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the Kirthar Formation ranges in age from middleMiddle Eocene to early Late Eocene (Zones P12to P15, 43.6~35.2 Ma). Hence the strata of theKirthar Formation spans in age from early MiddleEocene through early Late Eocene based onrecognition of the planktic foraminiferal ZonesP10 to P15 (49~35.2 Ma).2008040185始 新 世 浮 游 有 孔 虫 Hantkenina 的 起 源 和 形 态学 = Origin and morphology of the Eoceneplanktonic foraminifer Hantkenina. ( 英 文 ). CoxallH K; Huber B T; Pearson P N. Journal ofForaminiferal Research, 2003, 33(3): 237-261 9图 版 .Study of the origin and early evolution of thetubulospine-bearing planktonic foraminiferalgenus Hantkenina reveals that it evolved graduallyfrom the clavate species Clavigerinella eocanicain the earliest middle Eocene and is unrelatedto the genus Pseudohastigerina.Clavigerinella eocanica and the lower middleEocene species Hantkenina nuttalli share manymorphologic features and show similar developmentalpatterns but differ significantly inthese aspects from P. micra. Rare, transitionalClavigerinella-Hantkenina forms from the Helvetikumsection of Austria bridge the gap betweenclavate and tubulospinose morphologies,providing direct, stratigraphically-ordered evidenceof the evolutionary transition betweenHantkenina and Clavigerinella. Clavigerinellidancestry is traced to a previously undescribedlow-trochospiral species, Parasubbotina eoclavasp. nov., at Ocean Drilling Program Site 865.We speculate that Hantkenina originated throughcompetition for limited food resources in a deep,oxygen-deficient habitat below the thermocline.The tubulospines may represent a structural adaptationto this new trophic strategy, allowingthe organism to harvest a greater volume of waterat minimal metabolic cost. The abrupt occurrenceof Hantkenina in pelagic sediment coresfrom the central Pacific and other regions of theworld ocean may represent immigration intothese areas following speciation within the hydrographicallyevolving Tethys Seaway. Alternatively,cladogenesis may have occurred over awider area, but due to a contemporaneous globalhiatus the fossil record of this bioevent is poorlypreserved.2008040186分 子 生 物 学 数 据 揭 示 的 有 孔 虫 Nummulitid科 的 平 行 演 化 = Molecular data reveal parallelevolution in Nummulitid foraminifera. ( 英 文 ).Holzmann M; Hohenegger J; Pawlowski J.Journal of Foraminiferal Research, 2003, 33(4):277-284 1 图 版 .Nummulitidae are the largest extant calcareousForaminifera, and are widely distributed intropical and subtropical shallow-water seas.Classical morphology-based taxonomy dividesthe Nummulitidae in two subfamilies, the Nummulitinaeand Heterostegininae, according to thepresence or absence of secondary septa. To testthe evolutionary importance of this morphologicalfeature, phylogenetic relationships of fiveRecent nummulitid genera were investigated bysequencing fragments of the SSU and LSUrRNA gene. According to our results, speciescharacterized by septate chambers (Heterosteginadepressa, Planostegina operculinoides, andCycloclypeus carpenteri) either group with specieslacking septate chambers (Operculina ammonoides,Nummulites venosus) or branch separately.This suggests that chamber subdivisionsdeveloped several times independently in theevolutionary history of the Nummulitidae, providingan example of parallel evolution in Foraminifera.2008040187得 克 萨 斯 科 罗 拉 多 河 生 境 破 坏 的 有 孔 虫 响 应= Foraminiferal response to habitat disruption:Arroyo Colorado, Texas. ( 英 文 ). Buzas-Stephens P; Pessagno E A. Journal of ForaminiferalResearch, 2003, 33(4): 294-308 1 图版 .In order to assess the possible effects of pollutantson foraminifera along the Texas GulfCoast, sediment cores were taken in four areasconsidered to be at risk: southern Laguna Madre,Nueces Bay, the Arroyo Colorado, and LagunaAtascosa. Geochemical analyses indicate that thesediments are relatively uncontaminated. Foraminiferalanalyses, however, reveal otherwiseundetected inconsistencies and changes withtime. First, though foraminiferal assemblages inthe surface sediments of Laguna Madre, NuecesBay, and Laguna Atascosa are typical, they areatypical in the Arroyo Colorado. In Texas estuarineenvironments, Ammonia often comprises alarge proportion of the assemblage. But in theArroyo Colorado, an estuarine river, the assemblageis almost all Elphidium to the exclusion ofAmmonia. A second observation is that downcorein the Arroyo Colorado cores, Ammoniabecomes abundant as numbers of El-phidiumdecrease. The assemblage at the base of the ArroyoColorado cores is thus more typical for theGulf Coast, while that in the surface sediments isnot. This down-core change in the foraminiferalassemblage is coincident with a change in sedimentgrain size, both most likely due to thedredging of the Harlingen ship channel in thelate 1940s. The reasons why Ammonia, an opportunisticgenus that thrives in a wide range ofenvironmental conditions, was unable to tolerate59