We identified the significant spatial relationships between tree species mingling and size inequality in various species-rich natural forests South China. Forest communities with low mingling, or segregation of heterospecific trees, exhibited increased trees dissimilar sizes. Large were more likely to be associated high variation neighboring sizes would also increase neighborhood diversity. Num...

Hyperparasitism is a normal behavior of parasitoids, which often happens among species. Conspecific hyperparasitism, such as some kinds of heteronomous hyperparasitic behaviors, has been only reported in some species belonging to Aphelinidae. In this article, the conspecific hyperparasitism of Pachycrepoideus vindemmiae (Pteromalidae) is reported, with Drosophila puparia as hosts. Hosts were ex...

Male sailfin mollies Poecilia latipinna were tested in five different treatments that varied in the relative frequency of heterospecific gynogens (Amazon molly Poecilia formosa) to conspecific females to determine whether social interactions among males within a population causes some males to mate with heterospecific females. Male P. latipinna inseminated a significantly higher proportion of c...

Dopamine (DA) neurons increase and decrease firing for rewards that are better and worse than expected, respectively. These correlates have been observed at the level of single-unit firing and in measurements of phasic DA release in ventral striatum (VS). Here, we ask whether DA release is modulated by delivery of reward, not to oneself, but to a conspecific. It is unknown what, if anything, DA...

For many species of long-lived organisms, such as trees, survival appears to be the most critical vital rate affecting population persistence. However, methods commonly used to quantify tree death, such as relating tree mortality risk solely to diameter growth, almost certainly do not account for important spatial processes. Our goal in this study was to detect and, if present, to quantify the ...

We investigated seed dispersal and density-dependence of seed, seedling and sapling survival in two BCI tree species of contrasting life history strategies, using data from seed traps, soil seed samples, seedling plots within the forest dynamics plot, and the plot census data themselves. Seed dispersal distances and seed production per unit basal area were significantly higher in Miconia argent...

Organisms often perceive predation risk through visual, auditory, or chemical cues that accompany or persist after an attack on other prey individuals. In this paper an argument is developed that suggests that it is adaptive for species that use such indirect cues to include conspecific density in the assessment of predation risk, and to respond to conspecific density by modifying phenotype (e....

Conspecific sperm precedence occurs when females are exposed to sperm from males of multiple species, but preferentially use sperm of a conspecific. Conspecific sperm precedence and its mechanisms have been documented widely in terrestrial species, in which complex female behaviors or reproductive tract morphologies can allow many opportunities for female choice and sperm competition, however, ...

Socially isolated Macropodus opercularis showed a distinct approach response to water taken from the tank of a conspecific individual or a nonconspecific, Trichogaster trichopterus, but not to water from a tank without fish. It is proposed that these species produce chemical stimuli which are attractive to M. opercularis. Approach frequency and the total duration of approach during a 10-rain pe...

Harsh environmental conditions in arid ecosystems limit seedling recruitment to microhabitats under nurse structures, such as shrubs or rocks. These structures, however, do not necessarily afford the same benefits to plants because nurse rocks provide only physical nurse effects, whereas nurse plants can provide both physical and biological nurse effects. Nevertheless, if the nurse plant is a c...