Individual recognition of neighbors by song in a suboscine bird, the alder flycatcher Empidonax alnorum

The ability of territorial males to discriminate between songs of their neighbors and songs of strangers has been demonstrated in 27 species of songbirds. Such experiments test only the ability of a subject to discriminate between two classes of stimuli, familiar (neighbors) and unfamiliar (strangers) songs. Individual recognition of neighbors is a finer, more complex type of discrimination. The ability of territorial males to recognize individual neighbors by song has been documented in 12 species of oscine passerines (Passeriformes, Passeri), but has never been demonstrated in suboscine passerines (Tyranni). We investigated recognition of songs of individual neighbors in a suboscine, the alder flycatcher (Empidonax alnorum). We performed a series of song playback experiments and recorded responses of territorial males to songs of neighbors and songs of strangers broadcast from two locations, the neighbor boundary and an opposite boundary. Subjects responded more aggressively to songs of a neighbor when played from the opposite boundary than when played from the neighbor boundary. They responded with equal aggression to songs of strangers regardless of location of playback. The difference in response to neighbor songs between speaker locations and the lack of a difference in response to stranger songs indicate that territorial males associate a particular song with a particular location (territory), and thus recognize individual neighbors.Communicated by I. Hartley     

Nestmate recognition for eggs in the honeybee (<Emphasis Type="Italic">Apis mellifera</Emphasis> L.)

Colony integrity is fundamental to social insects and is threatened by the reproduction of non-nestmates. Therefore, discrimination between eggs derived from nestmates and non-nestmates would constitute an adaptation to prevent exploitation of the entire cooperative group by unrelated individuals. The removal of nestmate and non-nestmate queen and worker-laid eggs was evaluated in honeybees using colonies of Apis mellifera capensis to test female and of A. m. scutellata to test male eggs. The data show that honeybees can distinguish between nestmate and non-nestmate eggs of both sexes. Moreover, non-nestmate female queen-laid eggs were removed significantly faster than nestmate female worker-laid eggs in A. m. capensis, indicating that nestmate recognition cues can override caste-specific ones. While the experimental manipulation accounts for 37.2% (A. m. scutellata) or 1.6% (A. m. capensis) of variance in relation to egg removal, nestmate recognition explains 33.3% for male eggs (A. m. scutellata) and 60.6% for female eggs (A. m. capensis), which is almost twice as high as the impact of caste (16.7% A. m. scutellata; 25% A. m. capensis). Our data show a stronger effect of nestmate recognition on egg removal in the honeybee, suggesting that cues other than caste-specific ones (viability/kin) can dominate egg removal behavior. In light of intraspecific social parasitism, preventing the reproduction of unrelated individuals (group selection) rather than preferring queens’ eggs (kin selection) appears to be the driving force behind the evolution of egg removal behavior in honeybees.     

Persistence of individually distinctive display patterns in fatigued side-blotched lizards ( Uta stansburiana)

Iguanian lizards perform conspicuous species-typical push-up displays, which are used in territory advertisement, threat, and courtship contexts. Subtle individually distinctive differences in push-up characteristics have been suggested to play a role in the recognition of social partners. However, if the structure of push-ups is responsive to changing physiological states then their capacity to promote recognition may be limited. The current study evaluated whether the push-ups performed while in an experimentally imposed state of fatigue by male side-blotched lizards (Uta stansburiana), retain the individually distinctive characteristics apparent in rested lizards. We found repeatable among-individual differences in the duration and the relative height of push-up components. Repeatability values did not change consistently between the rested and fatigued conditions, nor when both conditions were pooled, indicating that these push-up characteristics do not change with fatigue. Similarly, discriminant functions that were generated using push-ups from one state assigned push-ups performed in an alternate state to the correct individuals. Furthermore, when analyzed independently of individual identity, the values of display parameters examined in the current study did not change significantly between states, and discriminant function analysis could not reliably classify push-ups to the correct state. Taken together the results show that individually distinctive push-up characteristics are robust to effects of fatigue, consistent with their suggested role in social recognition. In the future, video playback experiments can test whether lizards utilize the signature-like characteristics of push-ups to discriminate among individuals.Communicated by T. Czeschlik     

Interpopulational differences in chemical composition and chemosensory recognition of femoral gland secretions of male lizards Podarcis hispanica: implications for sexual isolation in a species complex

Summary. Molecular studies suggest that the Iberian wall lizard, Podarcis hispanica, forms a species complex with several monophyletic types. In Central Spain two of these types are spatially not isolated and may interact. Sex pheromones are important for species recognition and, thus, differences between lizards’ types in chemicals used in intraspecific communication could lead to reproductive isolation. Analyses by GC-MS showed that the femoral gland secretions of adult males of different types were different. Males of one type had twelve exclusive compounds, and proportions of some shared compounds differed. This presumably would reflect selection for the persistency and efficiency of chemical signals in different environments; less volatile compounds and with a higher chemical stability being favoured in the type of lizards inhabiting more humid climatic conditions. Differential tongue-flick rates to scents from femoral secretions indicated that males were able to detect and discriminate between males of different types based on chemical cues alone. In contrast, females detected but did not seem able to discriminate between scents of the two types of males. Thus, multiple factors might be simultaneously acting either against or in favor of speciation, leading, on the one hand, to genetic differences between types, but, on the other hand, probably precluding an effective reproductive isolation in areas where both types of lizards may interact.     

Food influence on colonial recognition and chemical signature between nestmates in the fungus-growing ant <Emphasis Type="Italic">Acromyrmex subterraneus subterraneus</Emphasis>

Summary. Neotropical Fungus-growing leaf-cutting ants (tribe Attini) live in obligatory symbiosis with a fungus, which they grow on fresh leaves harvested by workers. Colonial recognition is likely based on chemical cues provided by cuticular hydrocarbons that have been found to be partly influenced by environmental odor sources. The diet breadth of Acromyrmex subterraneus subterraneus enabled us to test the impact of different plant diets on colonial recognition. The intermediary of the fungus in the ants feeding habit adds a special angle to the question. From a queenright (QR) mother colony of A. s. subterraneus we formed several groups of queenless (QL) workers with fungus (approx. 700 ants). The QR colony and two of the QL-groups were fed with the same diet of fresh bramble leaves. Two other QL-groups were fed with privet leaves and two with rose flowers. After 4 months, QR workers were significantly more aggressive towards the QL-group fed with rose flowers or privet leaves than towards workers of the QL-groups fed with fresh bramble leaves. Rose-fed QL workers were aggressive towards privet-fed QL workers and vice versa, but never towards workers of their counterpart group that fed on the same diet. These results suggest that the absence of the queen or the separation time between groups played a minor role in shaping nestmate recognition cues as compared to the diet. The behavioral studies were supplemented by chemical analyses of cuticles, postpharyngeal glands (PPG) and plant-food extracts revealing profiles variations that were correlated with the dietary changes. However, although the plant extract contained several hydrocarbons there was no congruency between the plant profile and the respective diet-group ants. These results support the hypothesis that the diet influences indirectly the chemical profiles and consequently the recognition cues in A. s. subterraneus.     

Hibernation clustering and its consequences for associative nest foundation in<Emphasis Type="Italic"> Polistes dominulus</Emphasis> (Hymenoptera Vespidae)

Various studies indicate that cuticular hydrocarbons (CHCs) act as cues for nestmate recognition in paper wasps and other social insects. A recent study showed that associative nest foundation in Polistes dominulus is mainly performed by foundresses coming from the same locality. In the present study, we induced future foundresses of P. dominulus collected in two different localities to hibernate in the laboratory in aggregates of individuals from the same or different localities. After 2 months of hibernation, foundresses from different localities but from the same experimental cluster did not show any preference to associate, at the time of nest foundation, with individuals coming from the same original locality. The cuticular chemical profiles of individuals from the mixed hibernation clusters were quite similar and significantly different from those of individuals which hibernated with other foundresses from the same locality. These findings suggest that, in this species, mechanisms other than nestmate chemical recognition play a major role in the spring association of gynes during the foundation of a new nest.Communicated by R.F.A. Moritz     

基于K-means聚类的沙尘天气快速识别技术研究

依据沙尘天气判定条件分析2018年春季（2—4月）陕西省西安市环境空气质量小时监测数据，共识别9 d受沙尘影响。研究基于K-means聚类沙尘天气分析方法，分析沙尘天气监测数据特征，并对沙尘识别聚类模型进行优化研究，识别的沙尘影响天气与传统方法一致。分析表明，聚类方法可用于沙尘天气监测数据的识别，与传统方法相比较，基于K-means聚类方法能够快速、准确识别沙尘影响天气。     

大气质量综合评价的变权识别模型及其应用

根据属性识别理论 ,建立大气质量综合评价的变权识别模型 ,利用污染贡献率确定权重系数。与其它评价模型相比 ,变权识别模型还具有排序功能 ,实例分析表明该模型是有效的     

属性识别理论模型二级评判法在城市总体环境质量评价中的运用

属性识别理论模型是近年来提出的一种数学模型，它已成功地用于质量评价中。现将该模型引用到城市总体环境质量评价中，提出运用二级评判来综合评价城市总体环境质量。经实例分析表明，属性识别理论模型用于城市总体环境质量评价比模糊综合二级评判法更合理实用，为城市总体环境质量综合评价提供了一种新方法。     

基于自组织映射与随机森林耦合模型的流域水质空间差异性评估

流域水环境质量空间分布特征分析是推进流域精细化管理的基础.本研究基于流域特征指标与水质的关联性,以子流域为分析单元,利用自组织映射人工神经网络模型（SOM）对苕溪流域水质数据聚类分析为3类后与随机森林模型（RF）进行耦合,对全流域水质进行了空间差异性评估.研究结果显示,上游山地区域水质较好,而平原河网人口集聚区的COD_Mn、NH₃-N及TP浓度较高,山地与平原过渡地带水质则主要受到COD_Mn和TN的影响.采用自然环境、社会经济及土地利用/覆盖指标作为流域特征进行水质分级模式识别,SOM与RF模型耦合模型的准确率稳定在80%左右;在对强相关性特征进行筛选识别后,将蒸发蒸腾量、坡度、人口密度、大于10℃积温、旱地占比、城镇用地占比及景观多样性指数为作为输入特征,准确率可达83%,可以有效地开展全流域水质分级评估.