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1.
The early Oligocene Boom Formation in Belgium yielded many avian remains from the Rupelian unit-stratotype, most of which have remained unstudied so far. Here, I describe a small loon (Gaviiformes) and a new species of large owl (Strigiformes) that are represented by associated bones of a single individual each. The loon, of which wing and pectoral girdle bones are preserved, is assigned to Colymboides (?) metzleri, a species previously known from a partial skeleton from the Rupelian of Germany. The owl is based on a tarsometatarsus and distal tibiotarsus and described as a new species, Selenornis steendorpensis. It constitutes the most substantial fossil record of the taxon Selenornis, which was before known from a distal tibiotarsus from an unknown horizon of the Quercy fissure fillings in southwestern France. It is detailed that there are differences in the higher level taxonomic composition of the known early Oligocene avifaunas of northern and southern Europe, which may reflect true zoogeographic facts owing to a different climate and vegetation.  相似文献   

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3.
Common loons (Gavia immer) are top predators that are sensitive to biotic and abiotic conditions associated with their breeding lakes, so factors such as lake chemistry and human activity or disturbance are thought to influence their seasonal and long-term reproductive success. We used two indices of loon productivity to evaluate (1) temporal patterns and (2) relationships with physical and chemical lake characteristics and human activities. Data collected from 1991 to 2000 by volunteers of the Canadian Lakes Loon Survey (CLLS) in Nova Scotia showed that loon productivity, as indexed by both the proportion of resident pairs that produced at least one large young (Ps1) and the proportion of successful pairs that produced two large young (Ps2), did not vary substantially from year to year and showed no linear trend from 1991 to 2000. Average estimates (1991–2000) for Ps1 and Ps2 were 0.49 ± 0.02 and 0.43 ± 0.03, respectively, and the mean number of chicks per residential pair over that time was 0.75 ± 0.04. We found that human disturbance and shoreline development did not influence loon productivity during the prefledging stage on lakes surveyed by CLLS volunteers. Proportion of resident pairs rearing at least one large young was independent of dissolved organic carbon (DOC) concentrations of breeding lakes, but there was a positive relationship between the proportion of successful pairs rearing two large young and DOC. Both indices of loon productivity tended to be negatively correlated with lake pH. These results were not consistent with other findings that loon productivity generally declines with lake acidity, but likely reflect the preponderance of circumneutral (pH 6.5–7.0) lakes surveyed by the CLLS volunteers in Nova Scotia.  相似文献   

4.
The major radiation of theJuglandaceae occurred during the early Tertiary as recorded by the proliferation of juglandaceous pollen and the appearance of fruits representing extinct and extant genera of the family. Juglandaceous pollen types of the Paleocene were predominantly triporate and exhibited a greater diversity in patterns of exinous thinning than occurs in the family today. Analyses of in situ pollen from early Tertiary juglandaceous inflorescences confirms the taxonomic value of certain patterns of exinous thinning. Data from co-occurring fruits and pollen indicate that relatively unspecialized, isopolar triporate pollen of the type presently confined to the tribeEngelhardieae also occurred in other tribes of the family during the Paleocene. Pollination has been mostly anemophilous throughout the Tertiary. Both wind and animal fruit-dispersal syndromes were established early in the radiation of the family but a greater diversity of wind-dispersed genera has prevailed.  相似文献   

5.
Three new species and one new genus of dicotyledonous woods,Chilechicoxylon microporosum gen. et sp. nov.,Proteoxylon patagonicum sp. nov. andLaurinium beilschmiedioides sp. nov., are described from the Tertiary (or in case of the first and last species from the Cretaceous-Tertiary) of Chile Chico, XI Region, Chile. Previously only wood of temperate species has been identified from Patagonia.Proteoxylon patagonicum (Proteaceae) is the first recorded tropical wood species from this geographical area. Consecutive number from the previous paper (M. Nishida, H. Nishida and T. Nasa, 1988). Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 120 and contributions from Chiba University Botanical Expedition to the Andes No. 20. Supported by a Grant-in-Aid for Overseas Scientific Research from the Ministry of Education, Science and Culture Nos. 61041015 and 63041034.  相似文献   

6.
New trogons from the early Tertiary of Germany   总被引:3,自引:0,他引:3  
GERALD MAYR 《Ibis》2005,147(3):512-518
A new trogon (Aves, Trogoniformes), Primotrogon? pumilio sp. nov., is described from the Middle Eocene (49 Ma) of Messel in Germany. It is the first articulated skeleton of an Eocene trogon, of which only very few fragmentary remains were hitherto known. It is also the earliest complete skeleton of a trogon, exceeding previous finds (Primotrogon wintersteini Mayr 1999) by at least 15 million years. An isolated wing of a trogon is further identified from the early Oligocene (about 30–34 Ma) of the fossil site Frauenweiler in Germany. Primotrogon? pumilio and all other sufficiently well‐preserved early Tertiary trogons appear to be stem group representatives of the Trogoniformes, corresponding with molecular clock data indicating a mid‐Tertiary origin of crown group Trogoniformes.  相似文献   

7.
Cyclamen somalense Thulin & Warfa, spec. nova, the first member of the genus known from tropical Africa, is described from the Al Miskat Mts in NE. Somalia. The new species is closely related to the E. MediterraneanC. persicum Mill. The disjunct Mediterranean element in the mountain flora of northern Somalia, to whichC. somalense belongs, is believed to be largely a relict of Tertiary origin.  相似文献   

8.
The evolution of the Australian flora through the Tertiary has not been reviewed by a megafossil palaeobotanist for almost a century. Based on material available and published studies, the Australian Tertiary can be considered in three units: Eocene, Oligo-Miocene, and Pliocene. Key taxa in the Eocene includeCasuarinaceae, Proteaceae, Fagaceae, Podocarpaceae, andLauraceae. Many known Eocene deposits are interpreted as warm, humid rainforests.Oligo-Miocene floras reflect a climatic deterioration, with greater occurrence of sclerophylly and xerophylly. A reduction of tropical taxa is seen with an increase ofMyrtaceae and earliest records ofMimosaceae, Chenopodiaceae, andPoaceae. These trends continue into the Pliocene, which is not well represented in Australia.Problems needing to be addressed include the discrepancy between the pollen and megafossil records ofNothofagus, the origins of Australia's wet tropical taxa, and the role of fire in the early evolution of the Australian flora.  相似文献   

9.
The fossil coprolite ichnogenusPalaxius is known with 22 species from the Permian up to the Tertiary. The diagnostic characteristics and the stratigraphie range of all species is given in this paper. The ichnogenusAgantaxia Kristan-Tollmann is a younger synonym of the ichnogenusPalaxius. The new crustacean coprolitePalaxius hydranensis n. sp. is described from the reef limestones of Norian part of “Pantokrator” limestone of the Island Hydra (Greece). This is the first report of coprolites from Hydra. The organism association of coprolite bearing limestone is mentioned.   相似文献   

10.
Phyllactinia is a unique genus within the Erysiphales (Ascomycota) having a partly endo-parasitic nature of the mycelium within the host plant tissues. We constructed phylogenetic trees for the genus Phyllactinia and its allied genera based on a total of 120 nucleotide sequences of the 28S rDNA and ITS regions to discuss their phylogenetic relationships with special references to host plants, biogeography, evolutionary dating, and taxonomy. The analysis of the Erysiphales confirmed the monophyly of the endo-parasitic genera, i.e. Leveillula, Phyllactinia, and Pleochaeta. Phyllactinia specimens used in this study were divided into six distinctive groups and three subgroups. Interestingly, Leveillula, an obligately endo-parasitic genus of the Erysiphales, grouped together with Phyllactinia, although this was not significantly supported by the Kishino–Hasegawa and Shimodaira–Hasegawa tests. This suggests that the evolution within this group of fungi occurred from partial endo-parasitism to obligate endo-parasitism. The host range of Phyllactinia is mostly confined to woody plants, especially deciduous trees. Betulaceae, Fagaceae, Ulmaceae, Moraceae, and Rosaceae may have close connections to the divergence of the groups and subgroups of Phyllactinia concerned. Most of these plant families are known as major members of the boreotropical flora of the Tertiary, which suggests an early Tertiary origin of this genus. A comparison of the phylogenies of hosts and parasites revealed that host range expansion at higher taxonomic levels (higher than family level) is independent of the phylogeny of plants. Conversely, host range expansions in lower taxonomic levels (infrafamilial or infrageneric) tend to occur within a single family or genus. An estimation of the evolutionary timing using a molecular clock approach suggested that Phyllactinia split from Pleochaeta about 60 M years ago (Ma) in the early Tertiary and divergence of the six major clades of Phyllactinia occurred between 5 and 40 Ma during the Oligocene and Miocene. Divergence within the major clades and within Leveillula occurred maybe from more than 5 Ma onwards during the Pliocene and Quaternary. This is the first comprehensive phylogenetic study of Phyllactinia and other endo-parasitic genera of the Erysiphales.  相似文献   

11.
Common loons (Gavia immer) are diving waterbirds that are particularly challenging to keep in captivity due to their specific behavioral and physiologic needs, special housing requirements, and susceptibility to stress-related disease. We report a novel method for housing and captive rearing common loon chicks that was developed as part of the first-ever loon translocation effort in southeast Massachusetts, from 2015 to 2017. Thirteen loon chicks were reared in aquatic pens in a natural lake environment, utilizing noninvasive feeding and monitoring techniques that avoided human habituation. Chicks were reared in aquatic pens for 16–28 days before being released onto the lake. All chicks remained clinically normal and were monitored on the lake for up to 4 months following release. At least four of the chicks were subsequently confirmed to have survived to adulthood when they returned to the area in breeding plumage two to 3 years following release. Two of these confirmed adults displayed prolonged territorial pair behavior together, and this is an encouraging early sign that captive-reared individuals may form successful breeding pairs in the future. Because most immature loons remain on the ocean until at least 3 years of age, we expect additional captive-reared loons to return to the release area in subsequent years. These husbandry techniques could be applied to other loon and diving bird species that are notoriously difficult to house in captivity. The novel feeding techniques described here could also be adapted for loon chicks being reared in pools or other traditional captive settings.  相似文献   

12.
The parasitic relationship between a black fly, Simulium annulus, and the common loon (Gavia immer) has been considered one of the most exclusive relationships between any host species and a black fly species. To test the host specificity of this blood‐feeding insect, we made a series of bird decoy presentations to black flies on loon‐inhabited lakes in northern Wisconsin, U.S.A. To examine the importance of chemical and visual cues for black fly detection of and attraction to hosts, we made decoy presentations with and without chemical cues. Flies attracted to the decoys were collected, identified to species, and quantified. Results showed that S. annulus had a strong preference for common loon visual and chemical cues, although visual cues from Canada geese (Branta canadensis) and mallards (Anas platyrynchos) did attract some flies in significantly smaller numbers.  相似文献   

13.
Summary A new species and genus of mousebird (Coliiformes: Coliidae) from the Oligocene (Rupelian) of Frauenweiler near Wiesloch (Baden-Württemberg, Germany) is described.Oligocolius brevitarsus n. gen. n. sp. is the first Oligocene mousebird and one of the most complete skeletons of early Tertiary Coliidae to have come to light so far. The new taxon has a more strongly developed wing and a much shorter tarsometatarsus than recent mousebirds and was probably adapted to a more sustained flight.
Ein neuer Mausvogel (Coliiformes: Coliidae) aus dem Oligozän Deutschlands
Zusammenfassung Eine neue Gattung und Art der Mausvögel (Coliiformes: Coliidae) wird aus dem Oligozän (Rupel) von Frauenweiler bei Wiesloch (Baden-Württemberg, Deutschland) beschrieben.Oligocolius brevitarsus n. gen. n. sp. ist der erste oligozäne Mausvogel und eines der vollständigsten Skelette frühtertiärer Coliidae, das bisher gefunden wurde. Das neue Taxon hat einen kräftiger entwickelten Flügel und einen viel kürzeren Tarsometatarsus als rezente Mausvögel und war wahrscheinlich an einen Flug angepaßt, der ausdauernder als bei rezenten Arten war.
  相似文献   

14.
Abundant archaeological evidence of the occurrence of the endocarp of the oil palm,Elaeis guineensis, in the rain forest and woodland savanna zones of west and central Africa from about 5000 B.P. has shown the tree to be an important element in the subsistence economy of the region; its pollen also has been recorded in most of the regional terrestrial sediments studied so far. The distinct and consistently sudden and more marked increases in this pollen during the late Holocene when compared with the late Tertiary and late Pleistocene frequencies strongly indicate that the late Holocene upsurges were due to both natural and human factors favourable for the expansion of this heliophytic tree. Reasons are given for suggesting that upsurges in oil palm pollen during the late Holocene period in this region can be used as indices of plant cultivation. While the oil palm is known from early Tertiary deposits in west Africa, its earliest palynological record from terrestrial sediments in the west central part dates back only to the early Holocene. More palynological studies of Tertiary and Quaternary terrestrial cores are required to establish with more certainty the antiquity ofE. guineensis in west central Africa.  相似文献   

15.
There are few fossil remains that are assigned or compared toCitrus. A new and characteristic leaf from the Pliocene of Italy is described asCitrus meletensis and its systematic position within theRutaceae is discussed. Together with other sparse remains that are reviewed here it confirms the existence ofCitrus in the European Tertiary.  相似文献   

16.
Abstract: Bioaccumulation of toxic environmental mercury may affect the vital rates of piscivores such as the common loon (Gavia immer). Although immediate effects of mercury on early development or reproduction can be determined from short-term field studies or dosing experiments, long-term effects on survival for a long-lived species such as the common loon must be discerned from large, long-term observational data sets. We analyzed band-resight and mercury data for 776 adult loons in Wisconsin and New England, USA, from 1991 to 2001 to 1) estimate annual survival rates and 2) investigate the relation between mercury exposure and survival. The model-averaged estimate of apparent survival was 0.87, whereas the approximate survival rate (accounting for movement) was 0.92. We found no differences in apparent survival by geographic location or sex and no relation between survival and mercury. Power analyses showed that we were only likely to detect differences in survival ≥3%. Small differences in survival (<3%), which may be important to loon population viability, were unlikely to be detected in our dataset. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):665–673; 2008)  相似文献   

17.
Responses of breeding common loons to human activity in upper Michigan   总被引:1,自引:1,他引:0  
Caron  James A.  Robinson  William L. 《Hydrobiologia》1994,279(1):431-438
Breeding populations of the common loon (Gavia immer) in Michigan have declined in the past several decades, resulting in classification of this species as threatened under state law. Factors responsible for the decline are unknown, but may include toxic contaminants, mortality in commercial fish nets, and human disturbance of breeding sites. To assess the latter possibility, 960 hours of observation were devoted to observing human-loon interactions on two sets of lakes, one with restricted human use (minimal or no shoreline development and open to canoe use only), and another with unrestricted use (varying amounts of shoreline development and motorboat traffic). Six mated pairs of loons on six restricted use (r-u) lakes were compared to eight loon pairs on seven open-use (o-u) lakes. The number of nests that hatched young per nest started was not significantly different between the two sets of lakes (7 of 13 (0.62) on r-u lakes vs 8 of 17 (0.47) on o-u lakes), despite significantly more human activity on o-u lakes. Chicks hatched per pair of loons were likewise not significantly different (1.1 vs 1.2 on r-u and o-u lakes, respectively). Fledging success was significantly lower on r-u lakes (7 chicks fledged of 11 hatched) than on o-u lakes (13 fledged of 13 hatched). Human activity on o-u lakes was 2–3 times that on r-u lakes during chick rearing, but time spent by adult loons tending and feeding chicks was not significantly different between the two types of lakes. The larger size of most o-u lakes may have allowed loons a greater opportunity to avoid human disturbance. Higher levels of human activity did not affect production of chicks by loons under the conditions observed, but these results should not be extrapolated to lakes experiencing much higher human use.  相似文献   

18.
The paleontological history of Nypa, known today as the mangrovepalm, is traced through geological time back to the Late Cretaceous. Emphasis is laid on the New World occurrences, especially in NorthAmerica, where Nypa is known from fossil fruits and pollen. In SouthAmerica, the stratigraphic range of this palm extends from theMaastrichtian to the late Eocene, whereas in North America, Nypa isrestricted to only the Eocene. Nypa occurs as pollen all along theAmerican Gulf Coast from the early Eocene (Ypresian) to the late Eocene(Priabonian), while fruit records come from the early and middle Eoceneof Maryland and Texas, respectively. The floristics of these Eocenemangroves, including possible mangrove associates, and the developmentof mangrove vegetation in the neotropics through the Tertiary andQuaternary, are discussed. New paleobotanical evidence from a middleEocene faunal and floral assemblage in Texas, the Casa Blanca flora (LaredoFormation, Claiborne Group), which contains fossil Nypa pollen andfruits, is described in detail.  相似文献   

19.
Two new species ofAcer fossil woods,A. momijiyamense andA. Watarianum, are described and a short review of fossil wood of this genus from the Tertiary of Japan is given. In the course of a study on three fossil wood species which have been described asAcer andAcernium from Japan, it is noticed thatAcernium iwatense Watari does not belong toAcer but toPrunus of the Rosaceae, and is therafore transferred intoPrunus asPrunus iwatense comb. nov.  相似文献   

20.
Four species of dicotyledonous woods including three new species,Aextoxicoxylon harambouri sp. nov.,Myrceugenellites maytenoides sp. nov.,Laurelites doroteaensis sp. nov. andLaurinoxylon uniseriatum Gothan, were described from the Tertiary of Cerro Dorotea, Ultima Esperanza and Fuego Island, Chile. It was elucidated thatNothofagoxylon boureaui Salard from Cerro Dorotea is synonymous withLaurinoxylon uniseriatum from Antarctica. Consecutive number from the previous paper (Nishida, 1984). Contributions from the Laboratory of Phylogenetic Botany, Chiba University No. 118 and contributions from Chiba University Botanical Expedition to the Andes No. 17. Supported by a Grant in-Aid for Overseas Scientific Survey from the Ministry of Education, Science and Culture Nos. 7405, 404114 and 62043014.  相似文献   

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