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1.
The positional behavior and habitat use of a group of white uakaries (Cacajao calvus calvus) was observed for 6 weeks in the dry season at Lake Teiú, Brazil. Data are presented for feeding, traveling, and resting activities. The most common feeding posture is sit, followed by stand. Cacajao frequently exhibits locomotor behaviors while in feeding trees, using pronograde clamber and quadrupedal walk. The most frequently used locomotor behaviors in travel are quadrupedal walk, leap, and pronograde clamber. Quadrupedal run and drop also figure importantly in the behavioral repertoire. The most frequent resting posture was sit, followed by ventral lie. Compared to representative members of the other pitheciin genera, Pithecia and Chiropotes, Cacajao engages in more locomotion while feeding, and uses more pedal suspension. While traveling, pronograde clamber and drop are more frequently used by Cacajao. Multiple, deformable supports are used more by Cacajao than by the other pitheciins throughout all activities. Overall, the positional behavior of Cacajao is more similar to that of Chiropotes than of Pithecia. Cacajao's behavioral solutions to the problems of balance imposed by its greatly reduced tail are discussed. © 1996 Wiley-Liss, Inc.  相似文献   

2.
One hundred and forty-three sakis (Pithecia), 107 bearded sakis (Chiropotes), and 7 red uakaris (Cacajao) were studied in relation to 18 genetic loci expressed on blood through electrophoretic techniques. Eight of the 18 loci showed intrapopulational variation. The low level of genetic diversity found inPithecia could be a consequence of a decrease in populational size due to intense habitat destruction. The genetic distances between the species investigated were:Pithecia ×Chiropotes: 0.49;Pithecia ×Cacajao: 0.57;Cacajao ×Chiropotes: 0.18–0.20. These results suggest, in accordance with other data, thatChiropotes andCacajao constitute a sister group within the pithecines.  相似文献   

3.
Pitheciines (Pithecia, Chiropotes, and Cacajao) are a specialized clade of Neotropical seed predators that exhibit postcanine teeth with low and rounded cusps and highly crenulated occlusal surface enamel. Data on feeding ecology show that Pithecia consumes proportionally more leaves than other pitheciine species, and comparative studies demonstrate its greater molar relief and relative shearing potential. However, data on pitheciine food mechanics show that Pithecia masticates seeds with greater crushing resistance than those preferred by Chiropotes. This variation predicts an opposing morphology characterized by low and more rounded occlusal surfaces in Pithecia. We build on previous research using new methods for molar surface shape quantification by examining pitheciine second molar shearing crest length, occlusal relief, surface complexity, and surface curvature relative to nonseed specializing platyrrhines and within the context of the observed interspecific variation in pitheciine feeding ecology. Consistent with the previous analyses, our findings demonstrate that pitheciine molars exhibit low shearing, relief, and curvature compared with nonseed predators, independent of phylogeny. Pitheciines also exhibit highly “complex” occlusal topography that promotes the efficient breakdown of tough seed tissues. Overall, Pithecia, Chiropotes, and Cacajao share a similar topographic pattern, suggesting adaptation to foods with similar structural and/or mechanical properties. However, Cacajao differs in surface complexity, which reflects some variation in its feeding ecology. Contrary to the predictions, Pithecia and Chiropotes do not differ in any of the topographic variables examined. The range of demands imposed on the postcanine teeth of Pithecia might therefore select for an average topography, one that converges on that of Chiropotes. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

4.

Background  

The New World monkey (Platyrrhini) subfamily Pitheciinae is represented by the genera Pithecia, Chiropotes and Cacajao. In this work we studied the karyotypes of Pithecia irrorata (2n = 48) and Cacajao calvus rubicundus (2n = 45 in males and 2n = 46 in females) by G- and C-banding, NOR staining and chromosome painting using human and Saguinus oedipus whole chromosome probes. The karyotypes of both species were compared with each other and with Chiropotes utahicki (2n = 54) from the literature.  相似文献   

5.
Pithecia pithecia andChiropotes satanas are seed predators that eat fruits with hard pericarps. We measured resistance to puncturing and crushing of fruit and seeds eaten by these two pitheciins at two localities: in evergreen rain forest at Raleighvallen-Voltzberg, Surinam, and in tropical dry/transitional moist forest on islands in Guri Lake, Venezuela. Average measurements of pericarp hardness were similar at both sites for fruit eaten byChiropotes, but a higher maximum value was obtained at the rainforest site.Chiropotes andPithecia both ate fruits that had harder pericarps than did fruits eaten byAteles paniscus, but crushing resistances of seeds eaten were lower than values forAteles. Thus, both pitheciins selected fruits with hard pericarps and soft seeds, although there were notable intergeneric differences in hardness of fruit ingested. When fruit became scarce,Pithecia ate more flowers, whileChiropotes continued to eat fruits with hard seed coverings. Chemical analysis of species of seeds eaten byPithecia suggests that they avoided seeds with extremely high tannin levels, though they tolerated moderate tannin levels in combination with high levels of lipids. We propose that sclerocarpic harvesting (the preparation and ingestion of fruit with a hard pericarp) allows pitheciin monkeys to obtain nutritious seeds, with reduced tannins, that are softer than those ingested by other frugivores.Presented at XIIIth Congress, International Primatological Society, July 27, 1990.  相似文献   

6.
Despite considerable post-cranial and cranial morphological overlap with Proconsul, Afropithecus turkanensis is distinguished from that taxon by a suite of anterior dental and gnathic characters shared in common with extant pitheciin monkeys (i.e. low crowned, robust and laterally splayed canines, procumbent incisors, prognathic premaxilla, powerful temporalis muscles, reduced or absent maxillary sinuses, and deep mandibular corpora). Pitheciins are unique among living anthropoids because their canines serve a habitual dietary function and are not strictly influenced by inter-male competition. Given the functional association between pitheciin canine morphological specializations and sclerocarp foraging, a feeding strategy where the hard pericarps of unripe fruit are mechanically deformed by the canines, it has been suggested that Afropithecus may also have used its canines in a dietary context. This is confirmed by quantitative morphometric analyses of Afropithecus canine curvature and basal dimensions demonstrating that Afropithecus and extant pitheciins (Chiropotes, Cacajao) are distinguished from all other anthropoids by pronounced and evenly distributed mesial canine crown contours as well as greater resistance to canine bending in both the mesiodistal and labiolingual axes. In addition, Afropithecus, Chiropotes and Cacajao are also shown to have significantly longer and more curved premaxillae with greater incisor procumbency that effectively isolates the incisor and canine functional complexes. These morphological similarities are a result of convergence and not a shared derived ancestry. Despite their considerable morphological overlap, it is unlikely that Afropithecus and extant pitheciin diets are identical given significant dissimilarities in their post-canine morphology, maximum angular gape and body size. Nevertheless, Afropithecus canine dietary function is unique among hominoids and may have been a key component for the expansion of hominoids into Eurasia at the end of the early Miocene.  相似文献   

7.
8.
A discriminant analysis was performed on 226 ceboid skulls using data on emissary foramina size and shape. The purposes of the study are to 1) measure the success with which these discriminating variables can distinguish among platyrrhine genera and 2) derive a set of classification functions which will permit the classification of new cases with unknown group membership (i.e., fossil skulls). This technique is able to correctly classify 80% of the 226 ceboid skulls. Support is given to the allocation of Chiropotes, Cacajao, and Pithecia into one morphologically unified subfamily, Pitheciinae. Alouatta, Ateles, and Lagothrix also share many similarities in emissary foramina size and shape and their inclusion into one subfamily, Atelinae, is probably warranted. The distinctiveness of Cebus in these same morphological features is apparent. Possibilities for extending this procedure to study fossil lineages in platyrrhines are discussed.  相似文献   

9.
Nuclear sequences of the 1.8 kilobase (kb) long intron 1 of the interstitial retinol-binding protein gene (IRBP), previously determined for 11 of the 16 extant genera of New World monkeys (superfamily Ceboidea, infraorder Platyrrhini), have now been determined for the remaining 5 genera. The maximum parsimony trees found, first with IRBP sequences alone and then with tandemly combined IRBP and ϵ-globin gene sequences from the same species, supported a provisional cladistic classification with the following clusters. Subtribes Callitrichina (Callithrix, Cebuella), Callimiconina (Callimico), Leontopithecina (Leontopithecus) and Saguina (Saguinus) constitute subfamily Callitrichinae, and subfamilies Callitrichinae, Aotinae (Aotus), and Cebinae (Cebus, Saimiri) constitute family Cebidae. Subtribes Chiropotina (Chiropotes, Cacajao) and Pitheciina (Pithecia) constitute tribe Pitheciini; and tribes Pitheciini and Callicebini (Callicebus) constitute subfamily Pitheciinae. Subtribes Brachytelina (Brachyteles, Lagothrix) and Atelina (Ateles) constitute tribe Atelini, and tribes Atelini and Alouattini (Alouatta) constitute subfamily Atelinae. The parsimony results were equivocal as to whether Pitheciinae should be grouped with Atelinae in family Atelidae or have its own family Pitheciidae. The cladistic groupings of extant ceboids were also examined by different stochastic evolutionary models that employed the same stochastic process of nucleotide substitutions but alternative putative phylogenetic trees on which the nucleotide substitutions occurred. Each model, i.e., each different tree, predicted a different multinomial distribution of nucleotide character patterns for the contemporary sequences. The predicted distributions that were closest to the actual observed distributions identified the best fitting trees. The cladistic relationships depicted in these best fitting trees agreed in almost all cases with those depicted in the maximum parsimony trees. © 1996 Wiley-Liss, Inc.  相似文献   

10.
Best known for aquatic colonial algae such as Hydrodictyon, Pediastrum, or Scenedesmus, the order Sphaeropleales also contains numerous coccoid taxa from aquatic and terrestrial habitats. Recent findings indicate that coccoid lineages in this order are very diverse genetically and may be the prevalent form, although their diversity is often hidden morphologically. This study characterizes coccoid algae recently discovered from desert soil crusts that share morphological and ecological features with the genera Bracteacoccus, Pseudomuriella, and Chromochloris. Analyses of a multi‐gene data set that includes members from all sphaeroplealean families are used to examine the monophyly of these morphologically similar taxa, which are shown instead to be phylogenetically distinct and very divergent. We propose new generic names for these lineages: Bracteamorpha, Rotundella, and Tumidella. In addition, we propose an updated family‐level taxonomy within Sphaeropleales that includes ten new families of coccoid algae to accommodate the newly presented genera and many incertae sedis taxa in the order: Bracteamorphaceae, Chromochloridaceae, Dictyococcaceae, Dictyochloridaceae, Mychonastaceae, Pseudomuriellaceae, Rotundellaceae, Schizochlamydaceae, Schroederiaceae, and Tumidellaceae.  相似文献   

11.
Unlike most other green algae, trebouxiophyceans are predominantly aerophytic and contain many symbiotic representatives. In recent years, a number of new terrestrial trebouxiophycean taxa were described from soils, tree bark, and lichens. The present phylogenetic study reveals three new lineages of free‐living trebouxiophyceans found in North American desert soil crusts and proposes new generic names to accommodate them: Desertella, Eremochloris, and Xerochlorella. This survey of desert isolates also led to discovery of representatives of seven existing genera of trebouxiophyceans. Two of these genera have never been reported to contain desert representatives and one was known previously only from aquatic habitats. Furthermore, we expand the known geographic range of the recently described genus Chloropyrula, heretofore only known from the Ural Mountains. We demonstrate that the diversity of trebouxiophyceans is still underestimated and poorly understood, and that most major trebouxiophycean lineages contain desert‐dwelling taxa.  相似文献   

12.
As the taxonomic knowledge of cyanobacteria from terrestrial environments increases, it remains important to analyze biodiversity in areas that have been understudied to fully understand global and endemic diversity. This study was completed as part of a larger algal biodiversity study of the soil biocrusts of San Nicholas Island, California, USA. Among the taxa isolated were several new species in three genera (Atlanticothrix, Pycnacronema, and Konicacronema) which were described from, and previously restricted to, Brazil. New taxa are described herein using a polyphasic approach to cyanobacterial taxonomy that considers morphological, molecular, ecological, and biogeographical factors. Morphological data corroborated by molecular analysis including sequencing of the 16S rRNA gene, and the associated 16S–23S ITS rRNA region was used to delineate three new species of Atlanticothrix, two species of Pycnacronema, and one species of Konicacronema. The overlap of genera from San Nicolas Island and Brazil suggests that cyanobacterial genera may be widely distributed across global hemispheres, whereas the presence of distinct lineages may indicate that this is not true at the species level. Our data suggest that based upon global wind patterns, cyanobacteria in both Northern and Southern hemispheres of the Americas may have a more recent common ancestor in Northern Africa, but this common ancestry is distant enough that speciation has occurred since transatlantic dispersal.  相似文献   

13.
Use of terrestrial arthropod prey by a stream-dwelling cyprinid fish   总被引:2,自引:0,他引:2  
Synopsis The spatio-temporal availability to, and use of terrestrial (allochthonous) prey by, a subset of the fish assemblage of a Virginia piedmont stream were investigated during spring and summer. Terrestrial invertebrates were most abundant in drift nets, but least common in fish stomachs, during April. In contrast, during August, terrestrial prey dominated the diet of the major cyprinid fish,Notropis ardens, even though terrestrial prey availability in the stream declined by an order of magnitude. Several other co-occurring fishes only rarely consumed prey of terrestrial origin. Drifting terrestrial invertebrates, were concentrated at the surface near the thalweg, compared to stream margin or substrate locations. This study suggests that morphologial and behavioral constraints of individual fish taxa, including predator avoidance responses, regulate the use of terrestrial prey within a given fish assemblage.  相似文献   

14.
The phylogenetic relationships among 12 genera of treefrogs (Family, Rhacophoridae), were investigated based on a large sequence data set, including five nuclear (brain-derived neurotrophic factor, proopiomelanocortin, recombination activating gene 1, tyrosinase, rhodopsin) and three mitochondrial (partial 12S and 16S ribosomal RNA and the complete valine t-RNA) genes. Phylogenetic analysis of the nuclear gene sequences resolved three major clades. The first group included Philautus, Pseudophilautus, Kurixalus, Gracixalus, and Theloderma moloch; Pseudophilautus and Kurixalus were sister taxa. The second group consisted of Nyctixalus and Theloderma. The third group contained Feihyla, Polypedates, Rhacophorus, and Chiromantis vittatus; Polypedates and Feihyla were sister taxa. Analyses of the nuclear and mitochondrial genes supported the following results: (1) Genus Liuixalus formed the sister group of all other rhacophorines. (2) Philautus, Theloderma, and Chiromantis were not resolved as monophyletic genera. Four groups, including Philautus ocellatus and P. hainanus, P. longchuanensis and P. gryllus, P. banaensis, and P. quyeti nested well within the genera Liuixalus, Pseudophilautus, Kurixalus, and Gracixalus, respectively. (3) Theloderma moloch and Chiromantis vittatus did not cluster with other species of Theloderma and Chiromantis, respectively. Foam nesting evolved only once, as did laying eggs in a jelly-like matrix containing some bubbles. Terrestrial direct development evolved twice in the Rhacophoridae.  相似文献   

15.
In the last decade, efforts to reconstruct suprageneric phylogeny of the Cyperaceae have intensified. We present an analysis of 262 taxa representing 93 genera in 15 tribes, sequenced for the plastid rbcL and trnL-F (intron and intergenic spacer). Cyperaceae are monophyletic and resolved into two clades, here recognised as Mapanioideae and Cyperoideae, and the overall topology is similar to results from previous studies. Within Cyperoideae, Trilepideae are sister to rest of taxa whereas Cryptangieae, Bisboeckelerieae and Sclerieae are resolved within Schoeneae. Cladium and Rhynchospora (and Pleurostachys) are resolved into clades sister to the rest of Schoeneae, lending support to the recognition of these taxa in separate tribes. However, we retain these taxa in Schoeneae pending broader sampling of the group. The phylogenetic position of 40 species in 21 genera is presented in this study for the first time, elucidating their position in Abildgaardieae (Trachystylis), Cryptangieae (Didymiandrum, Exochogyne), Cypereae (Androtrichum, Volkiella), Eleocharideae (Chillania), and Schoeneae (Calyptrocarya, Morelotia). More sampling effort (more taxa and the use of more rapidly evolving markers) is needed to resolve relationships in Fuireneae and Schoeneae.  相似文献   

16.
Terrestrial breeding is a derived condition in frogs, with multiple transitions from an aquatic ancestor. Shifts in reproductive mode often involve changes in habitat use, and these are typically associated with diversification in body plans, with repeated transitions imposing similar selective pressures. We examine the diversification of reproductive modes, male and female body sizes, and sexual size dimorphism (SSD) in the Neotropical frog genera Cycloramphus and Zachaenus, both endemic to the Atlantic rainforest of Brazil. Species in this clade either breed in rocky streams (saxicolous) or in terrestrial environments, allowing us to investigate reproductive habitat shifts. We constructed a multilocus molecular phylogeny and inferred evolutionary histories of reproductive habitats, body sizes, and SSD. The common ancestor was small, saxicolous, and had low SSD. Terrestrial breeding evolved independently three times and we found a significant association between reproductive habitat and SSD, with shifts to terrestrial breeding evolving in correlation with decreases in male body size, but not female body size. Terrestrial breeding increases the availability of breeding sites and results in concealment of amplexus, egg-laying, and parental care, therefore reducing male-male competition at all stages of reproduction. We conclude that correlated evolution of terrestrial reproduction and small males is due to release from intense male-male competition that is typical of exposed saxicolous breeding.  相似文献   

17.
Peter Zwick 《Hydrobiologia》1990,194(3):207-223
Upstream oviposition flights of several Plecoptera species of the genera Leuctra, Nemoura, Isoperla and Siphonoperla along the Breitenbach, Hesse, Germany are inferred from 1. oviposition occuring upstream from emergence areas; 2. size differences and size-shifts between emerging and egg-laying females; 3. concentration of oviposition in upstream sections of the emergence area. The last point relies on direct catches of egg-laying females with sticky traps, and on over-representation of old, mature females in upstream emergence traps towards the end of, or even after actual emergence periods. Criteria for age class discrimination of the respective taxa are described. The validity of the present and of other indirect evidence for directed adult flights and the significance of adult upstream displacement are discussed. Optical orientation cues are suggested. Females of Leuctra prima and Siphonoperla torrentium are shown to gain 25–50% dry weight by feeding in the terrestrial environment; general information indicates many other Plecoptera may be similar in this respect. Terrestrial adult life is shown to last for 3–8 weeks. This long time, evidence of important flight activity and feeding together suggest that the terrestrial phase is spent as an active adult, the inevitable risks of which may form an important control of population dynamics.  相似文献   

18.
We examined the roots of 27 epiphytic and terrestrial species of Piperaceae collected in primary and secondary habitats in Monteverde, Costa Rica. Terrestrial roots of only two of the nine Peperomia species, two of eight Piper species, and of Pothomorphe umbellatum contained internal vesicles and/or arbuscules. We did not find internal vesicles and/or arbuscules in 3024 cm of fine roots of epiphytic Piperaceae, even though 15% of these root segments had associated external typical glomalean hyphae. Glomus and Acaulospora spores, and Gigaspora auxiliary cells occurred in both canopy and terrestrial habitats. After inoculation of a low nutrient substrate, the facultatively epiphytic Peperomia costaricensis averaged 23% mycorrhizal root length. Relatively high atmospheric inputs of dissolved inorganic nutrients that alleviate the requirement for mycorrhizae, and heterogeneity of mycorrhiza inocula in the canopy may explain the absence of mycorrhizae from epiphytic Piperaceae. We suggest that the Piperaceae comprises predominantly facultatively mycotrophic species, and that facultative mycotrophism facilitates their radiation to the canopy.  相似文献   

19.
Palmar and plantar dermatoglyphic pattern types, area and total pattern intensities (API and TPI), and pattern intensity (PI) profiles are presented for the South American genus Cacajao of the subfamily Pitheciinae. The data are based on prints from 41 bald-head uacaries (C. calvus), 9 white bald-head uacaries (C. c. calvus), and 15 black-head uacaries (C. melanocephalus). In each extremity, loops of differing orientation were the most frequent pattern type; whorls were dominant at palmar interdigital (I) area 3 in C. calvus and at both I3 and I4 in C. melanocephalus. Open fields characterized the palmar thenar and plantar proximal hypothenar, thenar, calcar, and I3 and I4. There was little evidence of significant sexual dimorphism as assessed from PI values. The genus displayed significant asymmetry at palmar I3 (P?0.001) and plantar distal hypothenar (P?0.004). There were significant group differences between C. calvus and C. c. calvus in the palmar thenar API and plantar TPIs. The combined bald-head sample of C. calvus and C. c. calvus differed from C. melanocephalus in API of palmar I4 and plantar distal thenar, I2, and distal hypothenar (marginally), and in plantar TPIs. In PI profiles, C. melanocephalus departed from the pattern shared by C. calvus and C. c. calvus in both palmar and plantar interdigital areas. As a genus, the uacaries have markedly low plantar TPI values relative to palmar values (palm-sole index > 195). Of eight comparison cebid genera, only Chiropotes, another pitheciine genus, approximated these values.  相似文献   

20.
Prokaryotic Nostoc, one of the world's most conspicuous and widespread algal genera (similar to eukaryotic algae, plants, and animals) is known to support a microbiome that influences host ecological roles. Past taxonomic characterizations of surface microbiota (epimicrobiota) of free‐living Nostoc sampled from freshwater systems employed 16S rRNA genes, typically amplicons. We compared taxa identified from 16S, 18S, 23S, and 28S rRNA gene sequences filtered from shotgun metagenomic sequence and used microscopy to illuminate epimicrobiota diversity for Nostoc sampled from a wetland in the northern Chilean Altiplano. Phylogenetic analysis and rRNA gene sequence abundance estimates indicated that the host was related to Nostoc punctiforme PCC 73102. Epimicrobiota were inferred to include 18 epicyanobacterial genera or uncultured taxa, six epieukaryotic algal genera, and 66 anoxygenic bacterial genera, all having average genomic coverage ≥90X. The epicyanobacteria Geitlerinemia, Oscillatoria, Phormidium, and an uncultured taxon were detected only by 16S rRNA gene; Gloeobacter and Pseudanabaena were detected using 16S and 23S; and Phormididesmis, Neosynechococcus, Symphothece, Aphanizomenon, Nodularia, Spirulina, Nodosilinea, Synechococcus, Cyanobium, and Anabaena (the latter corroborated by microscopy), plus two uncultured cyanobacterial taxa (JSC12, O77) were detected only by 23S rRNA gene sequences. Three chlamydomonad and two heterotrophic stramenopiles genera were inferred from 18S; the streptophyte green alga Chaetosphaeridium globosum was detected by microscopy and 28S rRNA genes, but not 18S rRNA genes. Overall, >60% of epimicrobial taxa were detected by markers other than 16S rRNA genes. Some algal taxa observed microscopically were not detected from sequence data. Results indicate that multiple taxonomic markers derived from metagenomic sequence data and microscopy increase epimicrobiota detection.  相似文献   

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