Purgatorius, an early paromomyid primate (Mammalia)

Fragmentary mandibles of Purgatorius unio Van Valen and Sloan from the Puercan (approximately early Paleocene), Garbani Locality, Montana, preserve associated postcanines. Their morphology indicates that this mammal was an early paromomyid primate and suggests that primate ancestry does not include currently known members of the palaeoryctid and leptictid Insectivora or of the Condylarthra.     

Iguanid lizard from the upper cretaceous of Brazil

Pristiguana brasiliensis, new genus and species, from the Upper Cretaceous Baurú Formation of Brazil, is the oldest fossil referable to the living lizard family Iguanidae. It resembles living primitive South American iguanids in some features, but also shows similarity to members of the related family Teiidae. Iguanid fossils do not appear in North America until the early Eocene, probably by waif dispersal from South America during the late Paleocene or early Eocene. A southern continental (Gondwanan) origin of iguanids is more plausible than the northern one often suggested.     

Paleocene hyracothere from polecat bench formation, wyoming

A lower jaw of an eohippus (Hyracotherium cf. H. angustidens) from late Paleocene strata in Wyoming has extended the geological record of fossil horses into pre-Eocene time and suggests that the order Perissodactyla had an origin earlier than that heretofore conjectured. This specimen, together with equid teeth also possibly of late Paleocene age from Baja California, indicates that early perissodactyls were widespread on the North American continent before the Eocene epoch. Late Paleocene and early Eocene deposits of northwestern Wyoming have yielded many vertebrate rarities and "first or earliest occurrences" which require reappraisals of inter-and intracontinental dispersal patterns of the vertebrate grolups involved.     

Early eocene vertebrates from baja california: evidence for intracontinental age correlations

Newly discovered fossils support a Wasatchian (early Eocene) age for the Punta Prieta vertebrate fauna of Baja California and reveal the utility of land mammal ages on a continental scale. Dispersal scenarios for late Paleocene and early Eocene vertebrates usually invoke heterochrony for similar, but geographically separated, faunas or taxa. Such heterochrony is not supported by independent geochronologies or adequate geographic samples.     

Fossil mammals from baja california: new evidence on early tertiary migrations

Ungulates belonging to the family Barylambdidae were found in the same geologic unit with, but stratigraphically above, a specimen assigned to the Tillodontia and above several molars of the perissodactyl cf. Hyracotherium sp. This arrangement is unusual, as in the well-documented faunas from the Rocky Mountain Region Barylambdidae are known only from the Paleocene, Tillodontia from the Paleocene and Eocene, while Hyracotherium is known only from the Eocene. The expected stratigraphic order would be, from lowest to highest, Barylambdidae, Tillodontia, and Hyracotherium. It is suggested that the Baja California assemblage is late Paleocene on the basis of the generalized molars of cf. Hyracotherium sp. and the characters of cf. Esthonyx sp.     

Paleontology. Shaking the earliest branches of anthropoid primate evolution

Primates living today are believed to share a common ancestor that originated in either Africa or Asia. Fossil examples of such anthropoid ancestors have been found in both continents, so pushing back the origins to a single location has been controversial. In their Perspective, Jaeger and Marivaux discuss results reported in the same issue by Seiffert et al. that may put part of the controversy to rest. Seiffert et al. describe the earliest and most complete African anthropoid fossils from the Fayum desert region of Egypt. Cranial and dental fossils of two different small species were found, and their character, especially the features of the fossil teeth, suggests an ancient evolutionary history in Africa. At the same time, the phylogenetic analysis of Seiffert et al. is consistent with the view that African anthropoids immigrated from Asia at a very early date, probably before the late Paleocene (60 million years ago), possibly followed by later waves of immigration.     

长春市一新外来入侵物种--白蜡虫的生物学特性与种群控制研究

首次报道了白蜡虫在长春市的分布。经观察,白蜡虫在长春市1年发生1代,以受精雌虫在水蜡树枝上越冬。4月中旬雌虫开始活动,5月上旬至5月下旬为卵期,6月上旬卵开始孵化。初孵若虫经1周后在水蜡树叶片上固定取食。2龄若虫在枝条上为害,至8月下旬羽化成虫。雌虫经交尾后越冬。对2龄若虫进行化学防治试验表明,以体积分数为3%顺式氯氰菊酯1:3 000~7 000倍液和40%毒死蜱1:800~1 000倍液进行喷雾防治,防治效果均可达到99%。     

Cenozoic plant diversity in the neotropics

Several mechanisms have been proposed to explain the high levels of plant diversity in the Neotropics today, but little is known about diversification patterns of Neotropical floras through geological time. Here, we present the longest time series compiled for palynological plant diversity of the Neotropics (15 stratigraphic sections, 1530 samples, 1411 morphospecies, and 287,736 occurrences) from the Paleocene to the early Miocene (65 to 20 million years ago) in central Colombia and western Venezuela. The record shows a low-diversity Paleocene flora, a significantly more diverse early to middle Eocene flora exceeding Holocene levels, and a decline in diversity at the end of the Eocene and early Oligocene. A good correlation between diversity fluctuations and changes in global temperature was found, suggesting that tropical climate change may be directly driving the observed diversity pattern. Alternatively, the good correspondence may result from the control that climate exerts on the area available for tropical plants to grow.     

Cretaceous, Paleocene, and Pleistocene Sediments from the Indian Ocean

Two deep-sea cores containing Cretaceous, Paleocene, and Pleistocene sediments from an oceanic rise approximately 500 miles southeast of Cape Town contained well-preserved fossil foraminiferal ooze made up of about 97 percent planktonic forms, including species of Guembelina and Hedbergella. High percentages of particles less than 53 micro in diameter in the Cretaceous and Paleocene sediments indicate a deep-water open-ocean depositional environment. These sediments are the oldest recovered so far from the Indian Ocean.     

Ages of fossil penguins in new zealand

The age of a New Zealand specimen generally believed to represent the oldest known penguin, hitherto considered early Eocene (Heretaungan), has been restudied by the New Zealand Geological Survey and is early Miocene. The oldest known penguins are from the late Eocene. The reported great range of a single species, Palaeeudyptes antarcticus, from late Eocene to late Oligocene or early Miocene (Kaiatan to Waitakian) is not acceptable. Dating of some other specimens is less precise than previously reported.     

Decoupled plant and insect diversity after the end-Cretaceous extinction

Food web recovery from mass extinction is poorly understood. We analyzed insect-feeding damage on 14,999 angiosperm leaves from 14 latest Cretaceous, Paleocene, and early Eocene sites in the western interior United States. Most Paleocene floras have low richness of plants and of insect damage. However, a low-diversity 64.4-million-year-old flora from southeastern Montana shows extremely high insect damage richness, especially of leaf mining, whereas an anomalously diverse 63.8-million-year-old flora from the Denver Basin shows little damage and virtually no specialized feeding. These findings reveal severely unbalanced food webs 1 to 2 million years after the end-Cretaceous extinction 65.5 million years ago.     

Equatorius: a new hominoid genus from the Middle Miocene of Kenya

A partial hominoid skeleton just older than 15 million years from sediments in the Tugen Hills of north central Kenya mandates a revision of the hominoid genus Kenyapithecus, a possible early member of the great ape-human clade. The Tugen Hills specimen represents a new genus, which also incorporates all material previously referable to Kenyapithecus africanus. The new taxon is derived with respect to earlier Miocene hominoids but is primitive with respect to the younger species Kenyapithecus wickeri and therefore is a late member of the stem hominoid radiation in the East African Miocene.     

Mammalian dispersal at the Paleocene/Eocene boundary

A profound faunal reorganization occurred near the Paleocene/Eocene boundary, when several groups of mammals abruptly appeared on the Holarctic continents. To test the hypothesis that this event featured the dispersal of groups from Asia to North America and Europe, we used isotope stratigraphy, magnetostratigraphy, and quantitative biochronology to constrain the relative age of important Asian faunas. The extinct family Hyaenodontidae appeared in Asia before it did so in North America, and the modern orders Primates, Artiodactyla, and Perissodactyla first appeared in Asia at or before the Paleocene/Eocene boundary. These results are consistent with Asia being a center for early mammalian origination.     

Behavior and phylogeny: constriction in ancient and modern snakes

Comparative analyses of behavior have an underappreciated potential for revealing the role of ethoecological factors in the origins of higher taxa. Twenty-seven species (13 genera) in the advanced family Colubridae exhibited 19 patterns of coil application; one or two patterns were usually consistent within a genus. Forty-eight species (26 genera) in the primitive families Acrochordidae, Aniliidae, Boidae, and Xenopeltidae usually used a single pattern, despite differences in age, size, shape, habitat, and diet. This implies the shared retention of an action pattern used by their common ancestor no later than the early Paleocene. Constriction must have been used as a prey-killing tactic very early in the history of snakes and might have been a behavioral "key innovation" in the evolution of their unusual jaw mechanism.     

安徽沿江圩丘农区水稻田杂草区系及草害的研究

本文报道了自１９８５年至１９９０年间，对安徽沿江圩丘农区的６０．４公顷水稻田杂草种群数量调查和大面积的普查结果。共采集标本１０００余份。发现并记载水稻田杂草２８科、４５属Ｊ７４种，田边及回埂杂草２９科、７５属、１４２种，以及２种安徽省植物地理分布新记录种。恶性和区域性恶性稻田杂草有种草、节节菜、鸭舌草、牛毛毡、矮慈菇以及水莎草、眼子菜和猪毛草。早、中稻田的主要杂草群落是稗草十鸭舌草十节节菜十小茨藻，草害较严重；晚稻田则是以节节菜十牛毛毡十鸭舌草十矮慈菇为主，草害较轻。造成早、晚稻田杂草发生差异的主要因素是，栽培措施和生长季节引起的生态因子的不同。因此，该区稻田除草策略是，早稻田除稗、晚稻田除早便发。     

北京树木物候谱

北京树木物候谱是根据作者等十多年观测树木的萌芽、展叶、开花、果熟和落叶等生活周期现象编绘而成。北京树木萌芽始期一般在日平均温度稳定在3℃以上,少数种类在0℃以上即能萌动。树木各物候期因树种不同而有差异,但有一定的顺序性。树木各物候期,特别是早春各物候期与活动积温关系极为密切。北京29种树木物候谱可分为三类九型。从各物候谱的类型可以了解各树种物候学特性的共性和差异,进而了解各树种的生物学和生态学特性,对林业生产有很重要的实践意义。对农、医和生物学工作者也有一定参考价值。     

Calibration of the beginning of the age of mammals in patagonia

Beds of the Rio Chico Formation containing the earliest known land mammals in Patagonia, southern Argentina, were calibrated by potassium-argon age determinations and paleomagnetic polarity data. The Riochican land mammal age encompasses the middle and late Paleocene and corresponds in time with Torrejonian and Tiffanian land mammal faunas in North America.     

松瘿小卷蛾生物学特性的研究

松瘿小卷蛾Ｌａｓｐｅｙｒｅｓｉａ ｚｅｂｅａｎａ（Ｒａｔｚ）是落叶松人工林一种重要的枝梢害虫。在黑龙江省两年发生一代，跨３个年度。当年和翌年９月未或１０月初分别以幼龄幼虫和老龄幼虫越冬，第３年度５月初开始化蛹；５月下旬开始羽化，５月末开始产卵，６月中，下旬幼虫孵化。幼虫期有两种寄生蜂，寄生率为２５％左右。     

Disturbance and ecologic succession in an upper ordovician cobble-dwelling hardground fauna

An Ordovician hardground fauna in northern Kentucky provides an example from the fossil record of the maintenance of species diversity by periodic disturbance of an autogenic ecologic succession. The marine invirtebrates found encrusting limestone cobbles show an order of community development from a low-diversity pioneer assemblage through a high-diversity association to a monospecific stable fauna. All species, including the late successional dominants, were present in the early stages of colonization. Periodic overturning of the cobbles killed the encrusters and opened up new spaces on which succession was reinitiated. These disturbances maintained high diversity within the encrusting community by limiting the spatial distribution of the most efficient space competitors.     

新疆早熟中长绒棉育种进展特点及改进目标

据国家、新疆早熟棉区试验结果分析:"十五"期间新疆早熟中长绒棉育种取得新进展,有两个新品种通过2003～2007品种审定,在生产上示范推广,一批新品系参试.新品种(系)产量水平接近常规推广品种,纤维品质基本符合农业部2003～2007年中长绒棉育种目标,抗病性在逐步提高,同时存在熟性偏晚,吐絮不集中,中后期花成熟度差,抗逆、适应性不强等问题.提出了提高早熟性、强力和抗逆为重点的育种目标和扩大遗传背景,打破性状间负相关性及田间目标性状选择等改良措施.