The ability of queens and males of most ant species to disperse by flight has fundamentally contributed to the group’s evolutionary and ecological success and is a determining factor to take into account for biogeogr...The ability of queens and males of most ant species to disperse by flight has fundamentally contributed to the group’s evolutionary and ecological success and is a determining factor to take into account for biogeographic studies(Wagner and Liebherr 1992;Peeters and Ito 2001;Helms 2018).展开更多
The present research investigated a segment of the micro-arthropod populations residing within nests of Messor arenarius ants in the Negev Desert of Israel. The total frequencies of micro-arthropods in the chaff of th...The present research investigated a segment of the micro-arthropod populations residing within nests of Messor arenarius ants in the Negev Desert of Israel. The total frequencies of micro-arthropods in the chaff of those ants’ nests were found to be higher than in the surrounding soil of the same nests. Acari (mites) were observed to be more abundant during the spring season, whereas their presence decreased during the summer months. Springtails (Collembola) were found to follow the Acari pattern, commonly found within the nests of those ants during spring but were absent during summer. Psocoptera order inhabiting soil habitats were infrequently encountered during spring, but their prevalence increased significantly during summer, particularly within the chaff of the ants’ nests, suggesting that chaff is their primary food source in the Negev Desert. Our research suggests that shifts in seasonality have important consequences on the distribution of soil invertebrate communities with implications on nutrient cycling.展开更多
This paper systematically studies the movement behavior changes of Camponotus japonicus under one or two leg injuries.Firstly,a linear motion channel matching the size of the ants'legs was designed,and the movemen...This paper systematically studies the movement behavior changes of Camponotus japonicus under one or two leg injuries.Firstly,a linear motion channel matching the size of the ants'legs was designed,and the movements of ants with different leg injuries were captured using high-speed cameras,constructing a comprehensive video dataset of ants'movements with missing legs.Secondly,stable and reliable motion position information for keypoints on the ants'bodies and legs was obtained by utilizing low-annotation biometric keypoint detection technology.Finally,by analyzing the filtered gait data,information about the changes in the step locational points areas,phase differences,and duty factors of the injured ants'remaining legs was obtained.Comparative analysis of the ants'gait characteristics revealed some common adjustment patterns when the ants were in the injured states.Additionally,the study found that the loss of a foreleg had a significant impact on the ants'movement.When two legs were missing,the loss of both legs on the same side had a greater effect on movement,whereas symmetric opposite-side leg loss conditions had a lesser impact.The research will provide an important reference for the subsequent design of gait adjustment algorithms for biomimetic multi-legged robots under damaged conditions.展开更多
Ant colonies self-organize to solve complex problems despite the simplicity of an individual ant＇s brain. Pavement ant Tetramorium caespitum colonies must solve the problem of defending the ter- ritory that they patr...Ant colonies self-organize to solve complex problems despite the simplicity of an individual ant＇s brain. Pavement ant Tetramorium caespitum colonies must solve the problem of defending the ter- ritory that they patrol in search of energetically rich forage. When members of 2 colonies randomly interact at the territory boundary a decision to fight occurs when： 1） there is a mismatch in nest- mate recognition cues and 2） each ant has a recent history of high interaction rates with nestmate ants. Instead of fighting, some ants will decide to recruit more workers from the nest to the fighting location, and in this way a positive feedback mediates the development of colony wide wars. In ants, the monoamines serotonin （5-HT） and octopamine （OA） modulate many behaviors associated with colony organization and in particular behaviors associated with nestmate recognition and ag- gression. In this article, we develop and explore an agent-based model that conceptualizes how in- dividual changes in brain concentrations of 5-HT and OA, paired with a simple threshold-based de- cision rule, can lead to the development of colony wide warfare. Model simulations do lead to the development of warfare with 91% of ants fighting at the end of 1 h. When conducting a sensitivity analysis, we determined that uncertainty in monoamine concentration signal decay influences the behavior of the model more than uncertainty in the decision-making rule or density. We conclude that pavement ant behavior is consistent with the detection of interaction rate through a single timed interval rather than integration of multiple interactions.展开更多
Ants (Formicidae, Hymenoptera) play an important role in seed bank, seedling establishment andplant composition of arid ecosystems. Thus, knowing plant-ant interaction provides useful information formanagers to design...Ants (Formicidae, Hymenoptera) play an important role in seed bank, seedling establishment andplant composition of arid ecosystems. Thus, knowing plant-ant interaction provides useful information formanagers to design restoration and conservation plans. In this study, the roles of desert harvester ants (Messorintermedius and Messor melancholicus) and scavenger ants (Cataglyphis nodus and Lepisiota semenovi) on plantcommunities were investigated in arid ecosystems of southeastern Iran. Two vegetation types weredistinguished in the study area and the nest density of ant species was determined. Furthermore, plantcomposition and soil seed bank were estimated at different distances from the ant nests. Results showed thatthe density of M. intermedius and M. melancholicus nests was higher in dwarf shrub-shrub vegetation type and thedensity of C. nodus and L. semenovi nests was higher in dwarf shrub vegetation type. The harvester and scavengerants had enhanced the seed bank to 55% and 70%, respectively. Therefore, the role of scavenger ants on theplant communities' seed bank was greater than that of harvester ants. Although the scavenger ants were moreinfluential on the annuals and the invasive plant species, the radius impact of the harvester ants on theperennials was greater, i.e., a positive interaction existed between the perennial plants and the harvester ants. C.nodus and L. semenovi played an important role in enhancing the ecosystem's potential for restoration throughestablishment of pioneer species in early stage of succession. The activity of M. intermedius is crucial for thedevelopment and maintenance of climax plant communities in arid ecosystems through assisting the plantspecies' establishment in late stage of succession. It is essential to preserve the diversity of these key ant speciesfor the maintenance and sustainability of shrubs in arid ecosystems.展开更多
Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants...Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community parameters.We described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group scheme.We used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent ranch.Eleven of the 27 recorded species showed significant differences in their abundance and two species were absent at the ranch.While richness and diversity did not reflect these differences,functional groups did.Hot Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the reserve.This study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions.展开更多
Injury is common in nature resulting,for example,from fighting,partial predation,or the wear of body parts.Injury is costly,expressed in impaired performance,failure in competition,and a shorter life span.A survey of ...Injury is common in nature resulting,for example,from fighting,partial predation,or the wear of body parts.Injury is costly,expressed in impaired performance,failure in competition,and a shorter life span.A survey of the literature revealed the frequent occurrence of injury in ants and its various causes.We examined whether leg or antenna injury impacts food-discovery time and reduces the likelihood of reaching food in workers of the desert ant Cataglyphis niger.We examined the search-related consequences of injury in groups of either 4 or 8 workers searching for food in a short arena,a long arena,and a maze.We conducted a small field survey to evaluate the prevalence of injury in the studied population.Finally,we compared the survival rates of injured versus uninjured workers in the laboratory.Injury was common in the field,with almost 9%of the workers collected out of the nest,found to be injured.Injured workers survived shorter than uninjured ones and there was a positive link between injury severity and survival.However,we could not detect an effect of injury on any of the searching-related response variables,neither in the arenas nor in the mazes tested.We suggest that workers that survive such injury are only moderately affected by it.展开更多
Foragers use several senses to locate food,and many animals rely on vision and smell.It is beneficial not to rely on a single sense,which might fail under certain conditions.We examined the contribution of vision and ...Foragers use several senses to locate food,and many animals rely on vision and smell.It is beneficial not to rely on a single sense,which might fail under certain conditions.We examined the contribution of vision and smell to foraging and maze exploration under laboratory conditions using Cataglyphis desert ants as a model.Foraging intensity,measured as the number of workers entering the maze and arriving at the target as well as target arrival time,were greater when food,blue light,or both were offered or presented in contrast to a control.Workers trained to forage for a combined food and light cue elevated their foraging intensity with experience.However,foraging intensity was not higher when using both cues simultaneously than in either one of the two alone.Following training,we split between the two cues and moved either the food or the blue light to the opposite maze corner.This manipulation impaired foraging success by either leading to fewer workers arriving at the target cell(when the light stayed and the food was moved)or to more workers arriving at the opposite target cell,empty of food(when the food stayed and the light was moved).This result indicates that ant workers use both senses when foraging for food and readily associate light with food.展开更多
Rescue behavior is observed when 1 individual provides help to another individual in danger.Most reports of rescue behavior concern ants(Formicidae),in which workers rescue each other from various types of entrapment....Rescue behavior is observed when 1 individual provides help to another individual in danger.Most reports of rescue behavior concern ants(Formicidae),in which workers rescue each other from various types of entrapment.Many of these entrapment situations can be simulated in the laboratory using an entrapment bioassay,in which ants confront a single endangered nest mate entrapped on a sandy arena by means of an artificial snare.Here,we compared numerous characteristics of rescue actions(contact between individuals,digging around the entrapped individual,pulling at its body parts,transport of the sand covering it,and biting the snare entrapping it)in Formica cinerea ants.We performed entrapment tests in the field and in the laboratory,with the latter under varying conditions in terms of the number of ants potentially engaged in rescue actions and the arena substrate(marked or unmarked by ants'pheromones).Rescue actions were more probable and pronounced in the field than in the laboratory,regardless of the type of test.Moreover,different test types in the laboratory yielded inconsistent results and showed noteworthy variability depending on the tested characteristic of rescue.Our results illustrate the specifics of ant rescue actions elicited in the natural setting,which is especially important considering the scarcity of field data.Furthermore,our results underline the challenges related to the comparison of results from different types of entrapment tests reported in the available literature.Additionally,our study shows how animal behavior differs in differing experimental setups used to answer the same questions.展开更多
NP-hard combinational optimization problem is not solved very well until now. One enhanced ants system based on ants system is advanced after analysis of the deficiencies of existing ants systems. Some improvements ar...NP-hard combinational optimization problem is not solved very well until now. One enhanced ants system based on ants system is advanced after analysis of the deficiencies of existing ants systems. Some improvements are made in state transfer rule and local modification rule. Furthermore, the enhanced ants system can solve NP-hard combinational optimization problem with restraints and condition path. The successful application of TSP problem and transportation net problem indicates that the proposed system has stronger function and higher efficiency than the original system.展开更多
Beginning with the analysis of the behavior of natural ants, this paper illuminates the principle and method that, by adopting image texture energy as pheromone and finding their way on the track of the pheromone, art...Beginning with the analysis of the behavior of natural ants, this paper illuminates the principle and method that, by adopting image texture energy as pheromone and finding their way on the track of the pheromone, artificial ants have the ability to identify and remember through similar measurement of pheromone. Based on the quantity of experiments, this paper analyzes some factors that influence the ability of artificial ants and draws some conclusions about the law of ant perception.展开更多
We examined the relationship between seasonal livestock grazing (late summer and late winter) and the abundance of two ant species, Dorymyrmex insana and Forelius pruniosus, on three types of plants (mesquite shrubs, ...We examined the relationship between seasonal livestock grazing (late summer and late winter) and the abundance of two ant species, Dorymyrmex insana and Forelius pruniosus, on three types of plants (mesquite shrubs, snakeweed sub-shrubs, and mixed grasses) dominated by black grama (Bouteloua eriopoda). Stocking rates were adjusted to remove 75% of the available forage. Since Chihuahuan Desert grasslands are not in transition to shrublands, the grasses and some herbaceous plants are the only available forage. We hypothesized that neither rainfall nor cattle grazing would affect the abundance of these ants on mesquite (Prosipis glandulosa) or snakeweed (Gutierrezia sarothrae). Linear regressions of monsoon rainfall on mesquite (Prosopis glandulosa) produced an r<sup>2</sup> nearly equal to that with the annual precipitation. Monsoon rainfall on the evergreen sub-shrub, Gutierrezia sarothrae, resulted in June-July rainfall accounting for 47% - 83% of the variation in densities of D. insana on snakeweed. The number of D. insana was more than double the number of F. pruinosus on grasses, mesquite, and snakeweed. There were significant reductions in the abundance of F. pruinosus on the grass in the grazed plots;each year the plots were grazed. There were no significant effects of grazing on the abundance of either of the ant species sampled from G. sarothrae canopies. There were significantly fewer D. insana on mesquite in summer grazed plots than on P. glandulosa in winter grazed and ungrazed plots in the second and third years of grazing. Pre-grazing effects were compromised by the high annual (more than double) precipitation.展开更多
Symbiotic relations are present in the nature and can contribute to the success of the organisms involved. Endophytic fungi live within the leaf tissues without causing any harm to the host plant, and some of them can...Symbiotic relations are present in the nature and can contribute to the success of the organisms involved. Endophytic fungi live within the leaf tissues without causing any harm to the host plant, and some of them can be a defense mechanism against the attack by the leaf-cutting ants. Ants of the genus <em>Atta</em> are known as leaf-cutting ants and have an obligatory association with the fungus <em>Leucoagaricus gongylophorus</em>, cutting pieces of leaves and bringing them back to the colony to the fungus. The present study aimed to find out the endophytic fungi community of an attractive plant (<em>Acalypha wilkesiana</em>) and a less attractive plant (<em>Colocasia esculenta</em>) to the ants <em>Atta sexdens</em>. We found out that the communities are different in quantity and in composition and 73% of the isolated fungi were from <em>A. wilkesiana</em>, which has fungi known as attractive to leaf-cutting ants, such as genus<em> Colletotrichum</em>, <em>Pestalotiopsis</em>, <em>Phomopsis </em>and <em>Xylaria</em>. On the other hand, in <em>C. esculenta</em>, there was found the genus<em> Fusarium</em>, known to be reject by the leaf-cutting ants, and less fungal diversity than in the attractive plant <em>A. wilkesiana</em>. Therefore, our data suggest that attractivity or repelence of a plant to the leaf-cutting ants could be related to presence or ausence of determinated fungi more than the quantity of fungi present in a leaf.展开更多
The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the know...The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.展开更多
The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the know...The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.展开更多
基金funded by the“Departments of Excellence”program of the Italian Ministry for University and Research(MIUR,2018-2022 and MUR,2023-2027).
文摘The ability of queens and males of most ant species to disperse by flight has fundamentally contributed to the group’s evolutionary and ecological success and is a determining factor to take into account for biogeographic studies(Wagner and Liebherr 1992;Peeters and Ito 2001;Helms 2018).
文摘The present research investigated a segment of the micro-arthropod populations residing within nests of Messor arenarius ants in the Negev Desert of Israel. The total frequencies of micro-arthropods in the chaff of those ants’ nests were found to be higher than in the surrounding soil of the same nests. Acari (mites) were observed to be more abundant during the spring season, whereas their presence decreased during the summer months. Springtails (Collembola) were found to follow the Acari pattern, commonly found within the nests of those ants during spring but were absent during summer. Psocoptera order inhabiting soil habitats were infrequently encountered during spring, but their prevalence increased significantly during summer, particularly within the chaff of the ants’ nests, suggesting that chaff is their primary food source in the Negev Desert. Our research suggests that shifts in seasonality have important consequences on the distribution of soil invertebrate communities with implications on nutrient cycling.
基金supported by Natural Science Foundation of Tianjin Municipality under Grant(No.23JCYBJC01670).
文摘This paper systematically studies the movement behavior changes of Camponotus japonicus under one or two leg injuries.Firstly,a linear motion channel matching the size of the ants'legs was designed,and the movements of ants with different leg injuries were captured using high-speed cameras,constructing a comprehensive video dataset of ants'movements with missing legs.Secondly,stable and reliable motion position information for keypoints on the ants'bodies and legs was obtained by utilizing low-annotation biometric keypoint detection technology.Finally,by analyzing the filtered gait data,information about the changes in the step locational points areas,phase differences,and duty factors of the injured ants'remaining legs was obtained.Comparative analysis of the ants'gait characteristics revealed some common adjustment patterns when the ants were in the injured states.Additionally,the study found that the loss of a foreleg had a significant impact on the ants'movement.When two legs were missing,the loss of both legs on the same side had a greater effect on movement,whereas symmetric opposite-side leg loss conditions had a lesser impact.The research will provide an important reference for the subsequent design of gait adjustment algorithms for biomimetic multi-legged robots under damaged conditions.
文摘Ant colonies self-organize to solve complex problems despite the simplicity of an individual ant＇s brain. Pavement ant Tetramorium caespitum colonies must solve the problem of defending the ter- ritory that they patrol in search of energetically rich forage. When members of 2 colonies randomly interact at the territory boundary a decision to fight occurs when： 1） there is a mismatch in nest- mate recognition cues and 2） each ant has a recent history of high interaction rates with nestmate ants. Instead of fighting, some ants will decide to recruit more workers from the nest to the fighting location, and in this way a positive feedback mediates the development of colony wide wars. In ants, the monoamines serotonin （5-HT） and octopamine （OA） modulate many behaviors associated with colony organization and in particular behaviors associated with nestmate recognition and ag- gression. In this article, we develop and explore an agent-based model that conceptualizes how in- dividual changes in brain concentrations of 5-HT and OA, paired with a simple threshold-based de- cision rule, can lead to the development of colony wide warfare. Model simulations do lead to the development of warfare with 91% of ants fighting at the end of 1 h. When conducting a sensitivity analysis, we determined that uncertainty in monoamine concentration signal decay influences the behavior of the model more than uncertainty in the decision-making rule or density. We conclude that pavement ant behavior is consistent with the detection of interaction rate through a single timed interval rather than integration of multiple interactions.
文摘Ants (Formicidae, Hymenoptera) play an important role in seed bank, seedling establishment andplant composition of arid ecosystems. Thus, knowing plant-ant interaction provides useful information formanagers to design restoration and conservation plans. In this study, the roles of desert harvester ants (Messorintermedius and Messor melancholicus) and scavenger ants (Cataglyphis nodus and Lepisiota semenovi) on plantcommunities were investigated in arid ecosystems of southeastern Iran. Two vegetation types weredistinguished in the study area and the nest density of ant species was determined. Furthermore, plantcomposition and soil seed bank were estimated at different distances from the ant nests. Results showed thatthe density of M. intermedius and M. melancholicus nests was higher in dwarf shrub-shrub vegetation type and thedensity of C. nodus and L. semenovi nests was higher in dwarf shrub vegetation type. The harvester and scavengerants had enhanced the seed bank to 55% and 70%, respectively. Therefore, the role of scavenger ants on theplant communities' seed bank was greater than that of harvester ants. Although the scavenger ants were moreinfluential on the annuals and the invasive plant species, the radius impact of the harvester ants on theperennials was greater, i.e., a positive interaction existed between the perennial plants and the harvester ants. C.nodus and L. semenovi played an important role in enhancing the ecosystem's potential for restoration throughestablishment of pioneer species in early stage of succession. The activity of M. intermedius is crucial for thedevelopment and maintenance of climax plant communities in arid ecosystems through assisting the plantspecies' establishment in late stage of succession. It is essential to preserve the diversity of these key ant speciesfor the maintenance and sustainability of shrubs in arid ecosystems.
基金partially funded by a grant from the National Council of Research (Argentina) Number 4678 for the project"Insect Biodiversity of the Monte"
文摘Livestock ranching is one of the main productive activities in arid regions of the world.Grazing produces changes in animal as well as plant communities(e.g.richness,abundance and species dominance relationships).Ants are good biological indicators due to the environmental fidelity of some of their community parameters.We described the functional structure of the ant community in the central Monte of Mendoza,Argentina,and examined the effect of grazing using richness,diversity and the functional group scheme.We used pitfall traps to sample ants at a reserve with 30-year cattle exclusion and at an adjacent ranch.Eleven of the 27 recorded species showed significant differences in their abundance and two species were absent at the ranch.While richness and diversity did not reflect these differences,functional groups did.Hot Climate Specialists were more abundant at the ranch while Cryptic Species and Generalized Myrmicinae increased at the reserve.This study supports the utility of the functional group scheme to study the effects of grazing disturbance in ant communities of arid regions.
文摘Injury is common in nature resulting,for example,from fighting,partial predation,or the wear of body parts.Injury is costly,expressed in impaired performance,failure in competition,and a shorter life span.A survey of the literature revealed the frequent occurrence of injury in ants and its various causes.We examined whether leg or antenna injury impacts food-discovery time and reduces the likelihood of reaching food in workers of the desert ant Cataglyphis niger.We examined the search-related consequences of injury in groups of either 4 or 8 workers searching for food in a short arena,a long arena,and a maze.We conducted a small field survey to evaluate the prevalence of injury in the studied population.Finally,we compared the survival rates of injured versus uninjured workers in the laboratory.Injury was common in the field,with almost 9%of the workers collected out of the nest,found to be injured.Injured workers survived shorter than uninjured ones and there was a positive link between injury severity and survival.However,we could not detect an effect of injury on any of the searching-related response variables,neither in the arenas nor in the mazes tested.We suggest that workers that survive such injury are only moderately affected by it.
基金We thank the German Research Foundation for funding this research project(DFG,grant no.FO 298/31-1).
文摘Foragers use several senses to locate food,and many animals rely on vision and smell.It is beneficial not to rely on a single sense,which might fail under certain conditions.We examined the contribution of vision and smell to foraging and maze exploration under laboratory conditions using Cataglyphis desert ants as a model.Foraging intensity,measured as the number of workers entering the maze and arriving at the target as well as target arrival time,were greater when food,blue light,or both were offered or presented in contrast to a control.Workers trained to forage for a combined food and light cue elevated their foraging intensity with experience.However,foraging intensity was not higher when using both cues simultaneously than in either one of the two alone.Following training,we split between the two cues and moved either the food or the blue light to the opposite maze corner.This manipulation impaired foraging success by either leading to fewer workers arriving at the target cell(when the light stayed and the food was moved)or to more workers arriving at the opposite target cell,empty of food(when the food stayed and the light was moved).This result indicates that ant workers use both senses when foraging for food and readily associate light with food.
基金The study was funded by the National Science Centre,Poland[grant PRELUDIUM number 2018/31/N/NZ8/02312].
文摘Rescue behavior is observed when 1 individual provides help to another individual in danger.Most reports of rescue behavior concern ants(Formicidae),in which workers rescue each other from various types of entrapment.Many of these entrapment situations can be simulated in the laboratory using an entrapment bioassay,in which ants confront a single endangered nest mate entrapped on a sandy arena by means of an artificial snare.Here,we compared numerous characteristics of rescue actions(contact between individuals,digging around the entrapped individual,pulling at its body parts,transport of the sand covering it,and biting the snare entrapping it)in Formica cinerea ants.We performed entrapment tests in the field and in the laboratory,with the latter under varying conditions in terms of the number of ants potentially engaged in rescue actions and the arena substrate(marked or unmarked by ants'pheromones).Rescue actions were more probable and pronounced in the field than in the laboratory,regardless of the type of test.Moreover,different test types in the laboratory yielded inconsistent results and showed noteworthy variability depending on the tested characteristic of rescue.Our results illustrate the specifics of ant rescue actions elicited in the natural setting,which is especially important considering the scarcity of field data.Furthermore,our results underline the challenges related to the comparison of results from different types of entrapment tests reported in the available literature.Additionally,our study shows how animal behavior differs in differing experimental setups used to answer the same questions.
基金This project was supported by the National Natural Science Foundation of Shangdong Province (Y98F12093) .
文摘NP-hard combinational optimization problem is not solved very well until now. One enhanced ants system based on ants system is advanced after analysis of the deficiencies of existing ants systems. Some improvements are made in state transfer rule and local modification rule. Furthermore, the enhanced ants system can solve NP-hard combinational optimization problem with restraints and condition path. The successful application of TSP problem and transportation net problem indicates that the proposed system has stronger function and higher efficiency than the original system.
基金Founded by the National Science Foundation of China (No.42071094) .
文摘Beginning with the analysis of the behavior of natural ants, this paper illuminates the principle and method that, by adopting image texture energy as pheromone and finding their way on the track of the pheromone, artificial ants have the ability to identify and remember through similar measurement of pheromone. Based on the quantity of experiments, this paper analyzes some factors that influence the ability of artificial ants and draws some conclusions about the law of ant perception.
文摘We examined the relationship between seasonal livestock grazing (late summer and late winter) and the abundance of two ant species, Dorymyrmex insana and Forelius pruniosus, on three types of plants (mesquite shrubs, snakeweed sub-shrubs, and mixed grasses) dominated by black grama (Bouteloua eriopoda). Stocking rates were adjusted to remove 75% of the available forage. Since Chihuahuan Desert grasslands are not in transition to shrublands, the grasses and some herbaceous plants are the only available forage. We hypothesized that neither rainfall nor cattle grazing would affect the abundance of these ants on mesquite (Prosipis glandulosa) or snakeweed (Gutierrezia sarothrae). Linear regressions of monsoon rainfall on mesquite (Prosopis glandulosa) produced an r<sup>2</sup> nearly equal to that with the annual precipitation. Monsoon rainfall on the evergreen sub-shrub, Gutierrezia sarothrae, resulted in June-July rainfall accounting for 47% - 83% of the variation in densities of D. insana on snakeweed. The number of D. insana was more than double the number of F. pruinosus on grasses, mesquite, and snakeweed. There were significant reductions in the abundance of F. pruinosus on the grass in the grazed plots;each year the plots were grazed. There were no significant effects of grazing on the abundance of either of the ant species sampled from G. sarothrae canopies. There were significantly fewer D. insana on mesquite in summer grazed plots than on P. glandulosa in winter grazed and ungrazed plots in the second and third years of grazing. Pre-grazing effects were compromised by the high annual (more than double) precipitation.
文摘Symbiotic relations are present in the nature and can contribute to the success of the organisms involved. Endophytic fungi live within the leaf tissues without causing any harm to the host plant, and some of them can be a defense mechanism against the attack by the leaf-cutting ants. Ants of the genus <em>Atta</em> are known as leaf-cutting ants and have an obligatory association with the fungus <em>Leucoagaricus gongylophorus</em>, cutting pieces of leaves and bringing them back to the colony to the fungus. The present study aimed to find out the endophytic fungi community of an attractive plant (<em>Acalypha wilkesiana</em>) and a less attractive plant (<em>Colocasia esculenta</em>) to the ants <em>Atta sexdens</em>. We found out that the communities are different in quantity and in composition and 73% of the isolated fungi were from <em>A. wilkesiana</em>, which has fungi known as attractive to leaf-cutting ants, such as genus<em> Colletotrichum</em>, <em>Pestalotiopsis</em>, <em>Phomopsis </em>and <em>Xylaria</em>. On the other hand, in <em>C. esculenta</em>, there was found the genus<em> Fusarium</em>, known to be reject by the leaf-cutting ants, and less fungal diversity than in the attractive plant <em>A. wilkesiana</em>. Therefore, our data suggest that attractivity or repelence of a plant to the leaf-cutting ants could be related to presence or ausence of determinated fungi more than the quantity of fungi present in a leaf.
文摘The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.
文摘The ants are one of the mega diverse insets found in all terrestrial environments, and occur in great diversity, richness and abundance, acting at all trophic levels. The present study was conducted to verify the knowledge of ant fauna at Caxiuanã National forest. All available ant literature and some collection in Caxiuanã were compiled and analyzed in EXCEL program. Caxiuanã is one Brazilian Amazonia forest that has good biological conservation. A total of 197 species belonging to 52 genera of the nine subfamilies are present in Caxiuanã. Many studies need to be done in this place to understand the ant community pattern to give base for other studies and proposal for use, management and conservation of this interesting Amazonia place.
