Journal of Human Evolution最新文献

The genus Macaca includes medium- to large-bodied monkeys and represents one of the most diverse primate genera, also having a very large geographic range. Nowadays, wild macaque populations are found in Asia and Africa, inhabiting a wide array of habitats. Fossil macaques were also present in Europe from the Late Miocene until the Late Pleistocene. Macaques are considered ecologically flexible monkeys that exhibit highly opportunistic dietary strategies, which may have been critical to their evolutionary success. Nevertheless, available ecological information regarding fossil European species is very sparse, limiting our knowledge of their evolutionary history in this geographic area. To further our understanding of fossil European macaque ecology, we investigated the dietary ecology of Macaca majori, an insular endemic species from Sardinia. In particular, we characterized the dental capabilities and potential dietary adaptations of M. majori through dental topographic and enamel thickness analyses of two M²s from the Early Pleistocene site of Capo Figari (1.8 Ma). We also assessed its diet through dental microwear texture analysis, while the microwear texture of M. majori was also compared with microwear textures from other European fossil macaques from mainland Europe. The dental topographic and enamel thickness analyses suggest that M. majori frequently consumes hard/mechanically challenging and/or abrasive foods. The results of the dental microwear analysis are consistent with this interpretation and further suggest that M. majori probably exhibited more durophagous dietary habits than mainland Plio-Pleistocene macaques. Overall, our results indicate that M. majori probably occupied a different dietary niche compared to its mainland fossil relatives, which suggests that they may have inhabited different paleoenvironments.

Ekgmowechashala is a poorly documented but very distinctive primate known only from the late early Oligocene (early Arikareean) of western North America. Because of its highly autapomorphous dentition and spatiotemporal isolation, the phylogenetic and biogeographic affinities of Ekgmowechashala have long been debated. Here, we describe the oldest known fossils of Ekgmowechashala from the Brown Siltstone Beds of the Brule Formation, White River Group of western Nebraska. We also describe a new ekgmowechashaline taxon from the Nadu Formation (late Eocene) in the Baise Basin of Guangxi Zhuang Autonomous Region in southern China. Phylogenetic analysis suggests that North American Ekgmowechashala and the new Chinese taxon are sister taxa that are nested within a radiation of southern Asian adapiforms that also includes Gatanthropus, Muangthanhinius, and Bugtilemur. The new Chinese ekgmowechashaline helps fill the considerable disparity in dental morphology between Ekgmowechashala and more primitive ekgmowechashalids known from southern Asia. Our study underscores the fundamental role of southern Asia as a refugium for multiple primate clades during the cooler and drier climatic regime that prevailed after the Eocene–Oligocene transition. The colonization of North America by Ekgmowechashala helps define the beginning of the Arikareean Land Mammal Age and corresponds to an example of the Lazarus effect, whereby a taxon (in this case, the order Primates) reappears suddenly in the fossil record after a lengthy hiatus.

The Initial Upper Paleolithic (IUP) is one of the most important phases in the recent period of the evolution of humans. During a narrow period in the first half of Marine Isotope Stage 3 laminar industries, accompanied by developed symbolism and specific blade technology, emerged over a vast area, replacing different variants of the Middle Paleolithic. In western Eurasia, the earliest appearance of IUP technology is seen at the Boker Tachtit site, dated ca. 50 ka cal BP. The earliest evidence of IUP industries in the Balkans and Central Europe, linked to the spread of Homo sapiens, has been dated to around 48 ka cal BP. A key area of IUP dispersals are the mountains and piedmont of southern Siberia and eastern Central Asia. One of the reference assemblages here is Kara-Bom, an open-air site in the Siberian Altai. Three major settlement phases are distinguished in the sediment sequence. In this paper, we present the results of new radiocarbon determinations and Bayesian models. We find that the latest phase of the IUP, Upper Paleolithic 1 (‘UP1’) is bracketed between 43 and 35 ka cal BP (at 95.4% probability). The earliest IUP phase, ‘UP2’, begins to accumulate from ca. 49 ka cal BP and ends by ca. 45 ka cal BP. The Middle Paleolithic ‘MP2’ assemblages all fall prior to 50 ka cal BP. We can detect a spatial distribution of dates from the geographic core of the IUP beyond the Altai where it appears around 47–45 ka cal BP. The current distribution of dates suggests a west–east dispersal of the IUP technocomplex along the mountain belts of Central Asia and South Siberia.

Although the ‘organization of space’ is said to be one of the defining characteristics of modern human behavior, the identification and documentation of such organization has proven to be elusive, especially as rendered in artifact patterning. Without directly comparing artifact patterns within multiple sites, there is no benchmark with which to conclude one site to be more or less ‘organized’ than another. We can objectively identify patterns within the distribution of archaeological materials, but the decision of whether that patterning constitutes as ‘organized’ is entirely subjective without a comparative model. In this paper, I present the results of a study in which the spatial distribution of artifacts within nine Middle and Upper Paleolithic sites in France are directly compared to one another, and discernible changes in patterning can be identified. The differences in spatial patterning between the Middle and Upper Paleolithic sites suggest that the organization of space likely became increasingly formalized into and throughout the Upper Paleolithic alongside other cultural norms of behavior. Though more sites are needed to thoroughly document this phenomenon, this study suggests that direct comparisons of spatial patterning have the potential to yield more objective results on the question of spatial organization.

Hispanopithecus laietanus from the Late Miocene (9.8 Ma) of Can Llobateres 1 (CLL1; Vallès-Penedès Basin, NE Iberian Peninsula) represents one of the latest occurrences of fossil apes in Western mainland Europe, where they are last recorded at ∼9.5 Ma. The paleoenvironment of CLL1 is thus relevant for understanding the extinction of European hominoids. To refine paleoenvironmental inferences for CLL1, we apply ecometric models based on functional crown type (FCT) variables—a scoring scheme devised to capture macroscopic functional traits of occlusal shape and wear surfaces of herbivorous large mammal molars. Paleotemperature and paleoprecipitation estimates for CLL1 are provided based on published regional regression models linking average FCT of large herbivorous mammal communities to climatic conditions. A mapping to Whittaker's present-day biome classification is also attempted based on these estimates, as well as a case-based reasoning via canonical variate analysis of FCT variables from five relevant biomes. Estimates of mean annual temperature (25 °C) and mean annual precipitation (881 mm) classify CLL1 as a tropical seasonal forest/savanna, only in partial agreement with the canonical variate analysis results, which classify CLL1 as a tropical rainforest with a higher probability. The former biome agrees better with previous inferences derived from fossil plants and mammals, as well as preliminary isotopic data. The misclassification of CLL1 as a tropical forest is attributed to the mixture of forest-adapted taxa with others adapted to more open environments, given that faunal and plant composition indicates the presence of a dense wetland/riparian forest with more open woodlands nearby. The tested FCT ecometric approaches do not provide unambiguous biome classification for CLL1. Nevertheless, our results are consistent with those from other approaches, thus suggesting that FCT variables are potentially useful to investigate paleoenvironmental changes through time and space—including those that led to the extinction of European Miocene apes.