Perception of artificial conspecifics by bearded dragons(Pogona vitticeps)

Artificial animals are increasingly used as conspecific stimuli in animal behavior research.However,research­ers often have an incomplete understanding of how the species under study perceives conspecifics,and,hence,which features are needed for a stimulus to be perceived appropriately.To investigate the features that bearded dragons(Pogona vitticeps)attend to,we measured their lateralized eye use when assessing a successive range of stimuli.These ranged through several stages of realism in artificial conspecifics,to see how features such as color,the presence of eyes,body shape and motion influence behavior.We found differences in lateralized eye use depending on the sex of the observing bearded dragon and the artificial conspecific,as well as the artificial conspecific’s behavior.Therefore,this approach can inform the design of robotic animals that elicit biological­ly-meaningful responses in live animals.

Root overlap and allocation of above- and belowground growth of European beech in pure and mixed stands of Douglas fir and Norway spruce

Site conditions and species identity have a combined effect on fine root growth of trees in pure and mixed stands.However,mechanisms that may contribute to this effect are rarely studied,even though they are essential to assess the potential of species to cope with climate change.This study examined fine root overlap and the linkage between fine root and stem growth of European beech(Fagus sylvatica)growing in pure and mixed stands with Douglas fir(Pseudotsuga menziesii)or Norway spruce(Picea abies)at two different study sites in northwestern Germany.The study sites represented substantially different soil and climate conditions.At each site,three stands,and at each stand,three pairs of trees were studied.In the pure beech stand,the pairs consisted of two beech trees,while in the mixed stands each pair was composed of a beech tree and a conifer.Between each pair,three evenly spaced soil cores were taken monthly throughout the growing season.In the pure beech stands,microsatellite markers were used to assign the fine roots to individual trees.Changes in stem diameter of beech were quantified and then upscaled to aboveground wood productivity with automatic high-resolution circumference dendrometers.We found that fine root overlap between neighboring trees varied independently of the distance between the paired trees or the stand types(pure versus mixed stands),indicating that there was no territorial competition.Aboveground wood productivity(wood NPP)and fine root productivity(root NPP)showed similar unimodal seasonal patterns,peaking in June.However,this pattern was more distinct for root NPP,and root NPP started earlier and lasted longer than wood NPP.The influence of site conditions on the variation in wood and root NPP of beech was stronger than that of stand type.Wood NPP was,as expected,higher at the richer site than at the poorer site.In contrast,root NPP was higher at the poorer than at the richer site.We concluded that beech can respond to limited resources not only above-but also belowground and that the negative relationship between above-and belowground growth across the study sites suggests an‘optimal partitioning’of growth under stress.

Conspecific cues and breeding territory selection in Whinchat on abandoned fields

Many bird species use social information to guide territory selection.Different species in different habitats may use both pre-breeding and post-breeding conspecific cues.Abandoned agricultural fields are of particular interest for studies of conspecific attraction because the ephemeral nature of the habitat suggests territory search just before breeding,but high predation pressure suggests the use of performance-based conspecific cues.We investigated whether post-breeding or pre-breeding social cues affect Whinchat(Saxicola rubetra)abundance at the territorial scale during a two-year experiment in abandoned fields.We assigned 27 experimental plots(3.14 ha)to one of three treatments:post-breeding treatment,pre-breeding treatment and silent control.We conducted playback experiments with fledgling calls(evidence of past reproductive success)during the post-breeding period and male songs(evidence of conspecific presence)during the pre-breeding period.We estimated the difference in Whinchat abundance in two consecutive years and tested whether this value differed between treatment and control plots.We observed a slight increase(0.67±0.29 pairs per plot)in Whinchat abundance in the post-breeding treatment plots and no significant changes in the pre-breeding(-0.22±0.32 pairs per plot)and control(-0.22±0.22 pairs per plot)plots.Our results suggest that Whinchats do not use conspecific acoustic cues during the pre-breeding period and provide limited evidence for the use of fledgling calls as conspecific cues in the post-breeding period.

Resolving a nearly 90-year-old enigma:The rare Fagus chienii is conspecific with F.hayatae based on molecular and morphological evidence

Taxonomic uncertainties of rare species often hinder effective prioritization for conservation.One such taxonomic uncertainty is the 90-year-old enigma of Fagus chienii.F.chienii was previously only known from the type specimens collected in 1935 in Pingwu County of Sichuan Province,China,and has long been thought to be on the verge of extinction.However,morphological similarities to closely related Fagus species have led many to question the taxonomic status of F.chienii.To clarify this taxonomic uncertainty,we used the newly collected samples to reconstruct a molecular phylogeny of Chinese Fagus species against the phylogenetic backbone of the whole genus using seven nuclear genes.In addition,we examined nine morphological characters to determine whether F.chienii is morphologically distinct from its putatively closest relatives(F.hayatae,F.longipetiolata,and F.lucida).Both morphological and phylogenetic analyses indicated that F.chienii is conspecific with F.hayatae.We recommended that F.chienii should not be treated as a separate species in conservation management.However,conservation strategies such as in situ protection and ex situ germplasm preservation should be adopted to prevent the peculiar“F.chienii”population from extinction.

Analysing changes in spatial point patterns:A proposal using data from a forest thinning experiment

Spatial patterns reveal critical features at the individual and community levels.However,how to evaluate changes in spatial characteristics remains largely unexplored.We assess spatial changes in spatial point patterns by augmenting current statistical functions and indices.We fitted functions to describe unmarked and marked(tree size)spatial patterns using data from a large-scale silvicultural experiment in southern Chile.Furthermore,we compute the mingling index to represent spatial tree diversity.We proffer the pair correlation function difference before and after treatment to detect changes in the unmarked-point pattern of trees and the semivariogram-ratio to evaluate changes in the marked-point pattern.Our research provides a quantitative assessment of a critical aspect of forest heterogeneity:changes in spatial unmarked and marked-point patterns.The proposed approach can be a powerful tool for quantifying the impacts of disturbances and silvicultural treatments on spatial patterns in forest ecosystems.

Trees species’ dispersal mode and habitat heterogeneity shape negative density dependence in a temperate forest

Conspecific negative density dependence(CNDD)is a potentially important mechanism in maintaining species diversity.While previous evidence showed habitat heterogeneity and species’dispersal modes affect the strength of CNDD at early life stages of trees(e.g.,seedlings),it remains unclear how they affect the strength of CNDD at later life stages.We examined the degree of spatial aggregation between saplings and trees for species dispersed by wind and gravity in four topographic habitats within a 25-ha temperate forest dynamic plot in the Qinling Mountains of central China.We used the replicated spatial point pattern(RSPP)analysis and bivariate paircorrelation function(PCF)to detect the spatial distribution of saplings around trees at two scales,15 and 50 m,respectively.Although the signal was not apparent across the whole study region(or 25-ha),it is distinct on isolated areas with specific characteristics,suggesting that these characteristics could be important factors in CNDD.Further,we found that the gravity-dispersed tree species experienced CNDD across habitats,while for wind-dispersed species CNDD was found in gully,terrace and low-ridge habitats.Our study suggests that neglecting the habitat heterogeneity and dispersal mode can distort the signal of CNDD and community assembly in temperate forests.

The spatial distribution and breeding behavior of neighbors affect the reproductive success of tits

The spatial distribution and breeding behavior of neighboring birds(conspecific and heterospecific)may influence reproduction and the effects differ across species.In this study,we investigated intra-and inter-specific spatial distribution of breeding via artificial nestboxes and examined whether overlap with neighbors affected reproductive success of the focal breeding pair.Regarding spatial distribution,Varied Tits(Sittiparus varius)and Cinereous Tits(Parus cinereus)showed similar pattern:distances of nestboxes containing conspecific tits were greater than those with heterospecific ones.In terms of breeding behavior,reproductive success was not significantly related to the distance from their neighbor’s nest.The reproductive success of Varied Tits was significantly related to that of their neighbors,while in Cinereous Tits,no strong link was found to any recorded reproductive behavior of the neighbors.These findings explain spatial variation in nest site selection of Varied Tits and Cinereous Tits.Reproductive success rate of Varied Tits is affected by that of the neighbors while that of Cinereous Tits is not.The results highlight that there are differences in reproductive outcome among related species and offer suggestions on the use of artificial nestboxes in experiment and conservation programs.

Volatiles induced by the larvae of the Asian corn borer （Ostrinia furnacalis） in maize plants affect behavior of conspecific larvae and female adults

Effects of maize （Zea mays L.） volatiles induced by larvae of the Asian corn borer, Ostriniafurnacalis （Guenee）, on the orientation behaviors of Asian corn borer larvae and oviposition of the females were investigated. Nineteen volatile chemicals, with terpenes being the major components, were identified from maize plants attacked by third instar Asian corn borer larvae. Coupled gas chromatographic-electroantennographic detection （GC-EAD） analyses revealed some electroantennographic differences between female and male Asian corn borer antennae in response to larvae-induced maize volatiles; female responded to （E）-2-hexenal, nonanal, （Z）-3-hexen-l-ol and three unknown compounds while the male only responded to （E）-2-hexenal, nonanal and one unknown compound. In laboratory orientation bioassays, Asian corn borer neonate larvae were attracted to extracts collected from Asian corn borer-damaged plants as well as to synthetic farnesene, but were repelled by （Z）-3-hexen- 1 -ol. In laboratory oviposition bioassays, gravid females laid fewer eggs on plants damaged by larvae than on mechanically damaged plants or undamaged plants. Adult Asian corn borer females deposited fewer eggs on wax paper treated with （E）-2-hexenal or （Z）-3-hexen-l-ol than on wax paper treated with hexane （control）. The results suggest that Asian corn borer can affect the behaviors of conspecific larvae and adults by changing host plant volatiles.

Taxonomic revisionofthegenus Lactarius(Russulales,Basidiomycota)in Korea

The genus Lactarius Pers.(Russulales)is a cosmopolitan group of Basidiomycota that forms ectomycorrhizal relationships primarily with both deciduous and coniferous trees.Although the genus has been well-studied in Europe and North America,only fragmentary researches have been carried out on Asian species.In particular,the distribution of Lactarius species in South Korea is poorly understood due to insufficient morphological descriptions and a lack of DNA sequence data.In addition,the misuse of European and North American names has added to confusion regarding the taxonomy of Asian Lactarius species.In this study,the diversity of Lactarius in South Korea was evaluated by employing both morphological and phylogenetic approaches.A multi-locus phylogenetic analysis of 729 Lactarius specimens collected between 1960 and 2017 was performed using the internal transcribed spacer(ITS)region,partial nuclear ribosomal large subunit(nrLSU),partial second largest subunit of RNA polymerase II(rpb2),and minichromosome maintenance complex component 7(mcm7).49 Lactarius species were identified in three Lactarius subgenera:L.subg.Russularia(17 spp.),L.subg.Lactarius(22 spp.),and L.subg.Plinthogalus(10 spp.).Among them,28 Lactarius species were identified as new to science,while just 17 were previously described Lactarius species.Four of the taxa remain un-named due to paucity of materials.A key to Korean Lactarius species,molecular phylogenies,a summary of diversity,and detailed description are provided.

Rufous-and-white wrens Thryophilus rufalbus do not exhibit a dear enemy effects towards conspecific or heterospecific competitors

Many territorial animals exhibit reduced aggression towards neighbours. Known as ＂the dear enemy effect＂, this phenomenon has been documented among conspecific animals across a wide range of animal taxa. In theory, the dear enemy ef- fect can also exist between individuals of different species, particularly when those species compete for shared resources. To date, a heterospecific dear enemy effects has only been documented in ants. In this study, we test for both a conspecific and heterospe- cific dear enemy effect in neotropical rufous-and-white wrens Thryophilus rufalbus. This species competes for resources with banded wrens Thryophilus pleurostictus, a closely related sympatric congener. We used acoustic playback to simulate ruf- ous-and-white wren and banded wren neighbours and non-neighbours at the edges of rufous-and-white wren territories. Ruf- ous-and-white wrens responded more strongly to signals from their own species, demonstrating that resident males discriminate between conspecific and heterospecific rivals. They did not, however, exhibit a conspecific dear enemy effect. Further, they did not exhibit a heterospecific dear enemy effect. This could be due to neighbours and non-neighbours posing similar levels of threat in this system, to the possibility that playback from the edges of the subjects＇ large territories did not simulate a threatening signal, or to other factors. Our study provides the first test of a heterospecific dear enemy effect in vertebrates, and presents a valuable experimental approach for testing for a heterospecific dear enemy effect in other animals [Current Zoology 61 （1）： 23-33, 2015].

Differential impacts of adult trees on offspring and non-offspring recruits in a subtropical forest

An important mechanism promoting species coexistence is conspecific negative density dependence(CNDD),which inhibits conspecific neighbors by accumulating host-specific enemies near adult trees.Natural enemies may be genotype-specific and regulate offspring dynamics more strongly than non-offspring,which is often neglected due to the difficulty in ascertaining genetic relatedness.Here,we investigated whether offspring and non-offspring of a dominant species,Castanopsis eyrei,suffered from different strength of CNDD based on parentage assignment in a subtropical forest.We found decreased recruitment efficiency(proxy of survival probability)of offspring compared with non-offspring near adult trees during the seedling-sapling transition,suggesting genotype-dependent interactions drive tree demographic dynamics.Furthermore,the genetic similarity between individuals of same cohort decreased in late life history stages,indicating genetic-relatedness-dependent tree mortality throughout ontogeny.Our results demonstrate that within-species genetic relatedness significantly affects the strength of CNDD,implying genotype-specific natural enemies may contribute to population dynamics in natural forests.