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1.
Károly Schöll 《Biologia》2009,64(5):951-958
Gemenc floodplain lies between river kilometres km 1503 and 1469 of the Danube River; it is a part of the Danube-Dráva National Park in Hungary. The floodplain is one of the largest in Europe with an 18,000 hectares (Natura 2000) area, and various characteristic side arms and backwaters which lie completely in the floodplain. The area needs hydrological revitalization because of the sinking of the river bed caused by the regulation of the main arm at the end of the 19th century. For this revitalization an exhaustive knowledge of the hydrobiological relationships among the different water bodies is required. The aims of this study were to explore connections among the hydrological events, physico-chemical parameters of the water bodies and the diversity of the planktonic rotifer assemblages. From 2002 to 2004, 56 planktonic and 15 tychoplanktonic rotifer taxa were found in the area. The diversity of rotifer assemblages was generally higher in the parapotamal water bodies than in the main arm and in the plesio/paleo-potamal water bodies, which could be explained by the intermediate disturbance hypothesis. The diversity, dominance, and evenness of the assemblages were correlated with water flow and water temperature. The most important factors influencing the diversity patterns were the occurrence of flow (retention time) as a disturbance, connectivity with the main arm, and habitat diversity of the given water body. Most of these factors are determined by the water level fluctuation of the main arm.  相似文献   

2.
Plant species diversity is surveyed in the southern part of the Taï National Park (TNP), Côte d’Ivoire. This park is the largest remaining tract of pristine forest in the West African rainforest biodiversity hotspot. Plant assemblages and environment factors were surveyed in 39 temporary 625-m2 plots within three areas. The species list was completed thanks to itinerant prospections. TWINSPAN classification and detrended correspondence analysis were applied to the 39 relevés. We recorded a total of 916 plant species, including 169 West African endemics, that rises the floristic richness of TNP in 1233 species. Most plant species recorded were Guineo-Congolian species (90.9%) among which 8% were ‘Sassandrian species’, i.e. endemics of the extreme southwest Côte d’Ivoire. Eight of these endemics were exclusive of the southern part of TNP. The forest is very species-rich, particularly in Rubiaceae, Leguminosae and Euphorbiaceae. Most of the sampled species (59.5%) were erect phanerophytes with a dbh≤10 cm. We distinguished 7 plant community types, mainly determined by geomorphology and disturbance history. Lowland forests were typical dense evergreen forests with different degrees of maturity related to historical human impact. Inselbergs and swampy depressions provide an original azonal vegetation. We conclude that the southern part of TNP contributes significantly to the regional biodiversity hotspot since it includes the last remnants of primary evergreen rainforest and contains species assemblages from both higher rainfall biomes on moist soils derived from schist parent material and lower rainfall biomes on inselberg slopes and top. As anthropogenic disturbance clearly reduces biodiversity, these last remnants should be integrally protected.  相似文献   

3.

Background

Management and conservation of biodiversity requires adequate species inventories. The Yasuní National Park is one of the most diverse regions on Earth and recent studies of terrestrial vertebrates, based on genetic evidence, have shown high levels of cryptic and undescribed diversity. Few genetic studies have been carried out in freshwater fishes from western Amazonia. Thus, in contrast with terrestrial vertebrates, their content of cryptic diversity remains unknown. In this study, we carried out genetic and morphological analyses on characin fishes at Yasuní National Park, in eastern Ecuador. Our goal was to identify cryptic diversity among one of the most speciose fish families in the Amazon region. This is the first time that genetic evidence has been used to assess the species content of the Napo Basin, one of the richest regions in vertebrate diversity.

Results

Phylogenetic analyses of partial mitochondrial 16S ribosomal RNA gene (∼600 pb) DNA sequences from 232 specimens of the family Characidae and its closest groups revealed eight candidate new species among 33 species sampled, representing a 24% increase in species number. Analyses of external morphology allowed us to confirm the species status of six of the candidate species.

Conclusions

Our results show high levels of cryptic diversity in Amazonian characins. If this group is representative of other Amazonian fish, our results would imply that the species richness of the Amazonian ichthyofauna is highly underestimated. Molecular methods are a necessary tool to obtain more realistic inventories of Neotropical freshwater fishes.  相似文献   

4.
“Brush structures” are temporary wooden structures built with unmodified local materials and used as shelters by First Nation Peoples in the forests of the Yukon prior to European contact. This paper reports a preliminary attempt to date these structures using dendrochronology. Investigations were carried out of four njel (“teepee like”) structures and eight män-ku (low 2–3 sided wall structures) at four main sites. The primary material cored was poles (dead spruce trunks), often only 10–20 cm diameter, with narrow, sometimes extremely suppressed ring sequences. These structures are dated between 1865 and 1887, based on the latest (outermost) ring in the sampled material. The limited sampling and use of old wood in these structures (whether fire-kill, standing dead or reused from previous features) makes it difficult to give precise dates for the initial evidence of First Nation activity at these sites: more extensive sampling could provide further insight into the settlement history and construction techniques used. The sites investigated date from the latter half of the nineteenth century shortly before the first European gold rush to this region.  相似文献   

5.
The impacts of mowing and of flooding on the leafhopper communities of a river flood plain were investigated. Samples were taken by a motor-driven suction apparatus. In 2001 leafhoppers were collected in a variety of sites differing in land use (fallows, mown sites) and in flood intensity (high, medium, low, none). In 2002 samples were only taken in fallows subject to different flooding regimes.In fallows, more species (43) were collected than in mown sites (33). Flooding had an effect only in fallows. Here, the most species-rich (29) communities occurred in sites not subject to flooding, whereas fewest species (21) were found in sites subject to regularly occurring long lasting winter floods. Mown sites were dominated by pioneer species. In fallows, the communities differed in respect to flood intensity. In fallows that were subject to summer and winter floods pioneer species prevailed. In contrast, in fallows that were flooded a long time during winter but not in summer, communities of very specialised species were found which were not very species-rich.For the conservation of the typical leafhopper communities of floodplain grassland, management by mowing should be at least reduced if not totally stopped and natural flooding dynamics should be restored.  相似文献   

6.
A list of 243 Microlepidoptera species found in the territory of the Curonian Spit (both in its Russian and Lithuanian parts), in addition to that in the first part of the present publication (Sinev and Shapoval, 2013), is given: Gelechiidae (33), Tortricidae (138), and Crambidae (72 species). 142 species have been collected in the territory of the “Kurshskaya Kosa” National Park, including 49 species new to the Curonian Spit, 30 species new to Kaliningrad Province and 3 species (Scrobipalpa obsoletella, Scrobipalpa pauperella, and Catoptria osthelderi) new to the fauna of Russia.  相似文献   

7.
Simian retroviruses are precursors of all human retroviral pathogens. However, little is known about the prevalence and coinfection rates or the genetic diversity of major retroviruses—simian immunodeficiency virus (SIV), simian T-cell lymphotropic virus type 1 (STLV-1), and simian foamy virus (SFV)—in wild populations of nonhuman primates. Such information would contribute to the understanding of the natural history of retroviruses in various host species. Here, we estimate these parameters for wild West African red colobus monkeys (Piliocolobus badius badius) in the Taï National Park, Côte d''Ivoire. We collected samples from a total of 54 red colobus monkeys; samples consisted of blood and/or internal organs from 22 monkeys and additionally muscle and other tissue samples from another 32 monkeys. PCR analyses revealed a high prevalence of SIV, STLV-1, and SFV in this population, with rates of 82%, 50%, and 86%, respectively. Forty-five percent of the monkeys were coinfected with all three viruses while another 32% were coinfected with SIV in combination with either STLV or SFV. As expected, phylogenetic analyses showed a host-specific pattern for SIV and SFV strains. In contrast, STLV-1 strains appeared to be distributed in genetically distinct and distant clades, which are unique to the Taï forest and include strains previously described from wild chimpanzees in the same area. The high prevalence of all three retroviral infections in P. b. badius represents a source of infection to chimpanzees and possibly to humans, who hunt them.Lentiviruses and deltaretroviruses that infect African nonhuman primates have received considerable attention as they are the precursors of all pathogenic human retroviruses: human immunodeficiency virus types 1 and 2 (HIV-1/HIV-2) and human T-cell lymphotropic virus type 1 (HTLV-1). These human infections are the results of past zoonotic transfers of simian immunodeficiency virus (SIV) and simian T-cell lymphotropic viruses type 1 (STLV-1) from wild monkeys and apes into local human populations, presumably through primate hunting and handling of primate bushmeat (13, 19, 43, 46, 55, 58, 59). Via the same route, zoonotic transmission of simian foamy virus (SFV), a spumaretrovirus whose exact pathogenicity in human hosts is still unknown, has also been shown (64). The increasing contact between humans and wild primates implies that further zoonotic transmission of retroviruses is likely to happen (42, 63). Studying the occurrence and circulation of simian retroviruses such as SIV, STLV-1, and SFV in wild primate populations enables us to better understand retrovirus evolution in primates and also provides tools for monitoring possible future retroviral zoonotic events.Systematic studies of SIV, STLV-1, and SFV in wild primates are relatively rare. Many use bushmeat samples, which can vary in their quality and are prone to cross-contamination from butchering and storage with other carcasses. Confiscated primates are also not representative of the situation in the wild since the animals are caught at a young age when the occurrence of different retroviruses may be extremely low (24). The technical possibilities for the detection of various pathogens in noninvasive samples such as urine and feces have greatly improved and are frequently used; however, in general, the sensitivity of detection methods is higher when blood and tissue samples are used (25, 32, 47). Such samples can be collected if fresh carcasses are found, or they can be collected by anesthetizing live primates for sampling purpose, animal translocation, or medical intervention, such as snare removal. The practical and ethical issues of each of the sampling methods have been discussed elsewhere (12, 14).Red colobus monkeys [Procolobus (Piliocolobus)] are interesting subjects for retroviral infection studies for a number of reasons. First, they are widely distributed (yet in a fragmented manner) from East to West Africa, which suggests that red colobus species and subspecies, or more likely ancestor(s) of these, could have been key hosts in transmitting retroviruses across tropical Africa (4, 54). Second, as they are herbivore primates, the hunting of other primates can be excluded as a route of infection. Finally, these monkeys are frequently hunted by humans and chimpanzees and represent a possibly large reservoir for retroviruses and other pathogens that ought to be investigated further (2, 45).Very little information is available about the prevalence and coinfection of SIV, STLV-1, and SFV in wild red colobus monkeys across Africa. In other colobine monkeys only SIV has been documented: in olive colobus (Procolobus verus) in Côte d''Ivoire and in black and white colobus (Colobus guereza) in Cameroon (7, 8). Based on fecal samples from habituated adult individuals, the prevalence of SIV in West African red colobus monkeys (SIVwrc; local subspecies, Piliocolobus badius badius) has been estimated to a minimum of 26% in the Taï National Park, Côte d''Ivoire, but the authors recognized the low sensitivity of viral RNA detection in fecal samples (34). Another study conducted on the same population revealed that 5 out of 10 blood samples were SIV positive (7). These results highlight that the most reliable prevalence data are based on analyses of blood/tissue samples although such sampling is not always feasible for reasons discussed above. Published prevalence information concerning STLV-1 and SFV in wild red colobus monkeys (STLV-1wrc and SFVwrc) in the same area is restricted to results obtained from analyses of a limited number of blood and necropsy samples collected as a part of studies whose focus was on cross-species transmission of these two viruses to chimpanzees (27, 28). However, these samples indicated a high prevalence of STLV-1wrc and SFVwrc in the red colobus monkey population (56% and 90%, respectively). A recent study from Uganda, East Africa, estimated the prevalence of SIV, STLV-1, and SFV in another red colobus species (Piliocolobus rufomitratus tephrosceles) to be 22.6%, 6.4%, and 97%, respectively (15). The study was performed using blood samples collected from anesthetized wild red colobus monkeys living in their natural habitat, which allowed reliable assessment of the prevalence and genetic diversity of these three retroviruses.The preliminary data from the Taï National Park indicate that there might be great variation in the prevalence of retroviruses across the African continent, even in closely related species of wild primates. Here, we aimed at generating reliable prevalence and coinfection data for SIVwrc, STLV-1wrc, and SFVwrc based on the analysis of blood and tissue samples from wild Western red colobus monkeys. We expected that this would allow for proper comparison of retroviral prevalence in the allied species P. b. badius and P. r. tephrosceles.  相似文献   

8.
Stampflii's putty-nosed monkeys Cercopithecus nictitans stampflii are large, rare, poorly known guenons with a discontinuous distribution in West Africa. Putty-nosed monkeys occur at low densities in Ivory Coast's Tai National Park where they are believed to have migrated from less forested regions north of the park (Eckardt and Zuberbühler: Behav Ecol 15 (2004) 400-411). In this article, we compare the positional behavior of Putty-nosed monkeys to that of three other guenon species in the Tai Forest and provide an additional test of the relationship among locomotion, body size, maintenance activity, and habitat use in generalized arboreal quadrupeds. Our results indicate that putty-nosed monkeys confine the great majority of their locomotion to the main canopy where most movement occurs on boughs and branches. Comparison of overall locomotor frequencies across the four Tai guenon species reveals a general pattern; quadrupedalism accounts for at least 70% of the total profile, climbing ranges between 15 and 20%, and leaping accounts for 5-10% of total movement. The overall locomotor consistency among the taxa, especially between putty-nosed and Diana monkeys, is significant considering marked interspecific differences in support preference and strata use.  相似文献   

9.
Abstract. An entomological inventory was conducted between 1993 and 1996 to obtain information on the diversity of mosquitoes (Diptera: Culicidae) in the Jaú National Park, State of Amazonas, Brazil. A total of 10,159 adult (91%) and immature mosquito specimens, representing 130 taxa (species + morphospecies) in 16 genera, was collected. A species list for the family Culicidae is presented, including 30 new records for the State of Amazonas. The collecting localities were restricted to the alluvial subregion of the Open Tropical Forest found in the park. Most of the specimens (71%) were collected in forest habitats and the rest in areas of second growth and peridomicile. The majority of immature specimens (46%) were collected in bodies of water along the edges of rivers, flooded forests, lakes and streams. Among the various collection methods used, the Centre for Disease Control (CDC) and Shannon traps together were responsible for capturing 60% of the adults. More than 90% of the material collected belongs to the genera Culex (65%), Psorophora (19%), Wyeomyia (4%), and Anopheles (3%), which together represent 70% of the identified taxa. The genus Culex presented the largest number of species (45). The species Culex (Melanoconion) vaxus, Cx. (Mel.) pedroi, Psorophora amazonica, Cx. (Mel.) portesi and Cx. (Mel.) theobaldi together (< 4% of the recorded species) represent more than 63% of the material collected and identified to the species level. The most abundant species was Cx. (Mel.) vaxus, representing 17% of the material identified to species. The possible epidemiological and ecological implications of the species hereby recorded in the Jaú National Park are presented and discussed.  相似文献   

10.
The candidate order “Pelagibacterales” (SAR11) is one of the most abundant bacterial orders in ocean surface waters and, periodically, in freshwater lakes. The presence of several stable phylogenetic lineages comprising “Pelagibacterales” correlates with the physico-chemical parameters in aquatic environments. A previous amplicon sequencing study covering the bacterial community in the salinity gradient of the Baltic Sea suggested that pelagibacteral subclade SAR11-I was replaced by SAR11-IIIa in the mesohaline region of the Baltic Sea. In this current study, we investigated the cellular abundances of “Pelagibacterales” subclades along the Baltic Sea salinity gradient using catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH). The results obtained with a newly designed probe, which exclusively detected SAR11-IIIa, were compared to CARD-FISH abundances of the marine SAR11-I/II subclade and the freshwater lineage SAR11-IIIb (LD12). The results showed that SAR11-IIIa was abundant in oligohaline–mesohaline conditions (salinities 2.7–13.3), with maximal abundances at a salinity of 7 (up to 35% of total Bacteria, quantified with a universal bacterial probe EUB). As expected, SAR11-I/II was abundant (27% of EUB) in the marine parts of the Baltic Sea, whereas counts of the freshwater lineage SAR11-IIIb were below the detection limit at all stations. The shift from SAR11-IIIa to SAR11-I/II was confirmed in the vertical salinity gradient in the deeper basins of the Baltic Sea. These findings were consistent with an overlapping but defined distribution of SAR11-I/II and SAR11-IIIa in the salinity gradient of the Baltic Sea and suggested the adaptation of SAR11-IIIa for growth and survival in mesohaline conditions.  相似文献   

11.
Amphibian chytridiomycosis, caused by infection with the non-hyphal, zoosporic chytrid fungus Batrachochytrium dendrobatidis (Bd), is an emerging infectious disease recognised as a cause of recent amphibian population declines and extinctions worldwide. The Do?ana National Park (DNP) is located in southwestern Spain, a country with widespread Bd infection. This protected area has a great diversity of aquatic habitats that constitute important breeding habitats for 11 native amphibian species. We sampled 625 amphibians in December 2007 and February to March 2008, months that correspond to the early and intermediate breeding seasons for amphibians, respectively. We found 7 of 9 sampled species to be infected with Bd and found differences in prevalence between sampling periods. Although some amphibians tested had higher intensities of infection than others, all animals sampled were apparently healthy and, so far, there has been no evidence of either unusually high rates of mortality or amphibian population declines in the DNP.  相似文献   

12.
Jaú National Park is a large rain forest reserve that contains small populations of four caiman species. We sampled crocodilian populations during 30 surveys over a period of four years in five study areas. We found the mean abundance of caiman species to be very low (1.0 +/- 0.5 caiman/km of shoreline), independent of habitat type (river, stream or lake) and season. While abundance was almost equal, the species' composition varied in different waterbody and study areas. We analysed the structure similarity of this assemblage. Lake and river habitats were the most similar habitats, and inhabited by at least two species, mainly Caiman crocodilus and Melanosuchus niger. However, those species can also inhabit streams. Streams were the most dissimilar habitats studied and also had two other species: Paleosuchus trigonatus and P. palpebrosus. The structure of these assemblage does not suggest a pattern of species associated and separated by habitat. Trends in species relationships had a negative correlation with species of similar size, C. crocodilus and P. trigonatus, and an apparent complete exclusion of M. niger and P. trigonatus. Microhabitat analysis suggests a slender habitat partitioning. P. trigonatus was absent from river and lake Igapó (flooded forest), but frequent in stream Igapó. This species was the most terrestrial and found in microhabitats similar to C. crocodilus (shallow waters, slow current). Melanosuchus niger inhabits deep, fast moving waters in different study areas. Despite inhabiting the same waterbodies in many surveys, M. niger and C. crocodilus did not share the same microhabitats. Paleosuchus palpebrosus was observed only in running waters and never in stagnant lake habitats. Cluster analysis revealed three survey groups: two constitute a mosaic in floodplains, (a) a cluster with both M. niger and C. crocodilus, and another (b) with only C. crocodilus. A third cluster (c) included more species, and the presence of Paleosuchus species. There was no significant difference among wariness of caimans between disturbed and undisturbed localities. However, there was a clear trend to increase wariness during the course of consecutive surveys at four localities, suggesting that we, more than local inhabitants, had disturbed caimans. The factors that are limiting caiman populations can be independent of human exploitation. Currently in Amazonia, increased the pressure of hunting, habitat loss and habitat alteration, and there is no evidence of widespread recovery of caiman populations. In large reserves as Jaú without many disturbance, most caiman populations can be low density, suggesting that in blackwater environments their recovery from exploitation should be very slow.  相似文献   

13.
The zooplankton of 18 temporary ponds in the Doñana National Park (SW Spain) was studied during floods in February and May 1997. A total of 37 rotifer taxa and 34 crustaceans species were identified (17 cladocerans, 2 ostracans, 4 diaptomids, 7 cyclopodids, 1 harpacticoid, 1 anostracan, 1 notostracan and 1 conchostracan). Zooplankton samples were collected separately from the littoral and the open-water of 12 different ponds. Commonly distributed zooplankton species (frequency of appearance 50%) were not segregated to either the littoral or the open-water according to a chi-square test (P>0.005). The study ponds were divided into seasonal, intermediate and ephemeral ponds according to the length of their hydroperiod. The total numbers of both crustacean and rotifer taxa were highest in the intermediate-hydroperiod ponds (26 and 32 taxa, respectively). The total number of zooplankton taxa collected in both February and May was not significantly correlated to the hydroperiod of the temporary ponds of Doñana during the study period (r=0.165, P=0.526). 21 rotifer taxa and 20 crustacean species were found in the ephemeral ponds; the number of restricted species was also relatively high (3 rotifers and 4 crustaceans). Therefore, the ephemeral ponds held a relatively rich community during floods compared to other temporary ponds of Doñana despite their small size and short wet phase.  相似文献   

14.
The epidemiology of Ancylostoma spp. was studied in the endangered Iberian lynx (Lynx pardinus) in the Do?ana National Park, south-west Spain. Faecal samples were collected throughout a complete annual cycle (August 1997 to September 1998). The overall egg prevalence of Ancylostoma spp. was 57.8%. The pattern of abundance of Ancylostoma spp. eggs in faeces was overdispersed. Juvenile lynx demonstrated a statistically higher prevalence and abundance of Ancylostoma spp. than in adults. These levels of egg output (maximum 21195 epg), as previously reported in free ranging large felid cubs, could be close to disease involvement. The potential pathogenicity of hookworms and the influence of individual and ecological factors on hookworm transmission in the Iberian lynx from the Do?ana National Park population are discussed.  相似文献   

15.
Members of the genus Colobus have been observed to associate frequently with Cercopithecus monkeys in several African sites. In the Taï National Park, Ivory Coast, one group of western red colobus was found to be in association with one particular group of diana monkeys more than could be expected by chance (Holenweg et al., 1996). We show that dyadic association is not an idiosyncrasy of these two groups, but rather a pattern that is general for our study site. All five red colobus groups we studied were closely associated with diana monkeys during more than 60% of the time. Four groups had one particular diana partner group, the fifth two different partners. Apart from the red colobus, three more primate species, the olive colobus, Campbell's monkey, and the lesser spot-nosed monkey, were also strongly attracted to diana monkeys.  相似文献   

16.
A list of 212 Microlepidoptera species found in the territory of the Curonian Spit (both in its Russian and Lithuanian parts) is given: Micropterigidae (1), Eriocraniidae (1), Nepticulidae (16), Opostegidae (1), Heliozelidae (1), Adelidae (3), Prodoxidae (2), Incurvariidae (2), Tineidae (8), Psychidae (1), Douglasiidae (2), Bucculatricidae (3), Gracillariidae (26), Yponomeutidae (12), Plutellidae (3), Acrolepiidae (2), Glyphipterigidae (3), Lyonetiidae (1), Ethmiidae (1), Depressariidae (12), Elachistidae (20), Chimabachidae (1), Oecophoridae (9), Stathmopodidae (1), Batrachedridae (2), Coleophoridae (25), Momphidae (3), Blastobasidae (2), Cosmopterigidae (3), Choreutidae (1), Schreckensteiniidae (1), Epermeniidae (1), Alucitidae (1), Pterophoridae (7) and Pyralidae (35 species). 113 species of 24 families have been collected in the territory of the “Kurshskaya Kosa” National Park, including 45 species new to the Curonian Spit and 32 species new to Kaliningrad Province.  相似文献   

17.
18.
The transition zone between forest and savanna is typically characterized by a dynamic patchwork of forest and savanna. We studied the woody plant species composition of 49 forest islands, 18 savanna, and 3 gallery forest plots in the Comoé National Park (Ivory Coast), West Africa's largest savanna reserve. TWINSPAN makes a clear distinction in vegetational composition between these three major habitat types but, nevertheless, more than 50% of the 292 species occur in at least 2 of them. The gallery forest is dominated by Cynometra megalophylla (Caesalpiniaceae), a genus known to dominate humid forests in other afrotropical regions. Ordination reveals four distinct categories of forest islands, (1) humid forests comparable to the gallery forest in their species composition, (2) dry disturbed and (3) dry undisturbed forests and (4) forests formerly inhabited by humans. Disturbed forests harbor more savanna species but also a distinct group of disturbance-tolerant forest species. Compared to other forest species, in this latter group we found an exceptionally high fraction of animal dispersed species (80% vs. 58%), while wind dispersed species or species lacking long distance seed dispersal mechanisms were correspondingly rare. This pattern occurs in spite of the fact that the frequency of wind dispersed species in general increases from dense humid forests to open dry forests and savanna. Species lacking long distance dispersal mechanisms are most abundant among those specialized on humid forests. These observations suggest that the species composition of forest islands is to some extent determined by the seed dispersal abilities of the different species.  相似文献   

19.
A comparative field study of the locomotion of woolly monkeys (Lagothrix lagothricha) and spider monkeys (Ateles belzebuth) in undisturbed rainforest of northeastern Ecuador reveals substantial differences in their use of suspensory modes. Ateles performed both more brachiation (by forelimbs and tail, with trunk rotation), and forelimb swing (similar to brachiation, but without trunk rotation) than Lagothrix. In contrast, in Lagothrix 20% of suspensory movement was by pronograde forelimb swing, which resembles forelimb swing except that the body is held in a pronograde orientation due to the tail and/or feet intermittently grasping behind the trailing forelimb. Ateles never exhibited this mode. Both brachiation and forelimb swing by Ateles were more dynamic than in Lagothrix, consisting of higher proportions of full-stride bouts (versus single-step). Both species used smaller supports for suspensory than for quadrupedal locomotion, and Ateles used both smaller and larger supports for suspension than did Lagothrix. Analysis of support inclination shows that both species tended to perform more above-support movement on horizontal supports and more below-support (suspensory) movement from oblique supports. Our attempt to elucidate the aspects of canopy structure that favor suspension suggests the need for additional kinds of observational data, focusing on the "immediate structural context" of positional events.  相似文献   

20.
Recently a discussion is taking place about the Scontrone (l’Aquila) and Gargano (Apulia, Italy) mammal faunas and the age of their immigration. Mazza and Rustioni (2008) dated the Scontrone mammal fossils as Tortonian on the basis of their position in the Lithothamnium Limestone and came to the conclusion that some elements of the Scontrone and Gargano faunas must have colonised the area in Oligocene or Early Miocene times. Van den Hoek Ostende et al. (2009) disagreed with this interpretation and suggested a Late Miocene (10 Ma) age for the time of immigration. We think the arguments to place Scontrone in the Tortonian are not convincing. An analysis of the potential ancestors of each of the Gargano faunal components shows that a Messinian age for the immigration is fully compatible with the distribution of these ancestors in the European Miocene.  相似文献   

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