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Accurate estimates of mass and size are important in a wide range of research questions in population and evolutionary biology, and yet such data are still rare for wild primates. This study presents detailed longitudinal data from a large population of wild indriids, and demonstrates links between fluctuations in body mass, environmental cycles, and reproduction. Understanding these links is a necessary step toward explaining the function and evolution of distinctive features of lemur biology and behavior.During the first 12 years of an ongoing study of the sifaka, Propithecus verreauxi verreauxi, at Beza Mahafaly in southwest Madagascar, 320 animals were captured and weighed throughout the year. Adult males and females exhibit seasonal cycles of mass loss, with females losing significantly more mass than males. In 2 drought years this pattern was especially pronounced. Compared to lighter females, females who were heavier at the time of the mating season were more likely to give birth in the following birth season. By showing (1) seasonally greater mass loss in reproductive females compared to males, particularly in drought years, (2) a close link between female mass and fertility, and (3) an uncoupling of the periods of highest body mass and of gestation and lactation, these results suggest that energy acquisition and storage are critically important in the life history strategies of female sifaka, and that "capital breeding" may be a feature of sifaka reproductive strategies. 相似文献
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J. I. Pollock I. D. Constable R. A. Mittermeier J. Ratsirarson H. Simons 《International journal of primatology》1985,6(4):435-447
In the course of a 4-day expedition to the island of Nosy Mangabe in northeastern Madagascar, two aye-ayes were separately
sighted, observed feeding and moving, and photographed. These observations confirm recent reports of the continued existence
of aye-ayes on the island following the translocation of nine individuals from the mainland in 1967. An adult male aye-aye
was seen feeding on the gall-like growths covering much of the bark surface of an Afzelia bijugatree and eating the insects these contained. The same individual also fed briefly on shoots of the bamboo Bambusa vulgaris. 相似文献
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J. Ratsirarson J. Anderson S. Warter Y. Rumpler 《Primates; journal of primatology》1987,28(1):119-122
The superfamily Lemuridae, which includes some of the most primitive extant primates, is confined to the island of Madagascar.
The speciesL. septentrionalis lives in the north of Madagascar. The geographical distribution of each of the four recognized subspecies is fairly well
defined except for the southern limits of the southernmost subspecies, namelyL. s. andrafiamenensis. Similarly the southern and northern limits of distribution ofL. mustelinus are uncertain. Two expeditions were carried out, one in the south of the Andrafiamena mountain chain, the other in the north
of the eastern forest, south of Vohemar to gain new information concerning the present southern limits ofL. septentrionalis and northern limit ofL. mustelinus. L. s. andrafiamenensis was found to the left of the Ambilobe-Vohemar road from Betsiaka to Maromokotra and on the left bank of the river Loky, to
the coast.L. mustelinus was found only on the right bank of the river Lokoho to the coast. Both survey indicate smaller ranges than those indicated
in recent publications, probably a result of continued human encroachment. 相似文献
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William J. Bond John A. Silander Jr Jeannin Ranaivonasy Joelisoa Ratsirarson 《Journal of Biogeography》2008,35(10):1743-1758
Aim Grasslands and savannas, which make up > 75% of Madagascar’s land area, have long been viewed as anthropogenically derived after people settled on the island c. 2 ka. We investigated this hypothesis and an alternative – that the grasslands are an insular example of the post‐Miocene spread of C4 grassy biomes world‐wide. Location Madagascar, southern Africa, East Africa. Methods We compared the number of C4 grass genera in Madagascar with that in southern and south‐central African floras. If the grasslands are recent we would expect to find fewer species and genera in Madagascar relative to Africa and for these species and genera to have very wide distribution ranges in Madagascar. Secondly, we searched Madagascan floras for the presence of endemic plant species or genera restricted to grasslands. We also searched for evidence of a grassland specialist fauna with species endemic to Madagascar. Plant and animal species endemic to C4 grassy biomes would not be expected if these are of recent origin. Results Madagascar has c. 88 C4 grass genera, including six endemic genera. Excluding African genera with only one or two species, Madagascar has 86.6% of southern Africa’s and 89.4% of south‐central Africa’s grass genera. C4 grass species make up c. 4% of the flora of both Madagascar and southern Africa and species : genus ratios are similar (4.3 and 5.1, respectively). Turnover of grasses along geographical gradients follows similar patterns to those in South Africa, with Andropogoneae dominating in mesic biomes and Chlorideae in semi‐arid grassy biomes. At least 16 monocot genera have grassland members, many of which are endemic to Madagascar. Woody species in frequently burnt savannas include both Madagascan endemics and African species. A different woody flora, mostly endemic, occurs in less frequently burnt grasslands in the central highlands, filling a similar successional niche to montane C4 grasslands in Africa. Diverse vertebrate and invertebrate lineages have grassland specialists, including many endemic to Madagascar (e.g. termites, ants, lizards, snakes, birds and mammals). Grassland use of the extinct fauna is poorly known but carbon isotope analysis indicates that a hippo, two giant tortoises and one extinct lemur ate C4 or CAM (crassulacean acid metabolism) plants. Main conclusions The diversity of C4 grass lineages in Madagascar relative to that in Africa, and the presence of plant and animal species endemic to Madagascan grassy biomes, does not fit the view that these grasslands are anthropogenically derived. We suggest that grasslands invaded Madagascar after the late Miocene, part of the world‐wide expansion of C4 grassy biomes. Madagascar provides an interesting test case for biogeographical analysis of how these novel biomes assembled, and the sources of the flora and fauna that now occupy them. A necessary part of such an analysis would be to establish the pre‐settlement extent of the C4 grassy biomes. Carbon isotope analysis of soil organic matter would be a feasible method for doing this. 相似文献
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Chromosomal evolution in Malagasy lemurs. IX. Chromosomal banding studies of Lepilemur mustelinus, L. dorsalis, and L. edwardsi 总被引:1,自引:0,他引:1
Y Rumpler B Ishak B Dutrillaux S Warter J Ratsirarson 《Cytogenetics and cell genetics》1986,42(3):164-168
The karyotypes of three Lepilemuridae species, Lepilemur mustelinus, L. edwardsi, and L. dorsalis, are described and compared to those of three Lepilemur species previously reported. The phylogenetic relationships between the six species and their presumed last common ancestor are given. The results obtained, and the comparison with other groups, strongly suggest a monophyletic origin for all Malagasy lemurs. 相似文献
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Cuozzo FP Sauther ML Yamashita N Lawler RR Brockman DK Godfrey LR Gould L Youssouf IA Lent C Ratsirarson J Richard AF Scott JR Sussman RW Villers LM Weber MA Willis G 《American journal of primatology》2008,70(4):363-371
Chemical deterioration of teeth is common among modern humans, and has been suggested for some extinct primates. Dental erosion caused by acidic foods may also obscure microwear signals of mechanical food properties. Ring-tailed lemurs at the Beza Mahafaly Special Reserve (BMSR), Madagascar, display frequent severe tooth wear and subsequent tooth loss. In contrast, sympatric Verreaux's sifaka display far less tooth wear and infrequent tooth loss, despite both species regularly consuming acidic tamarind fruit. We investigated the potential impact of dietary acidity on tooth wear, collecting data on salivary pH from both species, as well as salivary pH from ring-tailed lemurs at Tsimanampesotse National Park, Madagascar. We also collected salivary pH data from ring-tailed lemurs at the Indianapolis Zoo, none of which had eaten for at least 12 hr before data collection. Mean salivary pH for the BMSR ring-tailed lemurs (8.098, n=41, SD=0.550) was significantly more alkaline than Verreaux's sifaka (7.481, n=26, SD=0.458). The mean salivary pH of BMSR (8.098) and Tsimanampesotse (8.080, n=25, SD=0.746) ring-tailed lemurs did not differ significantly. Salivary pH for the Indianapolis Zoo sample (8.125, n=16, SD=0.289) did not differ significantly from either the BMSR or Tsimanampesotse ring-tailed lemurs, but was significantly more alkaline than the BMSR Verreaux's sifaka sample. Regardless of the time between feeding and collection of pH data (from several minutes to nearly 1 hr), salivary pH for each wild lemur was above the "critical" pH of 5.5, below which enamel demineralization occurs. Thus, the high pH of lemur saliva suggests a strong buffering capacity, indicating the impact of acidic foods on dental wear is short-lived, likely having a limited effect. However, tannins in tamarind fruit may increase friction between teeth, thereby increasing attrition and wear in lemurs. These data also suggest that salivary pH varies between lemur species, corresponding to broad dietary categories. 相似文献
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Richard R. Lawler Hal Caswell Alison F. Richard Joelisoa Ratsirarson Robert E. Dewar Marion Schwartz 《Oecologia》2009,161(3):491-504
In this study, we use deterministic and stochastic models to analyze the demography of Verreaux’s sifaka (Propithecus verreauxi verreauxi) in a fluctuating rainfall environment. The model is based on 16 years of data from Beza Mahafaly Special Reserve, southwest
Madagascar. The parameters in the stage-classified life cycle were estimated using mark-recapture methods. Statistical models
were evaluated using information-theoretic techniques and multi-model inference. The highest ranking model is time-invariant,
but the averaged model includes rainfall-dependence of survival and breeding. We used a time-series model of rainfall to construct
a stochastic demographic model. The time-invariant model and the stochastic model give a population growth rate of about 0.98.
Bootstrap confidence intervals on the growth rates, both deterministic and stochastic, include 1. Growth rates are most elastic
to changes in adult survival. Many demographic statistics show a nonlinear response to annual rainfall but are depressed when
annual rainfall is low, or the variance in annual rainfall is high. Perturbation analyses from both the time-invariant and
stochastic models indicate that recruitment and survival of older females are key determinants of population growth rate. 相似文献
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Diane K. Brockman Laurie R. Godfrey Luke J. Dollar Joelisoa Ratsirarson 《International journal of primatology》2008,29(1):135-152
Increasing evidence supports the idea that endemic avian and mammalian predators have profoundly impacted primate populations
in Madagascar (Goodman, S. M. Predation on lemurs. In S. M. Goodman, & J. P. Benstead (Eds.), The natural history of Madagascar (pp. 1221–1228). Chicago: University of Chicago Press, (2003).). The role in regulating lemur populations of the 3 introduced
mammalian carnivorans —small Indian civets (Viverricula indica, Desmarest 1804), domestic dogs (Canis lupus familiaris, Linnaeus 1758), and invasive wildcats (Felis silvestris, Schreber 1775)— is less clear, but recent evidence suggests that the latter 2 are becoming important predators of diurnal
lemurs. We report evidence for invasive wildcat predation on sifaka (Propithecus verreauxi verreauxi) in Parcel 1 at Beza Mahafaly Special Reserve, Madagascar, including skeletal remains of apparent Propithecus sifaka victims, observations of wildcat predatory behavior, and behavioral responses of the lemurs in the presence of wildcats. 相似文献
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