136 research outputs found

    Worker policing by egg eating in the ponerine ant Pachycondyla inversa

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    We investigated worker policing by egg eating in the ponerine ant Pachycondyla inversa, a species with morphologically distinct queens and workers. Colonies were split into one half with the queen and one half without. Workers in queenless colony fragments started laying unfertilized male eggs after three weeks. Worker-laid eggs and queen-laid eggs were introduced into five other queenright colonies with a single queen and three colonies with multiple queens, and their fate was observed for 30 min. Significantly more worker-laid eggs (range of 35–62%, mean of 46%) than queen-laid eggs (range of 5–31%, mean of 15%) were eaten by workers in single-queen colonies, and the same trend was seen in multiple-queen colonies. This seems to be the first well-documented study of ants with a distinct caste polymorphism to show that workers kill worker-laid eggs in preference to queen-laid eggs. Chemical analyses showed that the surfaces of queen-laid and worker-laid eggs have different chemical profiles as a result of different relative proportions of several hydrocarbons. Such differences might provide the information necessary for differential treatment of eggs. One particular alkane, 3,11-dimeC27, was significantly more abundant on the surfaces of queen-laid eggs. This substance is also the most abundant compound on the cuticles of egg layers

    Larval learning affects adult nest-mate recognition in the ant Aphaenogaster senilis

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    Relatório de estágio do mestrado em Ensino da Educação Física nos Ensinos Básico e Secundário, apresentada à Faculdade de Ciências do Desporto e Educação Física da Universidade de CoimbraO Mestrado em Ensino da Educação Física nos Ensino Básico e Secundário da Faculdade de Ciências do Desporto e Educação Física da Universidade de Coimbra, engloba uma componente prática que permite a profissionalização, através do aprofundamento alargado dos conhecimentos de intervenção profissional na área de Educação Física. O presente documento denominado Relatório Final do Estágio Pedagógico, foi produzido com o propósito de descrever todo o processo de aprendizagem realizado ao longo da nossa intervenção pedagógica na Escola Básica 2,3/S Dr. Daniel de Matos - Vila Nova de Poiares, com a turma do 9º B no presente ano letivo. Deste modo, todo este documento contempla um conjunto de tarefas inerentes ao processo de ensino-aprendizagem que permite a organização, realização, avaliação e reflexão de todo o processo pedagógico. O relatório apresenta-se estruturado de acordo com as atividades desenvolvidas, iniciando com o primeiro capítulo, onde refletimos sobre Expectativas e Opções Iniciais em Relação ao Estágio. Seguimos com a Análise Reflexiva da Prática Pedagógica, mais precisamente no que respeita ao Planeamento; Realização e Avaliação. Passamos para a reflexão da Atitude Ético-Profissional, à Justificação das Opções Tomadas, e uma Síntese Conclusiva no âmbito de toda a nossa intervenção pedagógica. Por último e não menos importante, temos o segundo capítulo, referente ao tema problema - A influência das aulas de educação física no âmbito do programa “Toca a Mexer” na Coordenação Motora de crianças com NEE, que iremos tratar mais adiante. Palavras-chave: Reflexão. Docência. Competências. Pratica Pedagógica. Coordenação Motora. Abstract The Master of Education Physical Education in Elementary and Secondary Education of the Faculty of Sport Sciences and Physical Education, University of Coimbra, includes a practical component that enables professional, by deepening broadened the professional intervention of knowledge in Physical Education. This document called Final Report of the Teacher Training, was produced for the purpose of describing the whole process of learning done throughout our educational intervention in Primary School 2.3 / S Dr. Daniel de Matos - Vila Nova de Poiares, with 9th class B in this school year. Thus, throughout this document includes a set of tasks of teaching-learning process that allows the organization, implementation, evaluation and reflection of the entire educational process. The report is structured according to the activities, starting with the first chapter, where we reflect on expectations and Start Options in Relation to Stage. We follow with the Reflective Analysis of Teaching Practice, specifically with regard to planning; Achievement and Assessment. We passed to the reflection of Ethical and Professional Attitude, the justification of the options sockets, and a Conclusive Synthesis under all our pedagogical intervention. Last but not least, we have the second chapter, referring to the theme problem - The influence of physical education classes under the program "Play to Stir"on the Motor Coordination of children with SEN, which we will address later

    The Scent of Ant Brood : Caste Differences in Surface Hydrocarbons of Formica exsecta Pupae

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    Chemical communication is common across all organisms. Insects in particular use predominantly chemical stimuli in assessing their environment and recognizing their social counterparts. One of the chemical stimuli used for recognition in social insects, such as ants, is the suite of long-chain, cuticular hydrocarbons. In addition to providing waterproofing, these surface hydrocarbons serve as a signature mixture, which ants can perceive, and use to distinguish between strangers and colony mates, and to determine caste, sex, and reproductive status of another individual. They can be both environmentally and endogenously acquired. The surface chemistry of adult workers has been studied extensively in ants, yet the pupal stage has rarely been considered. Here we characterized the surface chemistry of pupae of Formica exsecta, and examine differences among sexes, castes (reproductive vs. worker), and types of sample (developing individual vs. cocoon envelope). We found quantitative and qualitative differences among both castes and types of sample, but male and female reproductives did not differ in their surface chemistry. We also found that the pupal surface chemistry was more complex than that of adult workers in this species. These results improve our understanding of the information on which ants base recognition, and highlights the diversity of surface chemistry in social insects across developmental stages.Peer reviewe

    Quantitative cognition in carpenter ants

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    P.dE. is funded by ‘Institut Universitaire de France (IUF)’.Processing information about quantities allows animals to make optimal decisions during many natural contexts, such as foraging, territorial defense, offspring care, mate choice, and intra-sexual competition. Compared to the wealth of information available in vertebrates, much less is known in invertebrates, even though the processing of quantities is equally relevant for both taxa. Here, we used two separate ecologically relevant tasks (brood pile preference and landmark-guided foraging) to investigate two dimensions of quantitative cognition in carpenter ants: spontaneous quantitative judgments and trained use of sequential landmarks. Individual ants spontaneously discriminated between two piles of dummy cocoons both when the choice involved smaller (1 vs. 2, 3, 4) and larger numerical contrasts (2 vs. 4, 6, 8). Ants used both chemical and visual/tactile cues and their performance was dependent on the numerical ratio. In the second task, ants preferentially searched near the trained landmark (out of five identical ones) despite alterations in its position, suggesting that they used ordinal information about its location when searching for food. In this experiment, ants showed a limit at four since their performance drastically decreased when they were trained to the 5th landmark. We showed that carpenter ants use both relative quantity and relative position to make efficient decisions. Our study contributes to the scant body of knowledge available on quantitative cognition in invertebrate species.PostprintPeer reviewe

    Low levels of nestmate discrimination despite high genetic differentiation in the invasive pharaoh ant

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    <p>Abstract</p> <p>Background</p> <p>Ants typically distinguish nestmates from non-nestmates based on the perception of colony-specific chemicals, particularly cuticular hydrocarbons present on the surface of the ants' exoskeleton. These recognition cues are believed to play an important role in the formation of vast so-called supercolonies that have been described for some invasive ant species, but general conclusions about the role of these cues are hampered by only few species being studied. Here we use data on cuticular hydrocarbons, aggression and microsatellite genetic markers to investigate the interdependence of chemical recognition cues, genetic distance and nestmate discrimination in the pharaoh ant (<it>Monomorium pharaonis</it>), a widespread pest species, and ask whether introduced populations of this species are genetically differentiated and exhibit intraspecific aggression.</p> <p>Results</p> <p>Microsatellite analyses of a total of 35 colonies from four continents revealed extremely high levels of genetic differentiation between almost all colonies (<it>F</it><sub>ST </sub>= 0.751 ± 0.006 SE) and very low within-colony diversity. This implies that at least 34 and likely hundreds more independent lineages of this ant have spread worldwide. Aggression tests involving workers from 14 different colonies showed only low levels of aggression, even between colonies that were geographically and/or genetically very distant. Chemical analyses of groups of worker ants showed that all colonies had the same cuticular compounds, which varied only quantitatively among colonies. There was a positive correlation between geographical and genetic distance, but no other significant relationships were detected between aggression, chemical profile, genetic distance and geographical distance.</p> <p>Conclusions</p> <p>The pharaoh ant has a global invasion history of numerous independent introductions resulting in genetically highly differentiated colonies typically displaying surprisingly low levels of intraspecific aggression, a behaviour that may have evolved in the native range or by lineage selection in the introduced range.</p
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