The interaction between plants and frugivores plays a critical role in sustaining ecosystem function and community diversity, but little is known about the structure of interaction networks between fruit plants and frugivore birds in urban green spaces. We observed the interactions between plants and birds throughout the year in the Guilin Botanical Garden and assessed the characteristics of the total plant-frugivore and seasonal networks. We also analyzed the relationship between the network roles of species and ecological traits to explore the structure and characteristics of the plant-frugivore network. The interactions between a total of 14 frugivore birds and 13 fruit plant species were analyzed in the study area, the autumn and winter interaction connections contributed 38.79% and 33.15% to the total network, respectively. The specialization (H2´), and interaction evenness (E2) of the network were higher in spring and summer than that in autumn and winter. However, connectance (C), nestedness, and interaction diversity (H2) were contrary to the specialization and interaction evenness of the network. Compared to the networks (N=1000) generated by the null model, the observed network exhibited lower connectance (C), interaction diversity(H2), interaction evenness (E2), and higher nestedness and specialization (H2´). A correlation analysis combining ecological traits and network roles showed that plants with black fruit had higher species strength, whereas the other traits of plants and birds were not significantly correlated with their network parameters.

Play behavior is a significant trait of immature nonhuman primates (hereafter primates), which may play important roles in sensory, locomotor, socio-cognitive, and developmental processes in primates. It has been suggested that function of play is to practice and improve motor skills related to foraging, avoiding predation, attracting mates, raising offspring, and also is to strength social skills concerning to cementing friendly relationships and defraying aggression among individuals. From September 2009 to August 2010, we investigated play behaviors of 1-12-month-old white-headed langur (Trachypithecus leucocephalus) which is a critically endangered primate endemic to China. During this study, we recorded 4,421 play bouts and 1,302 minutes of play time of 7 infants in total. We found that infants had different play behavior patterns at different ages. Specifically, non-social play behaviors appeared at 1 month of age, social play behaviors at 2 months, and all types of social and non-social play behaviors at 3 months. The frequency and duration of non-social play peaked at 5 months and then decreased, while social play appeared at 2 months and gradually increased with age. Non-social play did not differ between the sexes, whereas social play showed sex specificity, with higher frequency and duration of social play in male infants than in female infants. In addition, male and female white-headed langur infants appeared to prefer the individuals of same sex as social playmates. In conclusion, we first reported the pattern of play behavior of a critically endangered langur aged 1 to 12 months though the sample size is small, our results suggest they may have the adaptation of play behaviors in ages and sexes, which may help them adapt to their habitat and social system.