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species is distinct from all other species of thegenus and is included in the “booduga group”. Isuggest that M. dulamensis n. sp. is comparativelymore derived than M. auctor, M. flynni, M.jacobsi and Mus sp. and it may have given riseto M. booduga or M. dunni. It is further suggestedthat presently living M. booduga and M.dunni are more specialized than Mus dulamensisn. sp.2008040480加 勒 比 僧 海 豹 的 绝 灭 速 率 、 历 史 种 群 结 构 和生 态 控 制 = Extinction rate, historical populationstructure and ecological role of the Caribbeanmonk seal. ( 英 文 ). McClenachan L; CooperA B. Proceedings of the Royal Society B:Biological Sciences, 2008, 275(1641): 1351-1358The productivity and biomass of pristine coralreef ecosystems is poorly understood, particularlyin the Caribbean where communities havebeen impacted by overfishing and multiple otherstressors over centuries. Using historical data onthe spatial distribution and abundance of the extinctCaribbean monk seal (Monachus tropicalis),this study reconstructs the population size, structureand ecological role of this once commonpredator within coral reef communities, and providesevidence that historical reefs supportedbiomasses of fishes and invertebrates up to sixtimes greater than those found on typical modernCaribbean reefs. An estimated 233000–338000monk seals were distributed among 13 coloniesacross the Caribbean. The biomass of reef fishesand invertebrates required to support historicalseal populations was 732–1018gm −2 of reefs,which exceeds that found on any Caribbean reeftoday and is comparable with those measured inremote Pacific reefs. Quantitative estimates ofhistorically dense monk seal colonies and theirconsumption rates on pristine reefs provide concretedata on the magnitude of decline in animalbiomass on Caribbean coral reefs. Realistic reconstructionof these past ecosystems is criticalto understanding the profound and long-lastingeffect of human hunting on the functioning ofcoral reef ecosystems.2008040481啮 齿 目 和 古 遗 传 学 : 新 前 景 = Rodents andpalaeogenetics: New perspectives. ( 英 文 ). TougardC; Renvoiséa E. Comptes RendusPalevol, 2008, 7(2/3): 125-134Rodents are the most diversified mammalianorder (484 extant genera including 2277 species),and they have a worldwide distribution. Palaeontological,morphological and molecular datahave greatly helped to resolve their systematicsand evolutionary history. However, some discrepanciesremain between palaeontologists andmolecular biologists. New techniques in molecularbiology, and especially in palaeogenetics,allow us to have direct access to the hereditarymaterial of extinct organisms, and they cancompensate for some morphological limits. Unfortunately,few studies are dealing with rodentpalaeogenetics, despite the amount of museumand fossil material available. Here, we reviewthe major research activities in rodent palaeogenetics(phylogeny, genetic diversity, migration),and we present the promising research perspectivesin this field (phylochronology, palaeoparasitology).2008040482巴 布 新 几 内 亚 高 地 diprotodon 化 石 时 代 可 能是 早 期 的 = A possible early age for a diprotodon(Marsupialia: Diprotodontidae) fossil fromthe Papua New Guinea highlands. ( 英 文 ). MenziesJ; Davies H L; Dunlap W J; Golding SD.Alcheringa, 2008, 32(2): 129 - 147A fossil diprotodon jawbone coated and impregnatedwith a well-cemented fine breccia ortuff was recovered from weakly consolidatedPleistocene lacustrine sediments near Yonki inthe Papua New Guinea highlands. The fine brecciaincludes angular rock and mineral fragmentsderived from country rock, accretionary lapilliand clay minerals. It does not include any identifiableprimary volcanic material. The presenceof accretionary lapilli and lack of volcanic clastssuggests an origin by phreatic eruption—an explosiveeruption driven by the violent escape ofgas. Minerals in the fine breccia have an age of13.2 ± 0.2 Ma, middle Miocene, as indicated by40 Ar/ 39 Ar analysis. This is the age of the countryrock that was blasted by the phreatic eruption.Igneous activity in the Yonki area is thought tohave ceased at 7.4 Ma (younger age limit ofElandora Porphyry; late Miocene), and so it islikely, but not certain, that the phreatic eruptionoccurred not later than 7.4 Ma. The jawbone, asfar as can be told from its poor condition, is dentallysimilar to the late Pliocene and possiblyPleistocene 'Kolopsis' watutense recovered fromother sites in New Guinea. Probably, the jawbone,or the living marsupial, was buried in thefine breccia at the time of the phreatic eruption,and its remains were subsequently reworked byriver erosion and redeposited in the lacustrinesediments. Recrystallization and loss of primarytexture in some of the bone may be a result ofheating at the time of, or preceding, the eruption.2008040483意 大 利 托 斯 卡 纳 地 区 上 新 统 下 部 地 层 新 的 海牛 类 = New sirenian record from Lower Pliocenesediments of Tuscany (Italy). ( 英 文 ). Sorbi145