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161.
We identified 11 polymorphic microsatellite markers for Alouatta caraya. Three markers were isolated from an enriched genomic library of A. caraya (AC14, AC17, AC45), five were previously described in Homo sapiens (TGMS1, TGMS2, D5S117, D8S165, D17S804), and three were identified for Lagothix lagotricha (1110, 1118, 157). Forty‐eight individuals from one Argentinean population were genotyped, yielding heterozygosity values between 0.146 and 0.792. These markers provide an exclusion power of 0.922 when neither parent is known (0.992 when one parent is known) and are suitable for parentage analysis, population genetics and phylogeographical studies of A. caraya, the southernmost primate in the New World.  相似文献   
162.
自林启彬先生1978年命名了我国第一个古生代昆虫至今, 中国学者共发表20余篇分类学论著, 描述鉴定我国古生代昆虫共61种, 归属于9目(总目)。这些标本分布于西北、 西南、 华东等9省区, 其中石炭纪47种, 二叠纪14种。本文统计了我国已发现的古生代化石昆虫属种名录以及它们的分布和地质年代, 总结了国内古生代化石昆虫当前的研究状况和发展趋势, 并分析了研究中存在的问题。其中关于化石昆虫普遍存在的脉序差异问题需给予足够的重视, 高级阶元的建立应更加慎重。研究表明我国古生代昆虫已经高度分异, 古翅类、 新翅类均已出现, 且代表着有翅昆虫辐射演化的重要阶段。  相似文献   
163.
Abstract: Examination of 387 serum samples from 41 primate species with two different ELISAs for the presence of IgG-antibodies against Epstein-Barr virus. Antibodies were detected in 15 out of 32 species of Old World primates and none in six species of New World primates by screening ELISA (Enzygnost, Behringwerke AG, Marburg), a testkit for human diagnostics. To avoid species-dependent factors which could influence the sensitivity of the Enzygnost assay, a competition ELISA was established. The modified test assessed antibodies in all species of Old World primates and three species of the New World primates.  相似文献   
164.
Aim  We examine the effect of island area on body dimensions in a single species of primate endemic to Southeast Asia, the long-tailed macaque ( Macaca fascicularis ). In addition, we test Allen's rule and a within-species or intraspecific equivalent of Bergmann's rule (i.e. Rensch's rule) to evaluate body size and shape evolution in this sample of insular macaques.
Location  The Sunda Shelf islands of Southeast Asia.
Methods  Body size measurements of insular macaques gathered from the literature were analysed relative to island area, latitude, maximum altitude, isolation from the mainland and other islands, and various climatic variables using linear regression.
Results  We found no statistically significant relationship between island area and body length or head length in our sample of insular long-tailed macaques. Tail length correlated negatively with island area. Head length and body length exhibited increases corresponding to increasing latitude, a finding seemingly consistent with the expression of Bergmann's rule within a single species. These variables, however, were not correlated with temperature, indicating that Bergmann's rule is not in effect. Tail length was not correlated with either temperature or increasing latitude, contrary to that predicted by Allen's rule.
Main conclusions  The island rule dictating that body size will covary with island area does not apply to this particular species of primate. Our study is consistent with results presented in the literature by demonstrating that skull and body length in insular long-tailed macaques do not, strictly speaking, conform to Rensch's rule. Unlike previous studies, however, our findings suggest that tail-length variation in insular macaques does not support Allen's rule.  相似文献   
165.
Vibrissae are specialized sensory “hairs” that respond to mechanical stimuli. Sensory information from vibrissae is transmitted to the brain via the infraorbital nerve, which passes through the infraorbital foramen (IOF). Several analyses have documented that primates have smaller IOFs than non-primate mammals, and that haplorhines have smaller IOFs than strepsirrhines. These grade shifts in IOF area were attributed to differences in “vibrissa development.” Following earlier analyses, IOF area has been used to derive a general estimate of “whiskeredness” in extinct primates, and consequently, IOF area has been used in phylogenetic and paleoecological interpretations. Yet, the relationship between IOF area and vibrissa count has not been tested, and little is known about how IOF area and vibrissa counts vary among mammals. This study explores how relative IOF area and vibrissa count differ among 25 mammalian orders, and tests for a correlation between IOF area and vibrissa count. Results indicate that primates and dermopterans (Primatomorpha) have smaller IOFs than most non-primate mammals, but they do not have fewer vibrissae. In addition, strepsirrhines and haplorhines do not differ from one another in relative IOF area or vibrissa counts. Despite different patterns documented for IOF area and vibrissa count variation across mammals, results from this study do confirm that vibrissa count and IOF area are significantly and positively correlated (p < 0.0001). However, there is considerable scatter in the data, suggesting that vibrissa counts cannot be predicted from IOF area. There are three implications of these finding. First, IOF area reflects all mechanoreceptors in the maxillary region, not just vibrissae. Second, IOF area may be an informative feature in interpretations of the fossil record. Third, paleoecological interpretations based on vibrissae are not recommended.  相似文献   
166.
The primate fossil record suggests that terrestriality was more common in the past than it is today, particularly among cercopithecoid primates. Whether or not a fossil primate habitually preferred terrestrial substrates has typically been inferred from its forelimb anatomy. Because extant large-bodied terrestrial cercopithecine monkeys utilize digitigrade hand postures during locomotion, being able to identify if a fossil primate habitually adopted digitigrade postures would be particularly revealing of terrestriality in this group. This paper examines the functional morphology of metacarpals in order to identify osteological correlates of digitigrade versus palmigrade hand postures. Linear measurements were obtained from 324 individuals belonging to digitigrade and palmigrade cercopithecoid species and comparisons were made between hand posture groups. Digitigrade taxa have shorter metacarpals, relative to both body mass and humerus length, than palmigrade taxa. Also, digitigrade taxa tend to have metacarpals with smaller dorsoventral diameters, relative to the product of body mass and metacarpal length, compared to palmigrade taxa. The size and shape of the metacarpal heads do not significantly differ between hand posture groups. Multivariate analyses suggest that metacarpal shape can only weakly discriminate between hand posture groups. In general, while there are some morphological differences in the metacarpals between hand posture groups, similarities also exist that are likely related to the fact that even digitigrade cercopithecoids can adopt palmigrade hand postures in different situations (e.g., terrestrial running, arboreal locomotion), and/or that the functional demands of different hand postures are not reflected in all aspects of metacarpal morphology. Therefore, the lack of identifiable adaptations for specific hand postures in extant cercopithecoids makes it difficult to determine a preference for specific habitats from fossil primate hand bones.  相似文献   
167.
Semple et al. (Semple et al. in press, Biol. Lett. (doi:10.1098/rsbl.2009.1062)) argued that the ‘law of brevity’ (an inverse relationship between word length and frequency of use) applies not only to human language but also to vocal signalling in non-human primates, because coding efficiency is paramount in both situations. We analysed the frequency of use of signals of different duration in the vocal repertoires of two Neotropical primate species studied in the wild—the common marmoset (Callithrix jacchus) and the golden-backed uakari (Cacajao melanocephalus). The key prediction of the law of brevity was not supported in either species: although the most frequently emitted calls were relatively brief, they were not the shortest signals in the repertoire. The costs and benefits associated with signals of different duration must be appreciated to understand properly their frequency of use. Although relatively brief vocal signals may be favoured by natural selection in order to minimize energetic costs, the very briefest signals may be ambiguous, contain reduced information or be difficult to detect or locate, and may therefore be selected against. Analogies between human language and vocal communication in animals can be misleading as a basis for understanding frequency of use, because coding efficiency is not the only factor of importance in animal communication, and the costs and benefits associated with different signal durations will vary in a species-specific manner.  相似文献   
168.
A detailed endocranial cast of the olfactory bulb of Amphipithecus mogaungensis, a latest middle Eocene primate from the Pondaung Formation (Myanmar), was studied in comparison with some Paleogene primates, the olfactory bulb of which has been reported. The olfactory bulb of Amphipithecus is located just anterior to the postorbital constriction, that is, within the interorbital septum. It is relatively large and pedunculate, not overlapped by the frontal lobe, and consists of two parallell aligned bodies. The relative volume of the olfactory bulb shows the same pattern as in adapiforms, but the location and bilobed form are more similar to those of omomyoids than of adapiforms. Electronic Publication  相似文献   
169.

Aim

Central Africa shelters diverse and iconic megafauna, which is threatened by climate and land-use changes and increased hunting-induced defaunation. Though crucial for coordinating regional conservation actions, how species assemblages are spatially structured remains poorly understood. This study aims to fill this knowledge gap for mammals across central African forests.

Location

Tropical moist forests from Nigeria to the Albertine Rift.

Methods

An extensive compilation of forest-dwelling mammal species lists was made from wildlife and bushmeat-related surveys across central Africa. A beta-diversity approach enabling the clustering of surveys composed of similar species was implemented to identify and delimit zoogeographic districts, separately for three well-documented mammal orders: carnivores, primates and artiodactyls. Random forest classification models were then used to identify the environmental determinants of the district's distribution and to produce a continuous zoogeographic map (and associated uncertainties) critical to assess the conservation status of each district and their ongoing threats.

Results

While carnivores do not present a clear spatial structure within central African forests, our findings highlight the structuring role of rivers on both primate and artiodactyl assemblages' distributions. We retained eight and six spatially congruent districts for primates and artiodactyls, respectively. These districts were shaped by the Ubangi-Congo River system, and the Cross and Sanaga Rivers, with a secondary role of insularity and precipitation identified for primates. Highly threatened districts were highlighted, especially in Nigeria and in the Democratic Republic of Congo, the latter including vast areas that are understudied and poorly represented in the protected area network.

Main Conclusions

Beyond refining our understanding of the diversity and uniqueness of mammalian assemblages across central African forests, our map of zoogeographic districts has far-reaching implications for the conservation of highly threatened taxa, allowing to target species and areas of interest for further sampling, conservation and rewilding efforts.  相似文献   
170.
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