered 1 m below its other conjoined portions in Locus L. Carbon on all the Homo erectus fossils from Locus G, a circumscribed area of 1-meter diameter, earlier taken to indicate burning, cooking, and cannibalism, is here interpreted as detrital carbon deposited under water, perhaps the result of hyaenid caching behavior. Locus G records the close stratigraphic and horizontal association of stone artifacts with Homo erectus and other vertebrate skeletal elements, an association that is seen at other loci as well. Layer 4 of the excavation contains equid cranial bone previously interpreted to have been burned while fresh. We here document that Locus B Homo erectus, including Skull I, is stratigraphically associated with this evidence, but at some 10–12 m distance. Even though the presence of wood-stoked fires and hearths is not supported by geochemical results, evidence of fire at Locality 1 in the form of burned bone is confirmed. Contextual relationships of fossil skeletal elements, relationships of carnivore damage and stone tool cutmarks on bone, and evidence of the burning of fresh bone associated with Homo erectus and stone tools support a model of transient hominid scavenging aided by the use of fire at the large hyenid den that became Zhoukoudian Locality 1. Although the original excavation catalogue from Locality 1, as well as a significant number of fossils and stone artifacts, were lost during World War II, catalogue numbers on the many surviving specimens can be used to locate fossils and artifacts within the three-dimensional grid provided in this paper. [Copyright &y& Elsevier]

The spring peeper (Pseudacris crucifer) is believed to have been a primary herpetological invader of eastern North America following the most recent period of glacial retreat. We examined the phylogeographic pattern and population structure of P. crucifer to determine whether the distribution of haplotypic variants reflect post-Pleistocene recolonization dynamics. A number of geographically isolated evolutionary lineages were supported by both maximum parsimony and neighbor-joining analyses, and by coalescence approaches applied to mtDNA. South-western Ontario represents a high level of genotypic diversity (π) due to the presence of two divergent lineages. The geographic distribution of these lineages are interpreted as reflecting post-glacial recolonization dynamics from separate, isolated refugia during the late Pleistocene that have come into secondary contact in SW Ontario. The phylogenetic placement of haplotypes from the range of P. crucifer bartramiana (Florida and South Carolina) does not allow for monophyly of P. crucifer crucifer, and therefore the bartramiana subspecies designation does not reflect a separate evolutionary lineage. [Copyright &y& Elsevier]