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21.
Björn M. Siemers Holger R. Goerlitz Eric Robsomanitrandrasana Marcus Piep Jean-Baptiste Ramanamanjato Daniel Rakotondravony Olga Ramilijaona Jörg U. Ganzhorn 《International journal of primatology》2007,28(2):291-304
Very little is known about how nocturnal primates find their food. Here we studied the sensory basis of food perception in
wild-caught gray mouse lemurs (Microcebus murinus) in Madagascar. Mouse lemurs feed primarily on fruit and arthropods. We established a set of behavioral experiments to assess
food detection in wild-born, field-experienced mouse lemurs in short-term captivity. Specifically, we investigated whether
they use visual, auditory, and motion cues to find and to localize prey arthropods and further whether olfactory cues are
sufficient for finding fruit. Visual cues from motionless arthropod dummies were not sufficient to allow reliable detection
of prey in choice experiments, nor did they trigger prey capture behavior when presented on the feeding platform. In contrast,
visual motion cues from moving prey dummies attracted their attention. Behavioral observations and experiments with live and
recorded insect rustling sounds indicated that the lemurs make use of prey-generated acoustic cues for foraging. Both visual
motion cues and acoustic prey stimuli on their own were sufficient to trigger approach and capture behavior in the mouse lemurs.
For the detection of fruit, choice experiments showed that olfactory information was sufficient for mouse lemurs to find a
piece of banana. Our study provides the first experimental data on the sensory ecology of food detection in mouse lemurs.
Further research is necessary to address the role of sensory ecology for food selection and possibly for niche differentiation
between sympatric Microcebus species. 相似文献
22.
Michela Balestri Marta Barresi Marco Campera Valentina Serra Jean Baptiste Ramanamanjato Michael Heistermann Giuseppe Donati 《PloS one》2014,9(9)
The littoral forest on sandy soil is among the most threatened habitats in Madagascar and, as such, it represents a hot-spot within a conservation hot-spot. Assessing the health of the resident lemur fauna is not only critical for the long-term viability of these populations, but also necessary for the future re-habilitation of this unique habitat. Since the Endangered collared brown lemur, Eulemur collaris, is the largest seed disperser of the Malagasy south-eastern littoral forest its survival in this habitat is crucial. In this study we compared fecal glucocorticoid metabolite (fGCM) levels, a measure of physiological stress and potential early indicator of population health, between groups of collared brown lemurs living in a degraded forest fragment and groups occurring in a more preserved area. For this, we analysed 279 fecal samples collected year-round from 4 groups of collared brown lemurs using a validated 11-oxoetiocholanolone enzyme immunoassay and tested if fGCM levels were influenced by reproductive stages, phenological seasons, sex, and habitat degradation. The lemurs living in the degraded forest had significantly higher fGCM levels than those living in the more preserved area. In particular, the highest fGCM levels were found during the mating season in all animals and in females during gestation in the degraded forest. Since mating and gestation are both occurring during the lean season in the littoral forest, these results likely reflect a combination of ecological and reproductive pressures. Our findings provide a clear indication that habitat degradation has additive effects to the challenges found in the natural habitat. Since increased stress hormone output may have long-term negative effects on population health and reproduction, our data emphasize the need for and may add to the development of effective conservation plans for the species. 相似文献
23.
Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
24.
25.
Vidushi S Patel Steven JB Cooper Janine E Deakin Bob Fulton Tina Graves Wesley C Warren Richard K Wilson Jennifer AM Graves 《BMC biology》2008,6(1):34
Background
Vertebrate alpha (α)- and beta (β)-globin gene families exemplify the way in which genomes evolve to produce functional complexity. From tandem duplication of a single globin locus, the α- and β-globin clusters expanded, and then were separated onto different chromosomes. The previous finding of a fossil β-globin gene (ω) in the marsupial α-cluster, however, suggested that duplication of the α-β cluster onto two chromosomes, followed by lineage-specific gene loss and duplication, produced paralogous α- and β-globin clusters in birds and mammals. Here we analyse genomic data from an egg-laying monotreme mammal, the platypus (Ornithorhynchus anatinus), to explore haemoglobin evolution at the stem of the mammalian radiation. 相似文献26.
Timothy M. Eppley Michela Balestri Marco Campera Johny Rabenantoandro Jean-Baptiste Ramanamanjato Faly Randriatafika Jörg U. Ganzhorn Giuseppe Donati 《International journal of primatology》2017,38(2):338-357
Primate responses to habitat alteration vary depending on the species’ dietary guild and forest type. Leaves from secondary vegetation can provide nutritious resources to folivorous primates, whereas frugivores, burdened with a scattered spatial and temporal distribution of fruiting resources, require larger home ranges, potentially limiting their ability to cope with altered landscapes. Within coastal southeastern Madagascar, we sought to determine whether two lemur species occupying contrasting ecological niches respond differently to the changing features of their degraded and fragmented habitat. We conducted behavioral observations between 2011 and 2013 on frugivorous collared brown lemurs (Eulemur collaris) and folivorous southern bamboo lemurs (Hapalemur meridionalis). To estimate the ability of lemurs to use pioneer species, we categorized all plants used for feeding and resting as fast growing, mid-growing, or slow growing. We fitted general linear mixed-effects models, one for each plant growth category with monthly proportional use rates as the dependent variable, and included species (E. collaris and H. meridionalis), activity (feeding and resting), and season (dry and wet) as fixed effects. Our results show that E. collaris used both slow- and mid-growing plant species most often, while H. meridionalis were more likely to use fast-growing plants, which indicated an ability to use secondary/disturbed vegetation. Frugivorous E. collaris appear more limited by climax plants, while folivorous H. meridionalis appear to be slightly more adaptable, a finding that is consistent with that for other primate folivores. 相似文献
27.
Jean-Baptiste Ramanamanjato Peter B. Mcintyre Ronald A. Nussbaum 《Biodiversity and Conservation》2002,11(10):1791-1807
Ambatorongorongo Mountain lies at the historical intersection betweenhumid, spiny, and littoral forests in southeastern Madagascar. We report theresults of surveys of the herpetofauna and lemurs occurring in Malahelo Forest,a small (<25 ha) forest fragment lying on the western slope ofAmbatorongorongo Mountain. There are at least 41 reptile, 11 amphibian, and 7lemur species in this forest, including several that are endemic to southeasternMadagascar and are at severe risk of extinction. The species richness of theMalahelo fauna is comparable to that of even the largest forest reserves in theregion. We also evaluate the similarity of the Malahelo herpetofauna to that ofnearby humid, spiny, and littoral forests to assess the biogeographic affinitiesof its amphibians and reptile assemblages. Both groups contain speciescharacteristic of each of the three surrounding forest types, but thebiogeographic patterns appear to differ for amphibians and reptiles. Overall,the herpetofauna and lemurs of the Malahelo Forest indicate that it is a remnantof a biogeographic transition zone between the major forest types ofsoutheastern Madagascar. The combination of high species richness, regionalendemics, and unique herpetofaunal and lemur assemblages should make MalaheloForest a high conservation priority, and we give recommendations for protectingwhat remains of this important transitional forest. 相似文献
28.
Hierarchical analysis of variation in the mitochondrial 16S rRNA gene among Hymenoptera 总被引:5,自引:2,他引:3
Nucleotide sequences from a 434-bp region of the 16S rRNA gene were
analyzed for 65 taxa of Hymenoptera (ants, bees, wasps, parasitoid wasps,
sawflies) to examine the patterns of variation within the gene fragment and
the taxonomic levels for which it shows maximum utility in phylogeny
estimation. A hierarchical approach was adopted in the study through
comparison of levels of sequence variation among taxa at different
taxonomic levels. As previously reported for many holometabolous insects,
the 16S data reported here for Hymenoptera are highly AT-rich and exhibit
strong site-to-site variation in substitution rate. More precise estimates
of the shape parameter (alpha) of the gamma distribution and the proportion
of invariant sites were obtained in this study by employing a reference
phylogeny and utilizing maximum-likelihood estimation. The effectiveness of
this approach to recovering expected phylogenies of selected hymenopteran
taxa has been tested against the use of maximum parsimony. This study finds
that the 16S gene is most informative for phylogenetic analysis at two
different levels: among closely related species or populations, and among
tribes, subfamilies, and families. Maximization of the phylogenetic signal
extracted from the 16S gene at higher taxonomic levels may require
consideration of the base composition bias and the site-to-site rate
variation in a maximum-likelihood framework.
相似文献
29.
This report describes a convenient method for the rapid and efficient
release of N-linked oligosaccharides from low microgram amounts of
glycoproteins. A 96-well MultiScreen assay system containing a
polyvinylidene difluoride (PVDF) membrane is employed to immobilize
glycoproteins for subsequent enzymatic deglycosylation. Recombinant
tissue-type plasminogen activator (rt-PA) is used to demonstrate the
deglycosylation of 0.1-50 micrograms of a glycoprotein. This method enabled
the recovery of a sufficient amount of N-linked oligosaccharides released
enzymatically with peptide N-glycosidase F (PNGaseF) from as little as 0.5
microgram rt-PA for subsequent analysis by matrix-assisted laser
desorption/ionization time-of-flight (MALDI- TOF) mass spectrometry. The
immobilization of rt-PA to the PVDF membrane did not sterically inhibit the
PNGaseF-mediated release of oligosaccharides from rt-PA as determined by
tryptic mapping experiments. Comparison of the oligosaccharides released
from 50 micrograms of rt-PA by either the 96-well plate method or by a
standard solution digestion procedure showed no significant differences in
the profiles obtained by high-pH anion-exchange chromatography with pulsed
amperometric detection (HPAEC-PAD). Both neutral and sialylated
oligosaccharide standards spiked into wells were recovered equally as
determined by HPAEC-PAD. One advantage of this approach is that reduction
and alkylation can be performed on submicrogram amounts of glycoproteins
with easy removal of reagents prior to PNGaseF digestion. In addition, this
method allows 60 glycoprotein samples to be deglycosylated in 1 day with
MALDI-TOF or HPAEC-PAD analysis being performed on the following day.
相似文献
30.
Deshpande NV Sabaté M Ligthart JM Kutryk MJ Serruys PW 《International journal of cardiovascular interventions》1998,1(1):45-48
Jailing of a side-branch is a known complication of stent implantation, and makes access to the side-branch difficult, especially if the stent is of the self-expanding type. Although plain balloon angioplasty is feasible for the jailed side-branches, the use of newer devices (a stent, Rotablation or atherectomy) has not been described. We describe a novel way of treating a side-branch jailed by a self-expanding stent by using stent implantation through the strut of a self-expanding stent. 相似文献