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981.
The influence of parasitoids and soil compaction on pupation behavior of blow flies was examined in a host–parasitoid system involving Lucilia sericata (Meigen) (Diptera: Calliphoridae) and Nasonia vitripennis (Walker) (Hymenoptera: Pteromalidae). Larvae of L. sericata were introduced to containers with soil of different compaction levels, with or without parasitoids. Although females of N. vitripennis did not significantly affect the pupation depth of L. sericata, they increased the rate of pupal development by 15.0–23.7 h at 28.4 ± 1.2 °C, and increased the clumping of puparia. Pupation depth of L. sericata was negatively related to soil compaction; mean depth of pupation was 4.4 cm in uncompacted soil and 0.5 cm in high‐compaction soil. In high‐compaction soil, pupal development increased by 10.5–18.8 h at 25.2 ± 0.3 °C, and puparia were clumped. These results provide a framework for locating puparia in forensic investigations and releasing appropriate parasitoids for biological control of blow flies.  相似文献   
982.
Scent-marking behavior is associated with different behavioral contexts in callitrichids, including signalizing a territory, location of feeding resources, and social rank. In marmosets and tamarins it is also associated with intersexual communication. Though it appears very important for the daily routine of the individuals, very few researchers have investigated distribution through the 24-h cycle. In a preliminary report, we described a preferential incidence of this behavior 2 h before nocturnal rest in families of common marmosets. We expand the data using 8 family groups (28 subjects), 8 fathers, 6 mothers, 8 nonreproductive adults (4 sons and 4 daughters), and 6 juvenile (3 sons and 3 daughters) offspring that we kept in outdoor cages under natural environmental conditions. We recorded the frequency of anogenital scent marking for each group during the light phase, twice a wk, for 4 consecutive wks, from March 1998 to September 1999. Cosinor test detected 24- and 8-h variations in 89.3% and 85.7% of the subjects, respectively, regardless of sex or reproductive status. The 8-h component is a consequence of the 2 peaks for the behavior, at the beginning and end of the light phase. Daily distribution of scent marking is similar to that others described previously for motor activity in marmosets. The coincident rhythmical patterns for both behaviors seem to be associated with feeding behavior, as described for callitrichids in free-ranging conditions, involving an increase in foraging activities early in the morning and shortly before nocturnal rest.  相似文献   
983.
Bearded sakis are seed predators, but are also known to consume arthropods. This is the first detailed report of arthropod predation in southern bearded sakis (Chiropotes satanas). Two groups were monitored-one in continuous forest, and one on a small island-between January 2003 and February 2004. The arthropod prey included spiders and six insect orders. Island group members spent more time foraging for arthropods (3.8% vs. 2.6% of activity time) but ingested less prey (3.7% vs. 4.6% of feeding time). Arthropods accounted for a small proportion of feeding records in most months, but there were occasional sharp peaks due to the exploitation of temporary agglomerations of insects. In November, arthropods accounted for 26.6% and 14.2% of the feeding records of the mainland and island groups, respectively. The results suggest that bearded sakis actively seek arthropods as a dietary supplement, but that they represent a minor resource during most of the year, even under conditions of intense habitat fragmentation (island group).  相似文献   
984.
E. L. Sumina 《Microbiology》2006,75(4):459-464
The observations of a laboratory culture of filamentous cyanobacteria revealed a complex of behavioral responses of their community, which maintain their activity as an integrated entity. A number of structures formed in the course of filament regrouping were revealed and described; their possible structural and functional analogues in eukaryotic organisms were determined. It is assumed that the behavioral reactions of the filaments help to maintain the integrity of the community at the stage prior to the formation of the structural bonds between its elements.  相似文献   
985.
Unusual behaviours not normally seen in the wild were studied in 52 captive agile (Hylobates agilis albibarbis) and 23 Müllers gibbons (H. muelleri spp) at three locations within the Kalaweit Gibbon Rehabilitation Project. Unusual behaviours included stereotypic behaviour (SB), human-directed masturbation and posterior presenting. These data were collected over 18 months as part of an ongoing study into behavioural adaptation of gibbons in a rehabilitation programme. Data were also collected on the unusual behaviours observed, for example, SB, human-directed masturbation and posterior presenting. I suggest causes of the abnormal behaviours and propose solutions to reduce their incidence in order to improve the gibbon’s progress in rehabilitation. From this study I conclude that most gibbons can be rehabilitated from the point of view of acquiring and maintaining a normal behavioural repertoire once in suitable housing. Encouraging the gibbons to reduce and/or stop these unusual behaviours is key to the welfare of the gibbons while in the rehabilitation programme and to successful release into a forest habitat. An erratum to this article can be found at  相似文献   
986.
We combine structural limb data and behavioral data for free-ranging chimpanzees from Ta? (Ivory Coast) and Mahale National Parks (Tanzania) to begin to consider the relationship between individual variation in locomotor activity and morphology. Femoral and humeral cross sections of ten individuals were acquired via computed tomography. Locomotor profiles of seven individuals were constructed from 3387 instantaneous time-point observations (87.4 hours). Within the limited number of suitable chimpanzees, individual variation in locomotor profiles displayed neither clear nor consistent trends with diaphyseal cross-sectional shapes. The percentages of specific locomotor modes did not relate well to diaphyseal shapes since neither infrequent nor frequent locomotor modes varied consistently with shapes. The percentage of arboreal locomotion, rather than estimated body mass, apparently had comparatively greater biological relevance to variation in diaphyseal shape. The mechanical consequences of locomotor modes on femoral and humeral diaphyseal shapes (e.g., orientation of bending strains) may overlap between naturalistic modes more than currently is recognized. Alternatively, diaphyseal shape may be unresponsive to mechanical demands of these specific locomotor modes. More data are needed in order to discern between these possibilities. Increasing the sample to include additional free-ranging chimpanzees, or primates in general, as well as devoting more attention to the mechanics of a greater variety of naturalistic locomotor modes would be fruitful to understanding the behavioral basis of diaphyseal shapes.  相似文献   
987.
Optically stimulated luminescence (OSL) measurements are reported for both single aliquots (of two different sizes) and single grains of quartz from deposits within Blombos Cave. Ages have been obtained for six sediments from the Middle Stone Age (MSA) occupation levels and for two sterile sands, one underlying the archaeological sediment and one overlying the Later Stone Age occupation levels. The ages for the archaeological sediments were obtained from single-grain measurements that enabled unrepresentative grains to be rejected. The MSA occupation levels have ages that, within error limits, are in stratigraphic order and fall between the OSL age for the oldest dune sand (143.2+/-5.5 ka) and a previously published OSL age for the sterile sand ( approximately 70 ka) that separates the Middle and Later Stone Age deposits. The earliest MSA archaeological phase, M3, from where fragments of ochre were found as well as human teeth, is dated to 98.9+/-4.5 ka, coinciding with the sea-level high of oxygen isotope substage 5c. The cave then appears to be unoccupied until oxygen isotope substage 5a on the basis of four OSL ages for archaeological phase M2, ranging from 84.6+/-5.8 to 76.8+/-3.1 ka; these levels contained large hearths and bone tools. An age of 72.7+/-3.1 ka was obtained for the final MSA archaeological phase, M1, from which deliberately engraved ochre and shell beads were recovered along with bifacial stone points. We conclude that the periods of occupation were determined by changes in sea level, with abundant sources of seafood available in times of high sea level and with the cave being closed by the accumulation of large dunes during periods of low sea level, such as during oxygen isotope stages 4 and 6.  相似文献   
988.
During early stages of brain development, neuroepithelial stem cells undergo intense proliferation as neurogenesis begins. Fibroblast growth factor 2 (FGF2) has been involved in the regulation of these processes, and although it has been suggested that they work in an autocrine-paracrine mode, there is no general agreement on this because the behavior of neuroepithelial cells is not self-sufficient in explants cultured in vitro. In this work, we show that during early stages of development in chick embryos there is another source of FGF2, besides that of the neuroepithelium, which affects the brain primordium, since the cerebrospinal fluid (E-CSF) contains several isoforms of this factor. We also demonstrate, both in vitro and in vivo, that the FGF2 from the E-CSF has an effect on the regulation of neuroepithelial cell behavior, including cell proliferation and neurogenesis. In order to clarify putative sources of FGF2 in embryonic tissues, we detected by in situ hybridization high levels of mRNA expression in notochord, mesonephros and hepatic primordia, and low levels in brain neuroectoderm, corroborated by semiquantitative PCR analysis. Furthermore, we show that the notochord segregates several FGF2 isoforms which modify the behavior of the neuroepithelial cells in vitro. In addition, we show that the FGF2 ligand is present in the embryonic serum; and, by means of labeled FGF2, we prove that this factor passes via the neuroepithelium from the embryonic serum to the E-CSF in vivo. Considering all these results, we propose that, in chick embryos, the behavior of brain neuroepithelial stem cells at the earliest stages of development is influenced by the action of the FGF2 contained within the E-CSF which could have an extraneural origin, thus suggesting a new and complementary way of regulating brain development.  相似文献   
989.
Spider venom sphingomyelinases D catalyze the hydrolysis of sphingomyelin via an Mg(2+) ion-dependent acid-base catalytic mechanism which involves two histidines. In the crystal structure of the sulfate free enzyme determined at 1.85A resolution, the metal ion is tetrahedrally coordinated instead of the trigonal-bipyramidal coordination observed in the sulfate bound form. The observed hyperpolarized state of His47 requires a revision of the previously suggested catalytic mechanism. Molecular modeling indicates that the fundamental structural features important for catalysis are fully conserved in both classes of SMases D and that the Class II SMases D contain an additional intra-chain disulphide bridge (Cys53-Cys201). Structural analysis suggests that the highly homologous enzyme from Loxosceles bonetti is unable to hydrolyze sphingomyelin due to the 95Gly-->Asn and 134Pro-->Glu mutations that modify the local charge and hydrophobicity of the interfacial face. Structural and sequence comparisons confirm the evolutionary relationship between sphingomyelinases D and the glicerophosphodiester phosphoesterases which utilize a similar catalytic mechanism.  相似文献   
990.
The physiological mechanisms of parental and alloparental care in cooperatively breeding nonhuman primate species such as the common marmoset (Callithrix jacchus) are poorly known. In this study, we examined prolactin and cortisol plasma levels of fathers and older offspring of both sexes, with and without previous experience in infant carrying, around parturition and during infant carrying. Blood samples were collected from fathers and older offspring and prolactin and cortisol were measured by RIA and EIA, respectively. Prolactin levels of both caretakers were not influenced by infant's birth, previous experience or proximity to parturition. However, prolactin levels increased in both caretakers while in physical contact with infants and also with the number of infants being carried in older offspring. These findings suggest that increased prolactin seems to be mainly due to physical effort rather than a physiological trigger of paternal and alloparental care in common marmosets. Cortisol levels were higher for experienced fathers shortly before parturition which could act to reinforce affiliative bonds between breeding males and females at this time or in the ability of males to detect the proximity of the parturition or both.  相似文献   
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