Age Differences in Behavioral Responses of Male Giant Pandas to Chemosensory Stimulation

Chemical communication plays an important role in survival and reproductive success in mammalian species. In the present study, we examined the ontogenetic pattern of behavioral responses of male giant pandas （Ailuropoda melanoleuca ） to urine odors of conspecific individuals. Our data showed that exposure to the urine of adult females induced a significant increase in sniffing and environmental sniffing/licking behaviors, but a decrease in biting behavior, in males. Males of different ages displayed specific behaviors to female urine odors. Adult males spent more time licking than juvenile and sub-adult males. Further, sub-adult and adult males displayed high levels of environmental sniffing/licking, which was absent in the juvenile males. Juvenile males displayed scent rubbing behavior significantly more frequently than sub-adult and adult males, and also spent more time showing biting behavior than sub-adult males. Finally, juvenile and sub-aduh males showed no difference in response to female and male urine odors. Together, these data suggest that chemosensory cues from conspecific urines induce age-specific responses in male giant pandas.

FRACTAL BEHAVIOR OF DEVELOPMENT OF PHASE SEPARATION AND CRYSTALLIZATION IN BLENDS OF NYLON-6 WITH SODIUM SALT OF ETHYLENE /METHACRYLIC ACID COPOLYMER

Phase separation was studied by the optical microscopy in blends of nylon 6 (PA6) with sodium salt of ethylene/methacrylic acid copolymer (PEMA).The image collecting technology was used to keep track of the development of blends at a certain temperature.The fractal dimension of phase separation was calculated by the image solving technology according to the fractal theory and the self similarity behavior of the process was proved.The relationship of the fractal behavior with composition and experimental temperature was discussed.The fractal behavior of the crystallization development of the crystal phase of PA6 in blends was also discussed and the fractal behavior calculated.

Cropland physical disturbance intensity： plot-scale measurement and its application for soil erosion reduction in mountainous areas

Various kinds of human disturbances on cropland are the main reasons for soil erosion and land degradation.Farming practices in mountainous areas vary greatly among cropland plots because of the heterogeneity of biophysical conditions and differences in farmers'management behavior.The main purpose of this paper is to develop a composite index of cropland physical disturbance intensity(CLDI)to reflect the plot-scale discrepancy of potential soil erosion in mountainous areas.The study was based on both plot survey and household interview data,collected from six typical catchments in mountainous areas of southwestern China.Four kinds of physical disturbance practices and two kinds of conservation practices during one crop rotation period were synthesized to develop the CLDI index.The rough set theory was referenced to avoid subjectivity during weight allocation.The results show that conventional tillage,deep fertilization,and manual weeding are the main causes of cropland soil erosion,whereas manure application in combination with seasonal fallow reduces soil erosion.Different crop types as well as cropland location factors determine the spatial pattern of CLDI.Crop rotation modes with major crops of tobacco and maize resulted in a maximal CLDI,and cropland plots with a distance radius of 150 meters away from households received the most intensive physical disturbance.These results are critical to help better protect rural environments in mountainous areas.Based on the results,methods to reduce cropland soil erosion are suggested.

Methoprene does not affect juvenile hormone titers in honey bee （Apis mellifera） workers

Methoprene, a juvenile hormone （JH） analog, is a widely used insecticide that also accelerates behavioral development in honey bees （Apis mellifera）. JH regulates the transition from nursing to foraging in adult worker bees, and treatment with JH or methoprene have both been shown to induce precocious foraging. To determine how methoprene changes honey bee behavior, we compared JH titers ofmethoprene-treated and untreated bees. Behavioral observations confirmed that methoprene treatment significantly increased the number of precocious foragers in 3 out of 4 colonies. In only 1 out of 4 colonies, however, was there a significant difference in JH titers between the methoprene- treated and control bees. Further, in all 4 colonies, there was no significant differences in JH titers between precocious and normal-aged foragers. These results suggest that methoprene did not directly affect the endogenous JH secreted by corpora allata. Because methoprene caused early foraging without changing workers＇ JH titers, we conclude that methoprene most likely acts directly on the JH receptors as a substitute for JH.

Call it sleep-what animals without backbones can tell us about the phylogeny of intrinsically generated neuromotor rhythms during early development

A comprehensive overview is presented of the literature dealing with the development of sleep-like motility and neuronal activity patterns in non-vertebrate animals. It has been established that spontaneous, periodically modulated, neurogenic bursts of movement appear to be a universal feature of prenatal behavior. New empirical data are presented showing that such ＇seismic sleep＇ or ＇rapid-body-movement＇ bursts in cuttlefish persist for some time after birth. Extensive ontogenetic research in both vertebrates and non-vertebrates is thus essential before current hypotheses about the phylogeny of motorically active sleep-like states can be taken seriously.

Interactions of sex and early life social experiences at two developmental stages shape nonapeptide receptor profiles

Early life social experiences are critical to behavioral and cognitive development,and can have a tremendous influence on developing social phenotypes.Most work has focused on outcomes of experiences at a single stage of development(e.g.perinatal or post-weaning).Few studies have assessed the impact of social experience at multiple developmental stages and across sex.Oxytocin and vasopressin are profoundly important for modulating social behavior and these nonapeptide systems are highly sensitive to developmental social experience,particularly in brain areas important for social behavior.We investigated whether oxytocin receptor(OTR)and vasopressin receptor(V1aR)distributions of prairie voles(Microtus ochrogaster)change as a function of parental composition within the natal nest or social composition after weaning.We raised pups either in the presence or absence of their fathers.At weaning,offspring were housed either individually or with a same-sex sibling.We also examined whether changes in receptor distributions are sexually dimorphic because the impact of the developmental environment on the nonapeptide system could be sex-dependent.We found that differences in nonapeptide receptor expression were region-specific,sex-specific and rearing condition-specific,indicating a high level of complexity in the ways that early life experiences shape the social brain.We found many more differences in V1aR density compared to OTR density,indicating that nonapeptide receptors demonstrate differential levels of neural plasticity and sensitivity to environmental and biological variables.Our data highlight that critical factors including biological sex and multiple experiences across the developmental continuum interact in complex ways to shape the social brain.