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1.
Antagonistic or mutualistic interactions between insects and fungi are well-known, and the mutualistic interactions of fungus-growing ants, fungus-growing termites, and fungus-gardening beetles with their respective fungal mutualists are model examples of coevolution. However, our understanding of coevolutionary interactions between insects and fungi has been based on a few model systems. Fungal mimicry of termite eggs is one of the most striking evolutionary consequences of insect–fungus associations. This novel termite–fungus interaction is a good model system to compare with the relatively well-studied systems of fungus-growing ants and termites because termite egg-mimicking fungi are protected in the nests of social insects, as are fungi cultivated by fungus-growing ants and termites. Recently, among systems of fungus-growing ants and termites, much attention has been focused on common factors including monoculture system for the ultimate evolutionary stability of mutualism. We examined the genetic diversity of termite egg-mimicking fungi within host termite nests. RFLP analysis demonstrated that termite nests were often infected by multiple strains of termite egg-mimicking fungi, in contrast to single-strain monocultures in fungus combs of fungus-growing ants and termites. Additionally, phylogenetic analyses indicated the existence of a free-living stage of the termite egg-mimicking fungus as well as frequent long-distance gene flow by spores and subsequent horizontal transmission. Comparisons of these results with previous studies of fungus-growing ants and termites suggest that the level of genetic diversity of fungal symbionts within social insect nests may be important in shaping the outcome of the coevolutionary interaction, despite the fact that the mechanism for achieving genetic diversity varies with the evolutionary histories of the component species.  相似文献   

2.
Shimoji  H.  Oguchi  K.  Hayashi  Y.  Hojo  M. K.  Miura  T. 《Insectes Sociaux》2017,64(3):393-401
Insectes Sociaux - In cooperative societies such as those of ants, honey bees, and termites, the number of reproductives is often regulated by social interactions. In many termite species, helper...  相似文献   

3.
The importance of termites as decomposers in tropical forests has long been recognized. Studies on the richness and diversity of termite species and their ecological function have flourished in more recent times, but these have been mostly conducted in a thin stratum within a standing man’s reach. Our aims were to evaluate the specific richness and composition of the termite assemblage in the canopy of a tropical rainforest and to determine its originality with respect to the sympatric ground-level fauna. We conducted systematic searches for canopy termites, together with conventional sampling of the sympatric ground-level fauna, in the San Lorenzo forest, Panama. We hypothesized that (1) the canopy accommodates two categories of wood-feeding termites (long-distance foragers and small-colony “one-piece” species) and possibly soil-feeders in suspended soil-like habitats; (2) due to the abundance of soil-feeders, the overall diversity of the ground fauna is higher than that of the canopy; (3) differences in microclimate and resource accessibility favour vertical stratification among wood-feeders. Sixty-three canopy samples yielded ten species of termites, all wood-feeders. Five of these were not found at ground level, although a total of 243 ground samples were collected, representing 29 species. In addition to long-distance foragers (Microcerotermes and Nasutitermes spp.) and small-colony termites (mostly Kalotermitidae), the canopy fauna included Termes hispaniolae, a wood-feeding Termitidae from an allegedly soil-feeding genus, living in large dead branches. Soil-feeders were absent from the canopy, probably because large epiphytes were scarce. As predicted, the ground fauna was much richer than that of the canopy, but the species richness of both habitats was similar when only wood-feeders were considered. Vertical stratification was strongly marked among wood-feeders, as all common species, apart from the arboreal-nesting Microcerotermes arboreus, could unequivocally be assigned to either a ground or a canopy group. The canopy, therefore, contributes significantly to the total species richness of the termite assemblage, and the diversity, abundance and ecological importance of canopy termites in tropical rainforests may be higher than previously recognized.Electronic Supplementary Material Supplementary material is available to authorized users in the online version of this article at .  相似文献   

4.
We present a model of tunnel excavation by termites that requires no pheromone labeling of soil or work sites, but instead relies on tactile interactions and individuals who actively orient their movement. Potential termite excavators moved from the tunnel origin towards the distal end of the tunnel and formed a queue behind those termites at the digging face. Delayed termites excavated soil laterally from the tunnel wall at a position governed by their position in the queue of termites. By examining excavation under artificially induced conditions of longer and shorter queues of termites at the tunnel end, we showed that tunnel width increased with increased queue size and the rate of lateral excavation in a process we termed “digging pressure.”  相似文献   

5.
Basic elements of cognition have been identified in the behaviour displayed by animal collectives, ranging from honeybee swarms to human societies. For example, an insect swarm is often considered a ??super-organism?? that appears to exhibit cognitive behaviour as a result of the interactions among the individual insects and between the insects and the environment. Progress in disciplines such as neurosciences, cognitive psychology, social ethology and swarm intelligence has allowed researchers to recognise and model the distributed basis of cognition and to draw parallels between the behaviour of social insects and brain dynamics. In this paper, we discuss the theoretical premises and the biological basis of Swarm Cognition, a novel approach to the study of cognition as a distributed self-organising phenomenon, and we point to novel fascinating directions for future work.  相似文献   

6.
Timo Maran 《Biosemiotics》2010,3(3):315-329
In the current debates about zoosemiotics its relations with the neighbouring disciplines are a relevant topic. The present article aims to analyse the complex relations between zoosemiotics and cognitive ethology with special attention to their establishers: Thomas A. Sebeok and Donald R. Griffin. It is argued that zoosemiotics and cognitive ethology have common roots in comparative studies of animal communication in the early 1960s. For supporting this claim Sebeok’s works are analysed, the classical and philosophical periods of his zoosemiotic views are distinguished and the changing relations between zoosemiotics and cognitive ethology are described. The animal language controversy can be interpreted as the explicit point of divergence of the two paradigms, which, however, is a mere symptom of a deeper cleavage. The analysis brings out later critical differences between Sebeok’s and Griffin’s views on animal cognition and language. This disagreement has been the main reason for the critical reception and later neglect of Sebeok’s works in cognitive ethology. Sebeok’s position in this debate remains, however, paradigmatic, i.e. it proceeds from understanding of the contextualisation of semiotic processes that do not allow treating the animal mind as a distinct entity. As a peculiar parallel to Griffin’s metaphor of “animal mind”, Sebeok develops his understanding of “semiotic self” as a layered structure, characterised by an ability to make distinctions, foremost between itself and the surrounding environment. It appears that the history of zoosemiotics has two layers: in addition to the chronological history starting in 1963, when Sebeok proposed a name for the field, zoosemiotics is also philosophically rooted in Peircean semiotics and German biological philosophy. It is argued that the confrontation between zoosemiotics and cognitive ethology is related to different epistemological approaches and at least partly induced by underlying philosophical traditions.  相似文献   

7.
While self-assembly is a fairly active area of research in swarm intelligence, relatively little attention has been paid to the issues surrounding the construction of network structures. In this paper we extend methods developed previously for controlling collective movements of agent teams to serve as the basis for self-assembly or “growth” of networks, using neural networks as a concrete application to evaluate our approach. Our central innovation is having network connections arise as persistent “trails” left behind moving agents, trails that are reminiscent of pheromone deposits made by agents in ant colony optimization models. The resulting network connections are thus essentially a record of agent movements. We demonstrate our model’s effectiveness by using it to produce two large networks that support subsequent learning of topographic and feature maps. Improvements produced by the incorporation of collective movements are also examined through computational experiments. These results indicate that methods for directing collective movements can be adopted to facilitate network self-assembly.  相似文献   

8.
The behavior of wild chimpanzees at Bossou, Guinea, was studied from November 1976 to May 1977 recognizing each chimpanzee without artificial feeding. During the study period some tool-using and tool-making behavior was observed, as follows: (1) Although water drinking using a “leaf-sponge” was not seen, that using a “leaf-spoon” was observed for taking water from the hollow of a tree. (2) “Termite fishing” was not seen in this group although there were many termite hills in the moving range of the chimpanzees. They dug termites from the hollow of a tree by pounding with a small stick. Similar use of a stick was made for digging up the resin from a tree. (3) “Aimed throwing” was frequently observed in adult males for attacking an observer, and in adolescents and juveniles as mischief against an observer or for their own play. (4) “Nut cracking” with a pair of stones was seen for removing the ovule from palm-seeds. Particular stones were repeatedly used by many chimpanzees for a long period. (5) “Branch hauling” represented difficult work. Patient and inventive manufacture of proper sticks was necessary for capturing branches which they were unable to reach normally. Local variations in the tool-using patterns and manufacturing ability of chimpanzees are discussed.  相似文献   

9.
Hymenoptera have haploid males, which produce sperm by cloning. Sperm selection theory predicts that because termites have diploid males that produce genetically diverse sperm, they may profit from a high sperm surplus (large K), whereas Hymenoptera (ants, bees and wasps) should produce few sperm per fertilization (low Κ). Male reproductive “kings”, which continuously provide spermatozoa during the whole life of the queen, allow for a large K. Available empirical evidence confirms the existence of a large difference in K between diploid insects, especially Blattodea (Isoptera) (> 1,000), and haplo-diploids such as Hymenoptera (< 10). The available data suggest that sperm selection may be an important evolutionary force for species with diploid, but not haploid males.  相似文献   

10.
We consider a previously unknown way of propagation of behavioural traditions in animal communities using hunting in ants as an example. We experimentally revealed that common litter dwelling ants Myrmica rubra effectively hunt jumping prey and the way the hunting behavioural pattern is distributed within ant colonies is rather sophisticated. Comparison of our results with those obtained on vertebrates enables us to suggest that “distributed social learning” plays an important role in spreading new traditions in animal communities: initial performances by a few carriers of an “at once and entirely” available behavioural pattern propagate this pattern among specimens which have only dormant “sketches” of it. Spread of these behaviours in populations is based on relatively simple forms of social learning such as social facilitation which underlies species’ predisposition to learn certain sequences of behavioural acts. To be triggered, carriers of dormant “sketches” of a relevant behavioural pattern should encounter performances of this pattern with sufficient frequency. We call this strategy triggering of dormant behavioural patterns. Integration of behaviour thus takes place not only at the individual level but at the population level as well.  相似文献   

11.
Predation pressure from ants is a major driving force in the adaptive evolution of termite defense strategies and termites have evolved elaborate chemical and physical defenses to protect themselves against ants. We examined predator–prey interactions between the woodland ant, Aphaenogaster rudis (Emery) and the eastern subterranean termite, Reticulitermes flavipes (Kollar), two sympatric species widely distributed throughout deciduous forests in eastern North America. To examine the behavioral interactions between A. rudis and R. flavipes we used a series of laboratory behavioral assays and predation experiments where A. rudis and R. flavipes could interact individually or in groups. One-on-one aggression tests revealed that R. flavipes are vulnerable to predation by A. rudis when individual termite workers or soldiers are exposed to ant attacks in open dishes and 100% of termite workers and soldiers died, even though the soldiers were significantly more aggressive towards the ants. The results of predation experiments where larger ant and termite colony fragments interacted provide experimental evidence for the importance of physical barriers for termite colony defense. In experiments where the termites nested within artificial nests (sand-filled containers), A. rudis was aggressive at invading termite nests and inflicted 100% mortality on the termites. In contrast, termite mortality was comparable to controls when termite colonies nested in natural nests comprised of wood blocks. Our results highlight the importance of physical barriers in termite colony defense and suggest that under natural field conditions termites may be less susceptible to attacks by ants when they nest in solid wood, which may offer more structural protection than sand alone.  相似文献   

12.
13.
The human brain is a complex organ made up of neurons and several other cell types, and whose role is processing information for use in elicitation of behaviors. To accomplish this, the brain requires large amounts of energy, and this energy is obtained by the oxidation of glucose (Glc). However, the question of how the oxidation of Glc by individual neurons in brain results in their collective ability to rapidly generate feats of cognition that allow them to recognize the nature of the universe in which they live and to communicate this information remains unclear. In this article, insights into this process are provided by first considering the brain’ s homeostatic “operating system” for supply of energy to stimulated neurons, and how this system defines the basic unit of brain “structure”. This is followed by consideration of the brain’s “two-cell” neuronal communication mechanism which defines the basic unit of brain “function”. Finally, an analysis of the nature of frequency-encoded “neuronal languages” that enable ensembles of neurons to translate energy derived from the oxidation of Glc into a collective “mind”, the aggregate of all brain processes including those involving perception, thought, insight, foresight, imagination and behavior.  相似文献   

14.
Embodied, situated and enactive aspects of relationships of polistine wasps with ants are considered within the framework of the theory of autopoiesis. The idea of the embodied interaction implies specific nestbuilding and protective behavior in polistine wasps. The paper examines the adaptive role of applying ant repellent on the petiole and nest and the latitude gradient of such behavior in re-social wasp species. The situated interaction is considered in the environmental context: the mortality of Polistes gallicus (L.) colonies as a result of predatory attacks of ants Myrmica bergi Ruzsky is analyzed in the Lower Dnieper basin (Ukraine). The enactive interaction includes both spontaneous autonomous activity of its participants as a result of self-organization and specific features of the spatial structure of the prey’s population forming under the impact of the predator. The applicability of some “predator-prey” models is discussed.  相似文献   

15.
Ants are ubiquitous, abundant and have widespread impacts on ecological communities and ecosystem processes. However, ant effects on coarse woody debris decomposition are unexplored. Several ant species colonize coarse woody debris for nesting, and this puts them in contact with fauna and microbes that utilize coarse woody debris as habitat and food, potentially influencing nutrient cycling and, ultimately, forest productivity. We report results from a field experiment employing 138 artificial ant nests (routed pine blocks) across five locations in southeastern US deciduous forests. We examine the correspondence between ant, termite and wood-eating fungi colonization and variation in coarse woody debris decomposition. After 1 year, nests colonized by ants had 5% more mass than those not colonized. Ant colonization corresponded with significantly less termite- and fungal-mediated decomposition of the nests. Without ants, termites removed 11.5% and fungi removed 4% more wood biomass. Ants, termites and wood-eating fungi all colonized pine nests where temperatures were highest, and ants also preferred higher soil moisture whereas termites and fungi responded negatively to high soil moisture when temperatures were higher. Ants reduce termite colonies through predation, and may inhibit fungi through the secretion of antimicrobial compounds. Our results indicate that interactions between forest understory ants, termites and fungi may influence the rate of coarse woody debris decomposition—biotic interactions that potentially influence forest structure and function.  相似文献   

16.
Land use change is accelerating globally at the expense of biodiversity and ecosystem functioning. Invertebrates are numerically dominant and functionally important in old growth tropical rain forests but highly susceptible to the adverse effects of forest degradation and fragmentation. Ants (Formicidae) and termites (Blattodea: Termitoidae) perform crucial ecosystem services. Here, the potential effects of anthropogenic disturbance on ant and termite communities in dead wood are investigated. Community composition, generic richness, and occupancy rates of ants and termites were compared among two old growth sites (Danum Valley and Maliau Basin) and one twice‐logged site (the Stability of Altered Forest Ecosystems’ (SAFE) Project), in Sabah, Malaysian Borneo. Occupancy was measured as the number of ant or termite encounters (1) per deadwood items, and (2) per deadwood volume, and acts as surrogates for relative abundance (or generic richness). Termites had a lower wood‐occupancy per volume in logged forest. In contrast, there were more ant encounters, and more ant genera, in logged sites and there was a community shift (especially, there were more Crematogaster encounters). The disruption of soil and canopy structure in logged forest may reduce both termite and fungal decay rates, inducing increased deadwood residence times and therefore favoring ants that nest in dead wood. There is an anthropogenic‐induced shift of dead wood in ants and termites in response to disturbance in tropical rain forests and the nature of that shift is taxon‐specific.  相似文献   

17.
Vienna’s Institute of Experimental Biology, better known as the Vivarium, helped pioneer the quantification of experimental biology from 1903 to 1938. Among its noteable scientists were the director Hans Przibram and his brother Karl (a physicist), Paul Kammerer, Eugen Steinach, Paul Weiss, and Karl Frisch. The Vivarium’s scientists sought to derive laws describing the development of the individual organism and its relationship to the environment. Unlike other contemporary proponents of biological laws, however, these researchers created an explicitly anti-deterministic science. By “laws” they meant statistical regularities or “patterns.” They interpreted their experimental results in ways that forged a “third way” between determinism and pure spontaneity, aiming to capture the complexity of the interaction between the organism and its environment. This common feature of their research was made possible by the availability at the Vivarium of the latest in climate-control technology and of methods borrowed from statistical physics. The deeper roots of this search for a “third way” lay, I suggest, in the shared educational, social, and aesthetic experiences of the laboratory’s workers.  相似文献   

18.
Driver ants ( i.e. , epigaeic species in the army ant genus Dorylus , subgenus Anomma ) are among the most extreme polyphagous predators, but termites appear to be conspicuously absent from their prey spectrum and attacks by driver ants on termite nests have not yet been described. Here, we report a Dorylus ( Anomma ) rubellus attack on a colony of the fungus-growing termite Macrotermes subhyalinus that was observed during the dry season in a savannah habitat in Nigeria's Gashaka National Park. It was estimated that several hundred thousand termites (probably more than 2.4 kg dry mass) were retrieved. The apparent rarity of driver ant predation on Macrotermes nests may be explained by different habitat requirements, by the fact that these ants mostly forage aboveground, by efficient termite defense behavior and nest architecture that make entry into the nest difficult, and finally by driver ant worker morphology, which differs remarkably from that of subterranean Dorylus species that regularly invade and destroy termite colonies.  相似文献   

19.
Historians of science have only just begun to sample the wealth of different approaches to the study of animal behavior undertaken in the twentieth century. To date, more attention has been given to Lorenzian ethology and American behaviorism than to other work and traditions, but different approaches are equally worthy of the historian’s attention, reflecting not only the broader range of questions that could be asked about animal behavior and the “animal mind” but also the different contexts in which these questions were important. One such approach is that represented by the work of the French zoologist Louis Boutan (1859–1934). This paper explores the intellectual and cultural history of Boutan’s work on animal language and the animal mind, and contextualizes the place of animal behavior studies within late-nineteenth-and early-twentieth-century French biology. I explore the ways in which Boutan addressed the philosophical issue of whether language was necessary for abstract thought and show how he shifted from the idea that animals were endowed with a purely affective language to the notion that of they were capable of “rudimentary” reasoning. I argue that the scientific and broader socio-cultural contexts in which Boutan operated played a role in this transition. Then I show how Boutan’s linguistic and psychological experiments with a gibbon and children provide insights into his conception of “naturalness.” Although Boutan reared his gibbon at home and studied it in the controlled environment of his laboratory, he continued to identify its behavior as “natural.” I specifically demonstrate the importance of the milieu of the French Third Republic in shaping Boutan’s understanding not only of animal intelligence and child education, but also his definition of nature. Finally, I argue that Boutan’s studies on the primate mind provide us with a lens through which we can examine the co-invention of animal and child psychology in early-twentieth-century France.  相似文献   

20.
Animal interactions play an important role in understanding ecological processes. The nature and intensity of these interactions can shape the impacts of organisms on their environment. Because ants and termites, with their high biomass and range of ecological functions, have considerable effects on their environment, the interaction between them is important for ecosystem processes. Although the manner in which ants and termites interact is becoming increasingly well studied, there has been no synthesis to date of the available literature. Here we review and synthesise all existing literature on ant–termite interactions. We infer that ant predation on termites is the most important, most widespread, and most studied type of interaction. Predatory ant species can regulate termite populations and subsequently slow down the decomposition of wood, litter and soil organic matter. As a consequence they also affect plant growth and distribution, nutrient cycling and nutrient availability. Although some ant species are specialised termite predators, there is probably a high level of opportunistic predation by generalist ant species, and hence their impact on ecosystem processes that termites are known to provide varies at the species level. The most fruitful future research direction will be to evaluate the impact of ant–termite predation on broader ecosystem processes. To do this it will be necessary to quantify the efficacy both of particular ant species and of ant communities as a whole in regulating termite populations in different biomes. We envisage that this work will require a combination of methods, including DNA barcoding of ant gut contents along with field observations and exclusion experiments. Such a combined approach is necessary for assessing how this interaction influences entire ecosystems.  相似文献   

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