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1.
Peiyan Wong Christine E. Collins Jon H. Kaas 《International journal of primatology》2010,31(6):1002-1031
Tarsiers form the sister taxon to anthropoid primates, and their brains possess a mix of primitive and specialized features.
We describe architectonically distinct subdivisions of the somatosensory, auditory, and visual systems for tarsiers, as well
as nocturnal New World owl monkeys (Aotus) and strepsirhine galagos (Otolemur) for comparison. In general, the dorsal column nuclei, the ventroposterior nucleus, and primary somatosensory cortex are
somewhat less distinctly differentiated in tarsiers, suggesting that the somatosensory system is less specialized for somatosensory
processing. Although the inferior colliculus and the medial geniculate complex of the auditory system are architectonically
similar across the 3 primates, the primary auditory cortex of tarsiers is more distinct, suggesting a greater role in auditory
cortical processing. In the visual system, the differentiation of the superior colliculus is similar in all 3 primates, whereas
the laminar pattern in the lateral geniculate nucleus and the subdivisions of the inferior pulvinar in tarsiers resemble those
of anthropoid primates rather than strepsirhines, in agreement with the evidence that tarsiers form the sister clade for anthropoids.
In addition, primary visual cortex has more distinct sublayers in tarsiers than other primates, attesting to its importance
in this visual predator. Overall, tarsiers have well developed visual and auditory systems, and a less well developed somatosensory
system, suggesting an enhanced reliance on the visual and auditory senses, rather than somatosensory sense. 相似文献
2.
Five species of slow lorises were once considered to comprise a single strongly polymorphic species, Nycticebus coucang, ranging throughout South and Southeast Asia. The cryptic nature of these nocturnal primates has led to a lack of understanding
of their distribution patterns and abundance. In short surveys, often few if any lorises are detected, meaning that the few
available density estimates are from long-term studies. Based on new research in Sebangau National Park, Borneo, and compilation
of survey data from other areas, we provide the first comparative abundance estimates for all five slow loris species: N. coucang occurred in significantly higher abundances (median encounter rate 0.80/km: n = 15), than N. bengalensis (0.26/km; n = 12), or N. javanicus (0.11/km: n = 2), N. menagensis (0.02/km: n = 3), and N. pygmaeus (0.13/km: n = 4). Abundance estimates in Sebangau (0.19/km) did not increase with increasing survey effort, but for all species and studies
combined, study duration was positively correlated with abundance estimates. We did not find a relation between abundance
and body mass, nor between abundance and latitude. Long-term studies are more likely to be conducted at sites where the species
of interest is particularly plentiful. The data suggest that slow lorises occur at low abundances throughout much of their
range, and some in larger social groups than previously assumed. We recommend taking into account the species’ heterogeneous
distribution (potentially requiring larger survey effort), their social structure, the use of red lights as opposed to white
lights whilst surveying, and to make use of their vocalisations when surveying slow lorises. 相似文献
3.
Stefan Merker Christine Driller Irene Neri-Arboleda Hans Zischler 《Conservation Genetics》2008,9(5):1349-1351
This study reports the isolation and characterization of eight microsatellite markers for the study of Philippine tarsiers
(Tarsius syrichta), small primates endemic to this Southeast Asian archipelago. The markers were used to screen 14 Tarsius syrichta for allelic diversity. This suite of highly polymorphic microsatellites provides the first chance to genetically study parentage
and dispersal patterns in Philippine tarsiers. 相似文献
4.
The predation pressure put on primates by diurnal birds of prey differs greatly between continents. Africa and South America
have specialist raptors (e.g. crowned hawk-eagle Stephanoaetus coronatus and harpy eagle Harpia harpyja) whereas in Asia the only such specialist’s (Philippine eagle Pithecophaga jefferyi) distribution is largely allopatric with primates. The almost universal absence of polyspecific groups in Asia (common in
Africa and South America) may indicate reduced predation pressure. As such there is almost no information on predation pressures
on primates in Asia by raptors. Here we report successful predation of a juvenile banded langur Presbytis femoralis (~2 kg) by a changeable hawk-eagle Spizaetus cirrhatus. The troop that was attacked displayed no signs of being alarmed, and no calls were made before the event. We argue that
in insular Southeast Asia, especially, large Spizaetus hawk-eagles (~2 kg) are significant predators of arboreal colobines. Using data on the relative size of sympatric Spizaetus hawk-eagles and colobines we make predictions on where geographically we can expect the highest predation pressure (Thai–Malay
Peninsula) and which colobines are least (Nasalis larvatus, Trachypithecus auratus, P. thomasi) and most (P. femoralis, T. cristatus) affected. 相似文献
5.
Hiroyuki Motomura Carl D. Struthers Mark A. McGrouther Andrew L. Stewart 《Ichthyological Research》2011,58(4):315-332
The Scorpaena cardinalis complex, including S. cardinalis, S. jacksoniensis and S. orgila, is defined. The genus Ruboralga (type species: S. jacksoniensis) is regarded as a junior synonym of Scorpaena. Scorpaena jacksoniensis Steindachner 1866, previously treated as a junior synonym of Scorpaena cardinalis Solander and Richardson 1842, is regarded here as a valid species. Scorpaena cookii Günther 1874, previously treated as a valid species, is regarded here as a junior synonym of S. cardinalis. Thus, recent recognition of the two Australasian scorpionfishes, i.e., S. cardinalis and S. cookii, are re-identified in this study as S. jacksoniensis and S. cardinalis, respectively. Scorpaena plebeia Solander 1842 is regarded as a junior synonym of S. cardinalis. Scorpaena jacksoniensis is distributed along the east coast of Australia from southern Queensland to eastern Victoria, whereas S. cardinalis occurs around northern New Zealand, the Kermadec Islands and offshore islands of the Tasman Sea. A neotype is designated
for S. cardinalis. Morphological changes with growth in the two species are described in detail. 相似文献
6.
The cricetid species Democricetodon gracilis (Fahlbusch, 1964), Democricetodon mutilus (Fahlbusch, 1964), Megacricetodon bavaricus (Fahlbusch, 1964), and Megacricetodon minor (Lartet, 1851) from Sandelzhausen (Early/Middle Miocene boundary, MN5, Southern Germany) are represented by more than 2,000 molars providing
substantial data on the variability in sizes and on variation in morphologies. Temporal and spatial distributions of these
species indicate that they are probably immigrants in SE Germany, originating from south-eastern or more southern areas. Except
for M. minor, whose origin is not clear and could be regarded as an immigrant from more eastern areas. Using the length of the mesoloph
in the second upper molars as an indicator of habitat, D. gracilis and M. minor had a preference for a humid habitat, D. mutilus and M. bavaricus a preference for drier habitats.
相似文献
7.
Neolebouria blatta n. sp. is described from Pristipomoides argyrogrammicus (Valenciennes) and Etelis carbunculus Cuvier in waters off New Caledonia. It differs from all other species of Neolebouria Gibson, 1976 but one, N. georgenascimentoi Bray, 2002, in the extension of the cirrus-sac to the ovary or nearly so. It differs from N. georgenascimentoi in its continuous, rather than interrupted, vitelline distribution. N. blatta belongs to a small group of similar Neolebouria species reported in deep-water lutjanids, which includes N. longisacculus (Yamaguti, 1970) n. comb., N. rooseveltiae (Yamaguti, 1970) n. comb. and N. ulaula (Yamaguti, 1970). 相似文献
8.
In Arabidopsis, NPR1 (non-expressor of pathogenesis related genes 1, AtNPR1) functions downstream of salicylic acid (SA) and modulates the SA mediated systemic acquired resistance. It is also involved
in a cross talk with the jasmonate pathway that is essential for resistance against herbivores and necrotrophic pathogens.
Overexpression of AtNPR1 in transgenic plants resulted in enhanced disease resistance. Recently, tobacco transgenic plants expressing AtNPR1 were shown to be tolerant to the early instars of Spodoptera litura (Meur et al., Physiol Plant 133:765–775, 2008). In this communication, we show that the heterologous expression of AtNPR1 in tobacco has also enhanced the oxidative stress tolerance. The transgenic plants exhibited enhanced tolerance to the treatment
with methyl viologen. This tolerance was associated with the constitutive upregulation of PR1, PR2 (glucanase), PR5 (thaumatin like protein), ascorbate peroxidase (APX) and Cu2+/Zn2+ superoxide dismutase (SOD). This is the first demonstration of the novel function of heterologous expression of AtNPR1 in oxidative stress tolerance in transgenic tobacco. 相似文献
9.
B. Kozomara B. Vinterhalter Lj. Radojević D. Vinterhalter 《In vitro cellular & developmental biology. Plant》2008,44(2):142-147
A procedure for the micropropagation of Chimonanthus praecox (L) Link, wintersweet, has been developed using buds from adult trees excised in spring. Shoot cultures established on Murashige
and Skoog (1962) medium supplemented with 0.5 mg l−1 6-benzyladenine (BAP) and 0.1 mg l−1 indole-3-butyric acid (IBA) were difficult to maintain in vitro through extended periods of time due to browning of the medium, shoot and leaf necrosis, and hyperhydricity. A treatment
combining the use of 0.1% w/v activated charcoal and addition of a double phase agar-solidified/liquid medium improved propagation, enabling a successful
in vitro propagation scheme to be developed. Optimal shoot multiplication occurred on medium containing 0.5 mg l−1 BAP, and rooting on medium with 2.0 mg l−1 IBA for 7 d, followed by transfer to hormone-free medium. Rooted plantlets were easily acclimated in a glasshouse and replanted
and cultured outdoors. 相似文献
10.
Elizabeth C. White Jean-Thoussaint Dikangadissi Edmond Dimoto William B. Karesh Michael D. Kock Nathacha Ona Abiaga Ruth Starkey Tharcisse Ukizintambara Lee J. T. White Katharine A. Abernethy 《International journal of primatology》2010,31(4):627-645
The predicted relationship between home-range size and group mass in primates developed by Clutton-Brock and Harvey (1977) has proved extremely robust in describing the use of space by most primate species. However, mandrills (Mandrillus sphinx) are now known to have an extreme group mass in the wild, far larger than that of the species used originally to generate
that relationship, and so it was unknown whether this relationship would be robust for this species. We investigated the home-range
size and use of a wild horde of ca. 700 mandrills in Lopé National Park, Gabon, using radiotelemetry. The total area the horde used over a 6-yr period [100%
minimum convex polygon (MCP)] was 182 km2, including 89 km2 of suitable forest habitat. Mandrills used gallery forests and isolated forest fragments with high botanical diversity far
more intensively that the continuous forest and completely avoided savanna and marsh. Peeled polygons and fixed kernel contours
revealed multiple centres of use, with the horde spending more than half its time in <10% of the total documented range, typical
of a frugivore using a patchy environment. Home-range size and internal structure varied considerably between years, but total
home range fitted the predicted relationship between group mass and home range size, despite being an outlier to the dataset.
We discuss the conservation implications of the species’ space requirements, in light of current pressures on land use in
their range. 相似文献
11.
Yaser Hassan Dewir Nisha Singh Shakira Shaik Ashley Nicholas 《In vitro cellular & developmental biology. Plant》2010,46(1):41-46
The present study reports a simple protocol for indirect shoot organogenesis and plant regeneration of Sutherlandia using rachis and stem segments. Different concentrations (0.0–68.08 μmol l−1) of thidiazuron (TDZ) were used for callus induction and shoot organogenesis. The highest percentage of callus formation
(97.5%) and the highest percentage of explants forming shoots (88.8%) were obtained from rachis explants cultured onto Murashige
and Skoog (MS) medium (Murashige and Skoog, Physiol. Plant. 15:473–495, 1962) supplemented with 45.41 μmol l−1 TDZ. Scanning electron microscopy demonstrated the early development of adventitious shoots derived from callus cultures.
Shoot clusters were further developed and grown in MS hormone-free medium. The presence of l-canavanine was determined by thin-layer chromatography and confirmed after column fractionation using silica gel and nuclear
magnetic resonance spectroscopy. Individual shoots were rooted on different concentrations and combinations of MS salt strength
and IBA. Half-strength MS salt medium supplemented with 24.6 μmol l−1 IBA was optimal for root induction in which 78% of shoots were rooted. The in vitro plants were successfully acclimatized in a growth chamber with a 90% survival rate. 相似文献
12.
A genetic transformation system has been developed for callus cells of Crataegus
aronia using Agrobacterium
tumefaciens. Callus culture was established from internodal stem segments incubated on Murashige and Skoog (MS) medium supplemented with
5 mg l−1 Indole-3-butyric acid (IBA) and 0.5 mg l−1 6-benzyladenine (BA). In order to optimize the callus culture system with respect to callus growth and coloration, different
types and concentrations of plant growth regulators were tested. Results indicated that the best average fresh weight of red
colored callus was obtained on MS medium supplemented with 2 mg l−1 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.5 mg l−1 kinetin (Kin) (callus maintenance medium). Callus cells were co-cultivated with Agrobacterium harboring the binary plasmid pCAMBIA1302 carrying the mgfp5 and hygromycin phosphotransferase (hptII) genes conferring green fluorescent protein (GFP) activity and hygromycin resistance, respectively. Putative transgenic calli
were obtained 4 weeks after incubation of the co-cultivated explants onto maintenance medium supplemented with 50 mg l−1 hygromycin. Molecular analysis confirmed the integration of the transgenes in transformed callus. To our knowledge, this
is the first time to report an Agrobacterium-mediated transformation system in Crataegus
aronia. 相似文献
13.
Junko Kitagawa Takeshi Nakagawa Masaaki Okuda Masaharu Fukuoka Yoshinori Yasuda 《Economic botany》2008,62(4):594-603
Correcting Misperceptions about the History of
Castanea
Stands in
Satoyama
in Japan. Mistaken ideas about the naturalness of past and present landscapes are widespread in diverse cultures and in the scientific
literature, and many of these ideas are only now being seriously challenged by current research (e.g., Erickson 2006; Fairhead and Leach 1996; Hall 1998; Ramankutty and Foley 1999; Willis et al. 2004). For example, the chestnut, Castanea crenata, has long been an important tree in Japanese culture, which has been cultivated, among other things, for its much loved edible
nut and its valuable timber. Today, the widely-held view in Japan, which also appears in the scholarly and popular literature,
is that in the past Castanea stands covered a large area throughout Japan, and these stands only disappeared because of economic development, especially
in association with railway construction. Otaru, Hokkaido, is one of the places where people believe Castanea stands covered a large area and were deforested only recently. Local people in Otaru believe that the stand in Temiya Park
has existed since the Jomon Period. For a more accurate historical perspective on Japanese forestation, we have performed
pollen analysis to clarify the timing of the introduction of the Castanea tree into Otaru region and to reveal the history of this specific Castanea stand in Temiya Park. The results indicate that Castanea was first found in Otaru region 7100 B.P., but that it was not cultivated extensively until recently. Based on our study,
and on data from this area dating to the late 19th century, we concluded instead that the Castanea stand we studied in Temiya Park, Otaru, was established after the mid-20th century. We believe the results of this study
are applicable to Castanea stands in other parts of Japan as well. 相似文献
14.
Karen A. Silverman Revati A. Koratkar Linda D. Siracusa Arthur M. Buchberg 《Mammalian genome》2003,14(2):119-129
Abstract
We recently identified the Modifier of Min 2 (Mom2) locus. Mom2 is a new modifier of intestinal tumorigenesis that resulted from a spontaneous mutation in a B6 Apc
Min/+ mouse. The presence of one resistant Mom2
R allele results in a significant reduction in small intestinal polyp number and colon polyp incidence in Apc
Min/+ mice. Through linkage analysis, we previously localized Mom2 to a 14-cM region on mouse Chromosome (Chr) 18, distal to the Apc gene. This region is syntenic with human Chr 18q, which frequently undergoes loss of heterozygosity (LOH) in several human cancers, including colorectal cancer. Residing in this region are the Madh2 and Madh4 genes, which have both been implicated in human colorectal cancer. Based on meiotic recombinations within the Mom2 region in the derivation of our congenic animals, we have narrowed the location of the Mom2 locus and excluded Madh2, Madh4, and Madh7, as well as Mbd1, Mbd2, Dcc, and Tcf4, as candidates for the Mom2 gene. 相似文献
15.
Control of livestock diseases can become complicated when wild animals are involved. The Eurasian badger (Meles meles) is considered the principle wildlife host of Mycobacterium bovis (which causes bovine tuberculosis, bTB) in Great Britain and Ireland, but wild deer have also been implicated. Whether wild
deer are likely to perpetuate bTB in cattle depends on the exposure risks they pose, the mode of pathogen transmission, the
distances over which the disease can be transported and whether they can maintain infection within their own populations independently
of other sources. We evaluated the likely host status of each of four species of wild British deer (red, roe, fallow and Reeves'
muntjac) and the badger across a range of densities typically observed in Britain by manipulating the reproductive number
equation proposed by Anderson and May (1991). We estimate that roe deer almost certainly act as spillover hosts at densities lower than 30 km−2, red deer below 16 km−2, muntjac below 6 km−2, fallow below 4 km−2 and the badger below 2 km−2. We also estimate that muntjac will almost certainly act as maintenance hosts at densities above 56 km−2, fallow above 47 km−2 and badgers above 24 km−2. For densities between these values, we cannot be certain of the host status of these species, and for red and roe deer we
cannot be certain of host status under most natural conditions typically experienced in parts of Britain experiencing high
incidence of bTB in cattle. However, enhanced transmission rates resulting from artificially high densities such as might
be experienced at supplementary feeding sites may be sufficient to promote independent maintenance of infection. We were not
able to confidently assign host status to any species over a wide range of densities, but conclude that this is likely to
reflect reality, where host status may be affected as much by, for example, demographic fluctuations as it is by population
density. Our results imply densities below which populations of wild deer inhabiting cattle bTB hotspots ought to be maintained
in order to control the possibility of them perpetuating the cycle of intra- and interspecific M. bovis transmission. 相似文献
16.
Dussle CM Hahn V Knapp SJ Bauer E 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2004,109(5):1083-1086
The Pl
Arg
locus in the sunflower (Helianthus annuus L.) inbred line Arg1575-2 conferring resistance to at least four tested races (300, 700, 730, 770) of downy mildew (Plasmopara halstedii) was localized by the use of simple sequence repeat (SSR) markers. Bulked segregant analysis (BSA) was conducted on 126 individuals of an F2 progeny from a cross between a downy mildew susceptible line, CmsHA342, and Arg1575-2. Twelve SSR markers linked to the Pl
Arg
locus were identified. All markers were located proximal to Pl
Arg
on linkage group LG1 based on the map of Yu et al. (2003) in a window of 9.3 cM. Since Pl
Arg
was mapped to a linkage group different from all other Pl genes previously mapped with SSRs, it can be concluded that Pl
Arg
provides a new source of resistance against P. halstedii in sunflower. 相似文献
17.
18.
Bryant D 《Bulletin of mathematical biology》2009,71(2):339-351
The Hadamard transform (Hendy and Penny, Syst. Zool. 38(4):297–309, 1989; Hendy, Syst. Zool. 38(4):310–321, 1989) provides a way to work with stochastic models for sequence evolution without having to deal with the complications of tree
space and the graphical structure of trees. Here we demonstrate that the transform can be expressed in terms of the familiar
P[τ]=e
Q[τ] formula for Markov chains. The key idea is to study the evolution of vectors of states, one vector entry for each taxa; we
call this the n-taxon process. We derive transition probabilities for the process. Significantly, the findings show that tree-based models
are indeed in the family of (multi-variate) exponential distributions. 相似文献
19.
Recently, the prenyltransferase SirD was found to be responsible for the O-prenylation of tyrosine in the biosynthesis of sirodesmin PL in Leptosphaeria maculans. In this study, the behavior of SirD towards phenylalanine/tyrosine and tryptophan derivatives was investigated. Product
formation has been observed with 12 of 19 phenylalanine/tyrosine derivatives. It was shown that the alanine structure attached
to the benzene ring and an electron donor, e.g., OH or NH2, at its para-position are essential for the enzyme activity. Modifications were possible both at the side chain and the benzene ring.
Enzyme products from seven phenylalanine/tyrosine derivatives were isolated and characterized by MS and NMR analyses including
HSQC and HMBC and proven to be O- or N-prenylated derivatives at position C4 of the benzene rings. K
M
values of six selected derivatives were found in the range of 0.10–0.68 mM. Catalytic efficiencies (K
cat/K
M
) were determined in the range of 430–1,110 s−1·M−1 with l-tyrosine as the best substrate. In addition, 7 of 14 tested tryptophan analogs were also accepted by SirD and converted to
C7-prenylated derivatives, which was confirmed by comparison with products obtained from enzyme assays using a 7-dimethylallyltryptophan
synthase 7-DMATS from Aspergillus fumigatus. 相似文献
20.
Aneta Kostadinova 《Systematic parasitology》2009,73(2):141-150
Sarabeev & Balbuena (2003) considered Dicrogaster perpusilla Looss, 1902 and D. contracta Looss, 1902 (Digenea: Haploporidae) synonymous. They designated a neotype for the type-species, D. perpusilla, from a sample of specimens ex Chelon labrosus off West Thurrock, UK. The morphology of the material (three specimen lots) studied by these authors was re-examined in detail
and compared with their data. The material labelled ‘D. perpusilla’ from off West Thurrock, from which the neotype specimen was selected, consists of 14 specimens; of these one might belong
to Haploporus Looss, 1902 and one to Haplosplanchnus Looss 1902. A well-developed genital atrium was observed in 11 of the 12 remaining specimens, and they all possess large
saccular caeca and a vitellarium consisting of two groups of loosely coalesced follicles rather than two compact masses. These
features suggest that the 12 specimens of this lot may belong to Saccocoelium Looss, 1902, but the state of the material does not permit its reliable identification. The specimen designated by Sarabeev
& Balbuena (2003) as the neotype of D. perpusilla represents a neogravid dorso-laterally mounted specimen and is unrecognisable. Although five of the six voucher specimens
of these authors may represent Dicrogaster spp., the poor state of this material does not allow its accurate identification. The metrical data obtained from this voucher
material indicate that juvenile and laterally mounted specimens have been used in the comparisons upon which the synonymy
of D. perpusilla and D. contracta was suggested. The overall conclusion of the study is that the synonymy of D. contracta and D.
perpusilla proposed by Sarabeev & Balbuena (2003) is based on questionable material. Since the neotype of D. perpusilla is unrecognisable, and a number of qualifying conditions of the ICZN in its designation were not met, the usage of the original
conception of the type-species of Dicrogaster given by Looss (1902) is recommended. 相似文献