one of the most important extensions of the capacitated vehicle routing problem (cvrp) is the vehicle routing problem with simultaneous pickup and delivery (vrpspd) where customers require simultaneous delivery and pick-up service. in this paper, we propose an effective ant colony optimization (eaco) which includes insert, swap and 2-opt moves for solving vrpspd that is different with common an...

The Argentine ant, Linepithema humile, was found established in New Zealand in 1990. During summer 2001/2002 the spread of Argentine ants from urban environments into native habitats was investigated. During an initial large-scale survey around the northern cities of Auckland and Whangarei, Argentine ants were observed at 35 of 211 sites. Eight sites in Auckland were subsequently surveyed in gr...

Homing ants have been shown to associate directional information with familiar landmarks. The sight of these local cues might either directly guide the path of the ant or it might activate a landmark-based vector that points towards the goal position. In either case, the ants define their courses within allocentric systems of reference. Here, we show that desert ants, Cataglyphis fortis, forced...

CC-BY 4.0 International license not peer-reviewed) is the author/funder. It is made available under a The copyright holder for this preprint (which was. Abstract A detailed study of the holotype of Sphecomyrma canadensis Wilson 1985 from Canadian amber led to the conclusion that the specimen belongs to a genus here named Boltonimecia gen.nov. not previously described. The taxonomy of stem ants ...

We caught solitary foragers of the Australian Jack Jumper ant, Myrmecia croslandi, and released them in three compass directions at distances of 10 and 15 m from the nest at locations they have never been before. We recorded the head orientation and the movements of ants within a radius of 20 cm from the release point and, in some cases, tracked their subsequent paths with a differential GPS. W...

Ant-fungus associations are well known from attine ants, whose nutrition is based on a symbiosis with basidiomycete fungi. Otherwise, only a few non-nutritional ant-fungus associations have been recorded to date. Here we focus on one of these associations involving Allomerus plant-ants that build galleried structures on their myrmecophytic hosts in order to ambush prey. We show that this associ...

Symbiotic relations are present in the nature and can contribute to success of organisms involved. Endophytic fungi live within leaf tissues without causing any harm host plant, some them be a defense mechanism against attack by leaf-cutting ants. Ants genus Atta known as ants have an obligatory association with fungus Leucoagaricus gongylophorus, cutting pieces leaves bringing back colony fung...

Ants that fall prey to the raids of army ants commonly respond by evacuating their nests. This documented behavior has been underexploited by researchers as an efficient research tool. This study focuses on the evacuation response of the southwestern desert ant Aphaenogaster cockerelli André (Hymenoptera: Formicidae) to the army ant Newamyrmex nigrescens Cresson. It is shown that army ants can ...

Two new myrmecophilous species of the supertribes Clavigeritae and Batrisitae are described from Yunnan, Southwest China: Diartiger jiquanyui sp. nov. associated with Lasius Fabricius ants, Myrmicophila yulong Myrmica Latreille ants. Both compared separated related congeners, images their habitus major diagnostic features provided.

abstract in order to assess the availability of phosphorous (p), different methods have been proposed in the last decades. the results of these methods in soils with various ph, calcium carbonate, organic matter, al and fe oxides and hydroxides and other properties especially in iranian soils can not be used. in addition, knowledge about transformation of p forms is necessary for perception of ...