Ant Pheromone Research Articles

Regional Route Maintenance Protocol Based on Local Pheromone Diffusion for Mobile Ad Hoc Networks

Route maintenance protocol has a tradeoff between the amount of control overhead and the provision of useful alternative paths. To break through this tradeoff, we consider a bio-inspired approach based on the natural phenomena of ant pheromone. The pheromone is accumulated on the shortest path between the nest and the food, and then diffused into its vicinity over time. Thus, the ants can find another route along this locally diffused pheromone when the shortest path in use is blocked. Based on this local pheromone diffusion and rerouting behavior, we propose a new route maintenance protocol for mobile ad hoc networks. First, pheromones (i.e., routing information) are locally diffused around the shortest path between the source and the destination (i) by overhearing at the one-hop neighbors from the shortest path and (ii) by sharing the overheard pheromone information among the one-hop neighbors. Thereafter, a probabilistic path exploration is executed within the one-hop region based on the locally diffused pheromone and so useful alternative paths around the shortest path are discovered. Through intensive simulations, we verify that the proposed regional route maintenance protocol outperforms the conventional routing protocols in terms of disruption frequency, delivery ratio, delay, and jitter, while reducing the control overhead.

Alarm Pheromone Composition and Behavioral Activity in Fungus-Growing Ants

Chemical communication is a dominant method of communication throughout the animal kingdom and can be especially important in group-living animals in which communicating threats, either from predation or other dangers, can have large impacts on group survival. Social insects, in particular, have evolved a number of pheromonal compounds specifically to signal alarm. There is predicted to be little selection for interspecific variation in alarm cues because individuals may benefit from recognizing interspecific as well as conspecific cues and, consequently, alarm cues are not normally thought to be used for species or nestmate recognition. Here, we examine the composition of the alarm pheromones of seven species of fungus-growing ants (Attini), including both basal and derived species and examine the behavioral responses to alarm pheromone of Acromyrmex leaf-cutting ants, the sister genus to the highly studied Atta leaf-cutting ants. We find surprisingly high interspecific variation in alarm pheromone composition across the attine phylogeny. Interestingly, the active component of the alarm pheromone was different between the two leaf-cutting ant genera. Furthermore, in contrast to previous studies on Atta, we found no differences among morphological castes in their responses to alarm pheromone in Acromyrmex but we did find differences in responses among putative age classes. The results suggest that the evolution of alarm communication and signaling within social insect clades can be unexpectedly complex and that further work is warranted to understand whether the evolution of different alarm pheromone compounds is adaptive.

Decentralised trust-management inspired by ant pheromones

Computational trust is increasingly utilised to select interaction partners in open technical systems consisting of heterogeneous, autonomous agents. Current approaches rely on centralised elements for managing trust ratings (i.e. control and provide access to aggregated ratings). Consider a grid computing application as illustrating example: agents share their computing resources and cooperate in terms of processing computing jobs. These agents are free to join and leave, and they decide on their own with whom to interact. The impact of malicious or uncooperative agents can be countered by only cooperating with agents that have shown to be benevolent: trust relationships are established. Typically, this requires a centralised data-base storing information about past interactions and their outcome. In this article, we propose a novel, decentralised trust mechanism inspired by the nestmate recognition system in ants. More precisely, the concept of recognition pheromones, which stick to the agents and cannot be removed or counterfeit, is turned into algorithmic logic and interaction protocols. We demonstrate the potential benefit by using simulations of the grid scenario.

Decentralised trust-management inspired by ant pheromones

Decentralised trust-management inspired by ant pheromones

Stereoselective Synthesis and Retentive Trapping of α-Chiral Secondary Alkyllithiums Leading to Stereodefined α,β-Dimethyl Carboxylic Esters.

The treatment of α-chiral secondary alkyl iodides with tBuLi at -100 °C leads to the corresponding secondary alkyllithiums with high retention of configuration. Subsequent quenching with various electrophiles such as Bu2 S2 , DMF, MeOB(OR)2 , or Et2 CO provides the desired products with retention of configuration. Furthermore, a transmetalation with CuBr⋅P(OEt)3 also allows retentive trapping with acid chlorides and ethylene oxide. The quenching of the resulting alkyllithiums with ClCO2 Et furnishes stereoselectively syn- and anti-ethyl-2,3-dimethyl ester carboxylates (d.r.>94 %). Related esters bearing three adjacent stereo-controlled centers (stereotriads) have also been prepared. This method has been applied to the synthesis of the ant pheromone (±)-lasiol in 26 % overall yield (four steps) with d.r.=97:3 starting from commercially available cis-2,3-epoxybutane.

Automated tracking approach with ant colonies for different cell population density distribution

Visual tracking of cells has many challenges due to complex situations such as varying cell population densities, intricate motion patterns and sophisticated interactions with other cells. This paper focuses on an efficient and effective ant-based method with working modes updated to track multiple cells over varying densities in the presence of occlusion or clustering situations. To overcome these challenges, the proposed Ant Colony Optimization (ACO) algorithm models two types of ant working modes, namely, cooperation mode and interactive competition mode, whereas the classical ACO algorithms use only one type of mode which performs poor in clutter situations. Moreover, mode update strategies based on ant colony pheromone is used to adjust pheromone field to obtain accurate state vector of cells. Experimental results demonstrate that the proposed method robustly tracks multiple cells in various scenarios. The averaged LSR, LTR and FTR of our method can be only 1.43, 1.71 and 1.37 %, respectively. Our experimental results also show that our tracking method is competitive with state-of-the-art multi-cell tracking methods.

Honey Bees Avoiding Ant Harassment at Flowers Using Scent Cues.

Pollinators require resources throughout the year to maintain healthy populations. Along the urban-natural interface, floral resource availability may be limited especially when the system experiences extreme drought and fire threats. In such areas, succulents, such as Aloe spp., are commonly planted to serve as functional drought-tolerant, fire-protective landscaping, which can also support pollinator populations. However, access to this resource may be restricted by competition from other floral foragers, including invasive pests. We measured free-foraging honey bee (Apis mellifera L.) visitation rate and visitation duration to aloe flowers with and without Argentine ants (Linepithema humile (Mayr)) in a drought-stressed environment and found that bees actively avoided foraging on the ant-occupied flowers. To determine the mechanisms of avoidance, our subsequent experiments assessed visitation in the absence of ants and compared aloe flowers treated with ant pheromone to unmanipulated flowers lacking ant pheromone. Bees approached all flowers equally, but accepted flowers without ants at a higher rate than flowers with ants. Visitation duration also increased twofold on ant-excluded flowers, which suggests that Argentine ants may limit resource acquisition by bees. Honey bees similarly avoided flowers with Argentine ant pheromone and preferentially visited unmanipulated flowers at threefold higher rate. This study demonstrates that honey bees avoid foraging on floral resources with invasive Argentine ants and that bees use ant odors to avoid ant-occupied flowers. Resource limitation by this invasive pest ant may have serious implication for sustaining healthy pollinator populations at the urban-natural interface.

One-Step Synthesis of Racemic 6-Methyloctan-3-One, an Alarm Pheromone Component of Ants of the Genus Crematogaster

6-Methyloctan-3-one (1) was identified as a component of the alarm pheromone of ants of the genus Crematogaster [1]. Several syntheses of this compound as the racemate and an enantiomer are known [2–6]. However, many of them involve several steps and most are labor-intensive and require costly starting materials. We developed a convenient and effective synthetic pathway for a racemic analog of 1 that was based on our recently proposed regioselective carbonylation of 1-alkenes using Et2Zn and TaCl5 catalyst [7]. The reaction of but-1-ene with Et2Zn in the presence of TaCl5 (Et2Zn–but-1-ene–TaCl5 = 110:100:5; Et2Zn concentration 1.0 mmol/mL in hexane, 20°C, 5 h) formed organozinc compound 2. For this, hexane (20 mL) was cooled to –15°C and treated with but-1-ene (2.25 ml, 20 mmol) cooled to –30°C. Then, the solution was cooled to –15–20°C, treated with Et2Zn (2.25 mL, 22 mmol) and TaCl5 (0.4 g, 1 mmol), heated gradually to room temperature, stirred for 5 h, cooled to –5°C, and treated dropwise with propionylchloride (3, 1.74 mL, 20 mmol) in hexane. All these operations were performed under a dry Ar atmosphere. The resulting reaction mixture was stirred for 2 h and treated with aqueous HCl solution (10%). The resulting 1 was extracted by Et2O (3 50 mL). The extracts were dried over anhydrous MgSO4. The solvent was distilled off. The residue was chromatographed (SiO2, hexane) to afford 1 (2.69 g, 99% pure) in 95% yield based on 3 (Scheme 1). The structure of 1 was proven using IR, PMR, and 13C NMR spectral methods and GC-MS in addition to comparison with an authentic sample [6].

Arquitectura FPGA para Simulación de Aprovisionamiento de Alimentos en Colonias de Hormigas Artificiales

Este artículo presenta algunos resultados en relación con el diseño y la implementación de una arquitectura que soporta una plataforma experimental para simular el proceso de alimentación de las colonias de hormigas. Los algoritmos Ant-system y Ant-Cycle modelan el comportamiento de las hormigas. La plataforma permite cambiar parámetros como la cantidad y la velocidad de las hormigas, la cantidad y ubicación de los alimentos y el radio y la frecuencia de difusión de la feromona de las hormigas. Estos parámetros se visualizan a través de una interfaz VGA. La implementación de hardware se lleva a cabo sobre tecnología FPGA de Xilinx©. La teoría detrás de este diseño considera que los comportamientos complejos pueden surgir de sistemas con una estructura simple . Este trabajo se enfrenta a la pregunta acerca de la complejidad global emergente de un sistema cuya complejidad estructural es mínima o inexistente.

Isolation and structure elucidation of a possible ant trail pheromone, from epothilone B producing fermentations of Sorangium cellulosum

Sorangium cellulosum is a myxobacteria producing epothilone B. During the development of the process to purify epothilone B from fermentation of Sorangium cellulosum we identified a possible ant trail pheromone. The initial detection, isolation and structure elucidation of S-3,4-dihydro-8-hydroxy-3,5,7-trimethylisocoumarin will be presented as well as literature regarding its biosignificance.

Synthetic pheromones as a management technique - dispensers reduce Linepithema humile activity in a commercial vineyard.

Invasive ants, such as the Argentine ant, have often been reported to facilitate honeydew-producing hemipteran pests such as mealybugs, which can be vectors of plant pathogens. Synthetic pheromones may offer a target-specific method to control such ants and consequently lower the abundance of honeydew-producing pests. Here we report the results of a trial to suppress Argentine ants in grapevines using ant pheromone dispensers. Compared with untreated controls, we observed a significant drop in Argentine ant activity on the ground, irrespective of whether pheromone dispensers were placed at ground level, within the canopy or in both locations. Ant counts in the canopy confirmed that Argentine ant abundance was reduced under the influence of the pheromone dispenser placed at ground level compared with untreated controls. However, placing dispensers only in the canopy did not reduce the numbers of ants within the canopy compared with untreated controls. Our results showed that pheromone dispensers can significantly reduce Argentine ant foraging in grapevines if they are positioned appropriately. This technique could potentially reduce the abundance of associated mealybugs and potentially attendant virus vectoring areawide.

Comparative responses of four Pseudacteon phorid fly species to host fire ant alarm pheromone and analogs

Several species of Pseudacteon phorid flies, including Pseudacteon cultellatus, P. curvatus, P. obtusus, and P. tricuspis, have been introduced in the southern United States for biological control of imported fire ants, Solenopsis spp. Previous studies showed that Pseudacteon flies use the alarm pheromone and venom alkaloids of fire ants to locate host ant workers. A recent study by our group demonstrated attraction of one of the species, P. tricuspis, to certain alkylpyrazine analogs of fire ant alarm pheromone. If effective, alkylpyrazine analogs of fire ant alarm pheromone may provide cost-efficient alternatives as phorid fly attractants. To test the hypothesis that other phorid fly species are attracted to alkylpyrazine analogs of fire ant alarm pheromone, we compared electroantennogram (EAG) and behavioral responses of four Pseudacteon species, P. cultellatus, P. curvatus, P. obtusus, and P. tricuspis, to the commercially available alarm pheromone isomer (2-ethyl-3,6(or 5)-dimethyl pyrazine) and six structurally related alkylpyrazine analogs at physiologically relevant doses (ranging from picogram to 10 µg). The alarm pheromone isomer and two analogs, 2,3-diethyl-5-methyl pyrazine and 2 ethyl-3,5 + 6 methyl pyrazine, elicited the strongest EAG activity in all four species at all tested doses. Results from four-choice olfactometer bioassays testing the above three EAG-active compounds showed that all four species were strongly attracted to the alarm pheromone isomer at doses ranging from 0.001 to 1 µg. The flies also showed significant attraction to the two analogs (2,3-diethyl-5-methyl pyrazine and 2 ethyl-3,5 + 6 methyl pyrazine) compared to the solvent control but not as strong as the attraction elicited by the alarm pheromone isomer. These results confirm that multiple species of phorid flies use fire ant alarm pheromone as a host location cue. However, the flies are not strongly attracted to the tested alkylpyrazine analogs of the alarm pheromone.

(3S,5R)-6-(benzyloxy)-3-methylhexane-1,5-diol in the synthesis of insect pheromones with methyl-branched carbon chain and of amphidinolide L C 7 –C 14 fragment

New building block (3S,5R)-6-(benzyloxy)-3-methylhexane-1,5-diol was obtained, and based thereon new formal syntheses of (Z)-trogodermal, a component of the sex pheromone of smaller tea tortrix and of the alarm pheromone of ants of genus Crematogaster were suggested. A new synthetic protocol for (3S)-5-methyl-5-oxopentyl acetate and (3S)-5-(benzyloxy)-3-methylpentanal, convenient building blocks for insect pheromones designing was developed. A new simple and efficient asymmetric synthesis of C7–C14 fragment of the cytotoxic macrolactone amphidinolide L was carried out.

Adaptive Clustering based Dynamic Routing of Wireless Sensor Networks via Generalized Ant Colony Optimization

Wireless sensor networks (WSNs) use battery-powered sensor nodes for sensing, thus the energy efficiency is critical to extend the lifespan. The performance depends on the trade-off among energy consumption, latency and reliability. Data aggregation is a fundamental approach to eliminate redundancy and minimize transmission cost so as to save energy. Dynamic clustering based routing is proposed to achieve good performance via adaptive algorithms. The generalized Ant Colony Optimization (ACO) is applied to increase the reliable lifespan of sensor nodes with energy constraints. Each sensor node is modeled as an artificial ant and dynamic routing is modeled as ant foraging. The ant pheromone is released when an energy efficient channel from the source to sink is secured. Route discovery, data aggregation and information loss are modeled as the processes of pheromone diffusion, accumulation and evaporation. Each sensor node estimates the residual energy and dynamically calculates probabilities to select an optimal channel to extend the lifespan of WSNs.

Parallel Ant System Based on OpenMP

To overcome the limitation of precocity and stagnation in classical ant colony algorithm, this article presents a Parallel Ant System Based on OpenMP. The ant colony is divided into three children ant colonies according to the characteristics of natural ant colony multi-group and pheromone updating features of ant colony algorithm. By Open Multi-Processing parallel programming idea, the parallel and cooperating optimization of children ant colonies was obtained. It organically combines local search and global search, makes full use of computing power of multi-core CPU, and improves the efficiency significantly. Contrastive experiments show that the algorithm has a better capability of global optimization than traditional ant colony algorithm.

Enantioselective cyclopropanation of carboxylic esters with alkyl magnesium bromides in the presence of titanium(IV) (4R,5R)-TADDOLates

The reaction of isopropyl 4-chlorobutyrate with 3 equiv of n-BuMgBr in the presence of 1 equiv of titanium(IV) (4R,5R)-TADDOLate in diethyl ether led to the formation of (1S,2S)-(3-chloropropyl)-2-ethylcyclopropanol in 55–70% yield and 55–65% ee. The reaction was performed in the presence of 20 mol % of the catalyst without significant loss in yield and enantioselectivity when solutions of the carboxylic ester and the Grignard reagent were added simultaneously at an equal rate to a refluxing solution of the titanium catalyst in ether. The cyclopropanation of isopropyl propionate under the same conditions gave (1S,2S)-1-ethyl-2-propylcyclopropanol in 50% yield and 65% ee. Its absolute configuration was determined by chemical correlation through acid-catalyzed isomerization to enantiomerically enriched (R)-(−)-4-methyl-3-heptanone, known as a minor component of the trail pheromone of ant Aphaenogaster albisetosus and enantiomer of the alarm pheromone of leaf-cutting ants Atta texana.

The Application of Ant Colony Optimization in Wireless Sensor Network Routing

The paper proposes wireless sensor clustering routing protocol based on ant colony algorithm(ACO). The method firstly uses the network self-topology to get a stable cluster structure based on modularity clustering algorithm; secondly make a new cluster-head selection function according to each cluster node residual energy and the distribution of cluster node; then we propose inter-cluster multi-hop routing algorithm based on ant colony optimization, which in order to balance the energy between consumption on the transmission path and residual one of cluster-head node, developing new ant transmission probability and pheromone updating strategy, we verify the validity of algorithm through simulation.

Towards Believable Resource Gathering Behaviours in Real-time Strategy Games with a Memetic Ant Colony System

In this paper, the resource gathering problem in real-time strategy (RTS) games, is modeled as a path-finding problem where game agents responsible for gathering resources, also known as harvesters, are only equipped with the knowledge of its immediate sur- roundings and must gather knowledge about the dynamics of the navigation graph that it resides on by sharing information and cooperating with other agents in the game environment. This paper proposed the conceptual modeling of a memetic ant colony system (MACS) for believable resource gathering in RTS games. In the proposed MACS, the harvester's path-finding and resource gathering knowledge captured are extracted and represented as memes, which are internally encoded as state transition rules (mem- otype), and externally expressed as ant pheromone on the graph edge (sociotype). Through the inter-play between the memetic evolution and ant colony, harvesters as memetic automatons spawned from an ant colony are able to acquire increasing level of capability in exploring complex dynamic game environment and gathering resources in an adaptive manner, producing consistent and impressive resource gathering behaviors.

MPE 2 S: Multi-paths and Erasure Encoding Based Reliable Transmission Strategy for Wireless Sensor Networks

摘要: 传输可靠性是衡量无线传感器(Wireless sensor networks, WSN)网络性能的一个重要指标. 针对节点故障会影响网络传输稳定性和可靠性的问题, 提出了基于多路径纠删编码的 无线传感器网络可靠传输策略(Multi-paths and erasure encoding strategy, MPE2S). 根据反映链路质量的最优最差蚂蚁系统的信息素归一化值, 在相邻等级节点间建立多条互不交叉的传输路径, 将源数据包经纠删编码的 数据片沿多条路径分配和传输以实现负载均衡和故障容错. 理论分析和仿真结果表明,MPE2S具有较高数据包接收率、数据准确率和能效性, 体现了良好的故障容错性、数据传输稳定性和可靠性. 关键词: 无线传感器网络 / 可靠传输 / 故障容错 / 多路径路由 / 纠删编码

Surface lipids of queen-laid eggs do not regulate queen production in a fission-performing ant

In animal societies, most collective and individual decision making depends on the presence of reproductive individuals. The efficient transmission of information among reproductive and non-reproductive individuals is therefore a determinant of colony organization. In social insects, the presence of a queen modulates multiple colonial activities. In many species, it negatively affects worker reproduction and the development of diploid larvae into future queens. The queen mostly signals her presence through pheromone emission, but the means by which these chemicals are distributed in the colony are still unclear. In several ant species, queen-laid eggs are the vehicle of the queen signal. The aim of this study was to investigate whether queen-laid eggs of the ant Aphaenogaster senilis possess queen-specific cuticular hydrocarbons and/or Dufour or poison gland compounds, and whether the presence of eggs inhibited larval development into queens. Our results show that the queen- and worker-laid eggs shared cuticular and Dufour hydrocarbons with the adults; however, their poison gland compounds were not similar. Queen-laid eggs had more dimethylalkanes and possessed a queen-specific mixture of cuticular hydrocarbons composed of 3,11 + 3,9 + 3,7-dimethylnonacosane, in higher proportions than did worker-laid eggs. Even though the queen-laid eggs were biochemically similar to the queen, their addition to experimentally queenless groups did not prevent the development of new queens. More studies are needed on the means by which queen ant pheromones are transmitted in the colony, and how these mechanisms correlates with life history traits.