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1.
Bonobos are large, highly mobile primates living in the relatively undisturbed, contiguous forest south of the Congo River. Accordingly, gene flow among populations is assumed to be extensive, but may be impeded by large, impassable rivers. We examined mitochondrial DNA control region sequence variation in individuals from five distinct localities separated by rivers in order to estimate relative levels of genetic diversity and assess the extent and pattern of population genetic structure in the bonobo. Diversity estimates for the bonobo exceed those for humans, but are less than those found for the chimpanzee. All regions sampled are significantly differentiated from one another, according to genetic distances estimated as pairwise FSTs, with the greatest differentiation existing between region East and each of the two Northern populations (N and NE) and the least differentiation between regions Central and South. The distribution of nucleotide diversity shows a clear signal of population structure, with some 30% of the variance occurring among geographical regions. However, a geographical patterning of the population structure is not obvious. Namely, mitochondrial haplotypes were shared among all regions excepting the most eastern locality and the phylogenetic analysis revealed a tree in which haplotypes were intermixed with little regard to geographical origin, with the notable exception of the close relationships among the haplotypes found in the east. Nonetheless, genetic distances correlated with geographical distances when the intervening distances were measured around rivers presenting effective current-day barriers, but not when straight-line distances were used, suggesting that rivers are indeed a hindrance to gene flow in this species. 相似文献
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A host of ecological, anatomical, and physiological selective pressures are hypothesized to have played a role in the evolution of hominid bipedalism. A referential model, based on the chimpanzee (Pan troglodytes) and bonobo (Pan paniscus), was used to test through experimental manipulation four hypotheses on the evolution of hominid bipedalism. The introduction of food piles (Carry hypothesis) increased locomotor bipedality in both species. Neither the introduction of branches (Display hypothesis) nor the construction of visual barriers (Vigilance hypothesis) altered bipedality in either species. Introduction of raised foraging structures (Forage hypothesis) increased postural bipedality in chimpanzees. These experimental manipulations provided support for carrying of portable objects and foraging on elevated food-items as plausible mechanisms that shaped bipedalism in hominids. 相似文献
3.
Y-chromosome analysis confirms highly sex-biased dispersal and suggests a low male effective population size in bonobos (Pan paniscus) 总被引:1,自引:0,他引:1
Eriksson J Siedel H Lukas D Kayser M Erler A Hashimoto C Hohmann G Boesch C Vigilant L 《Molecular ecology》2006,15(4):939-949
Dispersal is a rare event that is difficult to observe in slowly maturing, long-lived wild animal species such as the bonobo. In this study we used sex-linked (mitochondrial DNA sequence and Y-chromosome microsatellite) markers from the same set of individuals to estimate the magnitude of difference in effective dispersal between the sexes and to investigate the long-term demographic history of bonobos. We sampled 34 males from four distinct geographical areas across the bonobo distribution range. As predicted for a female-dispersing species, we found much higher levels of differentiation among local bonobo populations based upon Y-chromosomal than mtDNA genetic variation. Specifically, almost all of the Y-chromosomal variation distinguished populations, while nearly all of the mtDNA variation was shared between populations. Furthermore, genetic distance correlated with geographical distance for mtDNA but not for the Y chromosome. Female bonobos have a much higher migration rate and/or effective population size as compared to males, and the estimate for the mitochondrial TMRCA (time to most recent common ancestor) was approximately 10 times greater than the estimate for the Y chromosome (410,000 vs. 40,000-45,000). For humans the difference is merely a factor of two, suggesting a more stable demographic history in bonobos in comparison to humans. 相似文献
4.
D'Août K Aerts P De Clercq D De Meester K Van Elsacker L 《American journal of physical anthropology》2002,119(1):37-51
We describe segment angles (trunk, thigh, shank, and foot) and joint angles (hip, knee, and ankle) for the hind limbs of bonobos walking bipedally ("bent-hip bent-knee walking," 17 sequences) and quadrupedally (33 sequences). Data were based on video recordings (50 Hz) of nine subjects in a lateral view, walking at voluntary speed. The major differences between bipedal and quadrupedal walking are found in the trunk, thigh, and hip angles. During bipedal walking, the trunk is approximately 33-41 degrees more erect than during quadrupedal locomotion, although it is considerably more bent forward than in normal human locomotion. Moreover, during bipedal walking, the hip has a smaller range of motion (by 12 degrees ) and is more extended (by 20-35 degrees ) than during quadrupedal walking. In general, angle profiles in bonobos are much more variable than in humans. Intralimb phase relationships of subsequent joint angles show that hip-knee coordination is similar for bipedal and quadrupedal walking, and resembles the human pattern. The coordination between knee and ankle differs much more from the human pattern. Based on joint angles observed throughout stance phase and on the estimation of functional leg length, an efficient inverted pendulum mechanism is not expected in bonobos. 相似文献
5.
The endangered great ape, Pan paniscus (bonobo) has the smallest range of the African apes. Virtually nothing is known about the genetic diversity or genetic structure of this species, while substantial amounts of polymorphism have been reported for the bonobo’s widespread congener, the chimpanzee (P. troglodytes). Given its restricted range, what is the extent of genetic variation in the bonobo relative to the chimpanzee, and is the bonobo genetically depauperate? To investigate patterns of genetic polymorphism, bonobos of wild origin were genotyped for 28 microsatellite loci. The mean number of alleles per locus (5.2) and the mean observed heterozygosity (0.52) in bonobos were similar to variation observed in a wild chimpanzee community (P. t. schweinfurthii). The rarer bonobo is not genetically depauperate and may have genetic diversity comparable to the eastern chimpanzee subspecies. Bonobos have approximately 55% of the allelic diversity and 66% of the observed heterozygosity exhibited by all three chimpanzee subspecies sampled across equatorial Africa. Resampling techniques were used to quantify the effects of sample size differences and number and choice of loci between bonobos and chimpanzees. The examination of these variables underscores their importance in accurately interpreting interspecific comparisons of diversity estimates. 相似文献
6.
Kathryn C. Gamble Jill A. Moyse Jessica N. Lovstad Carole B. Ober Emma E. Thompson 《Zoo biology》2011,30(4):427-444
Blood groups of humans and great apes have long been considered similar, although they are not interchangeable between species. In this study, human monoclonal antibody technology was used to assign human ABO blood groups to whole blood samples from great apes housed in North American and European zoos and in situ managed populations, as a practical means to assist blood transfusion situations for these species. From a subset of each of the species (bonobo, common chimpanzee, gorilla, and orangutans), DNA sequence analysis was performed to determine blood group genotype. Bonobo and common chimpanzee populations were predominantly group A, which concurred with historic literature and was confirmed by genotyping. In agreement with historic literature, a smaller number of the common chimpanzees sampled were group O, although this O blood group was more often present in wild‐origin animals as compared with zoo‐born animals. Gorilla blood groups were inconclusive by monoclonal antibody techniques, and genetic studies were inconsistent with any known human blood group. As the genus and, specifically, the Bornean species, orangutans were identified with all human blood groups, including O, which had not been reported previously. Following this study, it was concluded that blood groups of bonobo, common chimpanzees, and some orangutans can be reliably assessed by human monoclonal antibody technology. However, this technique was not reliable for gorilla or orangutans other than those with blood group A. Even in those species with reliable blood group detection, blood transfusion preparation must include cross‐matching to minimize adverse reactions for the patient. Zoo Biol 30:427–444, 2011. © 2010 Wiley‐Liss, Inc. 相似文献
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Jefferson S. Hall Lee J. T. White Bila-Isia Inogwabini Ilambu Omari Hilary Simons Morland Elizabeth A. Williamson Kristin Saltonstall Peter Walsh Claude Sikubwabo Dumbo Bonny Kaleme Prince Kiswele Amy Vedder Kathy Freeman 《International journal of primatology》1998,19(2):207-235
We describe the distribution and estimate densities of Grauer's gorillas (Gorilla gorilla graueri) and eastern chimpanzees (Pan troglodytes schweinfurthi) in a 12,770-km
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area of lowland forest between the Lowa, Luka, Lugulu, and Oku rivers in eastern Democratic Republic of Congo, the site of the largest continuous population of Grauer's gorillas. The survey included a total of 480 km of transects completed within seven sampling zones in the Kahuzi-Biega National Park lowland sector and adjacent Kasese region and approximately 1100 km of footpath and forest reconnaissance. We estimate total populations of 7670 (4180–10,830) weaned gorillas within the Kahuzi-Biega lowland sector and 3350 (1420–5950) individuals in the Kasese survey areas. Within the same area, we estimate a population of 2600 (1620–4500) chimpanzees. Ape nest site densities are significantly higher within the Kahuzi-Biega lowland sector than in the more remote Kasese survey area in spite of a significantly higher encounter rate of human sign within the lowland sector of the park. Comparison of our data with information obtained by Emlen and Schaller during the first rangewide survey of Grauer's gorillas in 1959 suggests that gorilla populations have remained stable in protected areas but declined in adjacent forest. These findings underscore the key role played by national parks in protecting biological resources in spite of the recent political and economic turmoil in the region. We also show that forest reconnaissance is a reliable and cost-effective method to assess gorilla densities in remote forested areas. 相似文献
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Two new genera and species parasitizing passalid beetles from the Democratic Republic of Congo are described. Kongonema meyeri
gen. n. sp. n. is characterized by having females with the cervical cuticle unarmed, first cephalic annule cone-like and truncate, sub-cylindrical procorpus and genital tract didelphic-amphidelphic. The males of Kongonema meyeri
gen. n. sp. n. have the procorpus sub-cylindrical, the dorsal cuticle of the tail end thickened, a single large, median mammiform pre-cloacal papilla and a pair of small, pre-cloacal, sub-lateral papillae at a short distance before the level of the cloaca. Lubanema decraemerae
gen. n. sp. n. is characterized by the body markedly fusiform, cuticle unarmed and strongly annulated, procorpus sub-cylindrical, isthmus as a constriction between procorpus and basal bulb, genital tract monodelphic-prodelphic and the posterior end rounded with a very short tail appendage. 相似文献
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Two new genera and species parasitizing passalid beetles from the Democratic Republic of Congo are described. Batwanema congo
gen. n. et sp. n. is characterized by having females with the cervical cuticle armed with scale-like projections, arranged initially in rows of eight elements that gradually divide and form pointed spines toward the end of the spiny region, two cephalic annuli, clavate procorpus and genital tract monodelphic-prodelphic. Two Malagasian species of Artigasia Christie, 1934 were placed in this genus as B. latum (Van Waerebeke, 1973) comb. n. and B. annulatum (Van Waerebeke, 1973) comb. n.
Chokwenema lepidophorum
gen. n. et sp. n. is characterized by having females with the cervical cuticle armed with scale-like projections, arranged initially in rows of eight elements (similar to Batwanema) that divide gradually, forming spines; a single cephalic annule cone-like, truncated, moderately inflated; procorpus sub-cylindrical and genital tract didelphic-amphidelphic. 相似文献
12.
The use and control of fire are uniquely human traits thought to have come about fairly late in the evolution of our lineage, and they are hypothesized to correlate with an increase in intellectual complexity. Given the relatively sophisticated cognitive abilities yet small brain size of living apes compared to humans and even early hominins, observations of wild chimpanzees' reactions to naturally occurring fire can help inform hypotheses about the likely responses of early hominins to fire. We use data on the behavior of savanna chimpanzees (Pan troglodytes verus) at Fongoli, Senegal during two encounters with wildfires to illuminate the similarities between great apes and humans regarding their reaction to fire. Chimpanzees' close relatedness to our lineage makes them phylogenetically relevant to the study of hominid evolution, and the open, hot and dry environment at Fongoli, similar to the savanna mosaic thought to characterize much of hominid evolution, makes these apes ecologically important as a living primate model as well. Chimpanzees at Fongoli calmly monitor wildfires and change their behavior in anticipation of the fire's movement. The ability to conceptualize the “behavior” of fire may be a synapomorphic trait characterizing the human‐chimpanzee clade. If the cognitive underpinnings of fire conceptualization are a primitive hominid trait, hypotheses concerning the origins of the control and use of fire may need revision. We argue that our findings exemplify the importance of using living chimpanzees as models for better understanding human evolution despite recently published suggestions to the contrary. Am J Phys Anthropol, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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The first species of the small Afrotropical family Ammodesmidae discovered in central Africa (Democratic Republic of the Congo) belongs to the genus Ammodesmus Cook, 1896, which was hitherto known only from two species in western Africa. A key is given to incorporate Ammodesmus
congoensis sp. n., a species also showing an evident sex dimorphism: ♂ densely hirsute, ♀ with much longer and sparser tergal setae. 相似文献
14.
Sharon L. Deem Fiona Maisels Richard G. Robbins 《European Journal of Wildlife Research》2005,51(1):60-62
A field necropsy was performed on a recently dead adult forest buffalo, Syncerus caffer nanus, found in the Nouabalé-Ndoki National Park, Republic of Congo. Based on the gross and histological lesions, the cause of death was determined to be conspecific fighting. Ectoparasites collected from this forest buffalo were Amblyomma sp. (larvae) and Rhipicephalus ziemanni Neumann. Endoparasites collected included a paramphistomid trematode, Carmyerius gregarius, and oocysts of Eimeria spp., paramphistomid eggs (presumably from C. gregarius), metastrongylid lungworm larvae, and strongylid eggs. Parasitic findings from this forest buffalo were compared to previous reports from savanna and forest buffalo. 相似文献
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Jean-Marie Le Tensorer Hélène Le Tensorer Pietro Martini Vera von Falkenstein Peter Schmid Juan José Villalain 《L'Anthropologie》2015,119(5):581-594
At present, the oldest traces of human cultures are found in Eastern Africa. New discoveries set anew the questions about human and animal dispersal into Eurasia. For over 1.8 million years, humans have been present in the Levant. An extensive program of surveys and excavations in the Syrian Desert showed that this part of the world was a very ancient land of settlement. In Central Syria, the oldest site, Aïn al Fil in the region of El Kowm, was excavated in 2008 and 2010. The lithic industry in the lowest layer can be characterized by numerous unretouched flakes, pebble-tools and core-like artefacts. This assemblage is typical in a broad sense of archaic Palaeolithic the debitage of which corresponds to mode 1. From a techno-typological point of view, this industry tallies quite well with the so-called Oldowan stage. It shows remarkable similarities with the oldest African assemblages. From a chronologic point of view, these levels occur before three positive events in the Matuyama paleomagnetic sequence. It seems consistent to place the Oldowan sequence around 1.8 Ma BP within the Olduvai subchron or just before Olduvai/Matuyama reversal limit. Together with those of the neighbouring site Hummal, these levels would be the oldest traces of human presence ever found in Syria. In the Levant, the first humans not only occupied favourable zones but regularly ventured deep into less welcoming environments suggesting an astonishing flexibility in their behavioural and survival skills. 相似文献
16.
The Forest Stewardship Council developed the concept of High Conservation Values (HCVs) as a criteria in the forest certification process in order to promote sustainable forest management. It has six major components or values and component one and two of HCVs deal with the habitat for viable populations of “rare, endemic and threatened (RET) species” using the IUCN Red List category and other national / regional / local lists. But a consistent robust methodology for identification of these areas, does not exist. The present study tried to develop for the first time, a straight forward inclusive methodology for identification of HCVAs for the RET species on a spatio-temporal scale. A total of 50 RET and other significant species (32 flora, 10 fauna and 8 avifauna) were identified after a thorough literature review, field surveys and consultations with experts. Occurrence data of the selected species was collected from different secondary sources, field surveys, institutes and scientists who have worked on them. A 10 km grid-based approach and stratified random sampling was used for the primary GPS field surveys conducted during 2018–2019. MaxEnt species distribution model (SDM) software was used based on the occurrence data and environmental variables for identification of potential suitable habitats for the selected species. Linear support vector machine (LSVM) model was used for assessing the performance of the SDMs. The performance of each SDM has been validated through Cohen's Kappa (KAPPA), true skill statistic (TSS) and receiver operating characteristics (ROC) models. The proposed methodology addresses the urgent need for a holistic and robust set of techniques to apply the HCV toolkit. This is key to identify and map HCVAs for RET species at the landscape level and can be easily adapted to and adopted at the national, regional, state or local level in India. The methods offer an efficient, reliable approach for the application of the HCV concept, elsewhere in the world. 相似文献
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Mexico hosts the highest species richness of pines (Pinus, Pinaceae) worldwide; however, the priority areas for their conservation in the country are unknown. In this study, the ecological niche of the 50 native pine species was modeled. Then, through a multi-criteria analysis, the priority areas for the conservation of the genus Pinus were identified according to the spatial patterns of richness, geographic rareness, irreplaceability, the level of vulnerability of their habitat and the status of legal protection. The results revealed that the regions with high species richness differed from those with high endemism. Also, most pine species have undergone processes of habitat degradation, having been the endemic species the most affected. The priority areas covered regions with high species richness, high endemism, and highly degraded forests, located at mountainous portions of the Baja California Peninsula, the Sierra Madre Occidental, the Sierra Madre Oriental, the Trans-Mexican Volcanic Belt, and the Sierra Madre del Sur. A low proportion of priority areas overlapped with protected areas or terrestrial regions considered priorities for biological conservation. These results suggest that conservation efforts for this genus should be focused beyond regions with high species richness and current protected areas. Besides, the priority areas identified in this study can be the basis to create biological corridors and new protected areas, which could contribute significantly to the conservation of this genus in Mexico. 相似文献
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Zheng Meng Nateka L. Jackson Oleg D. Shcherbakov Hyoungsoo Choi Scott W. Blume 《Journal of cellular biochemistry》2010,110(2):531-544
IGF1R is a proto‐oncogene with potent mitogenic and antiapoptotic activities, and its expression must be tightly regulated to maintain normal cellular and tissue homeostasis. We previously demonstrated that translation of the human IGF1R mRNA is controlled by an internal ribosome entry site (IRES), and delimited the core functional IRES to a 90‐nucleotide segment of the 5′‐untranslated region positioned immediately upstream of the initiation codon. Here we have analyzed the sequence elements that contribute to the function of the core IRES. The Stem2/Loop2 sequence of the IRES exhibits near‐perfect Watson–Crick complementarity to the G961 loop (helix 23b) of the 18S rRNA, which is positioned within the E‐site on the platform of the 40S ribosomal subunit. Mutations that disrupt this complementarity have a negative impact on regulatory protein binding and dramatically decrease IRES activity, suggesting that the IGF1R IRES may recruit the 40S ribosome by a eukaryotic equivalent of the Shine–Dalgarno (mRNA–rRNA base‐pairing) interaction. The homopolymeric Loop3 sequence of the IRES modulates accessibility and limits the rate of translation initiation mediated through the IRES. Two functionally distinct allelic forms of the Loop3 poly(U)‐tract are prevalent in the human population, and it is conceivable that germ‐line or somatic variations in this sequence could predispose individuals to development of malignancy, or provide a selectable growth advantage for tumor cells. J. Cell. Biochem. 110: 531–544, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
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Position 170 of Rabbit Na+/glucose cotransporter (rSGLT1) lies in the Na+ pathway; modulation of polarity/charge at this site regulates charge transfer and carrier turnover
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Positions 163, 166, and 173, within the putative external loop joining transmembrane segments IV and V of rabbit Na(+)/glucose cotransporter, form part of its Na(+) interaction and voltage-sensing domain. Since a Q170C mutation within this region exhibits anomalous behavior, its function was further investigated. We used Xenopus oocytes coinjected with mouse T-antigen to enhance Q170C expression, and the two-microelectrode voltage-clamp technique. For Q170C, alpha-methyl D-glucopyranoside, phloridzin, and Na(+) affinity values are equivalent to those of wild-type; but turnover is reduced approximately 50%. Decreased [Na(+)] reduces Q170C, but not wild-type, charge transfer. Q170C presteady-state currents exhibit three time constants, tau, identical to wild-type. MTSES decreases maximal alpha-methyl D-glucopyranoside-induced currents by approximately 64% and Na(+) leak by approximately 55%; phloridzin and Na(+) affinity are unchanged. MTSES also reduces charge transfer (dithiothreitol-reversible) and Q170C turnover by approximately 60-70%. MTSEA and MTSET protect against MTSES, but neither affect Q170C function. MTSES has no obvious effect on the tau-values. Q170A behaves the same as Q170C. The mutation Q170E affects voltage sensitivity and reduces turnover, but also appears to influence Na(+) interaction. We conclude that 1), glutamine 170 lies in the Na(+) pathway in rabbit Na(+)/glucose cotransporter and 2), altered polarity and charge at position 170 affect a cotransporter conformational state and transition, which is rate-limiting, but probably not associated with empty carrier reorientation. 相似文献