Rescue specialists in Cataglyphis piliscapa ants: The nature and development of ant first responders

Abstract

Previous research in our laboratories has demonstrated that, within each colony of Cataglyphis piliscapa (formerly C. cursor) ants, only some individuals are capable of performing a complex sequence of behavioral patterns to free trapped nestmates-a sequence that not only is memory-dependent but also is responsive to the particular circumstances of that entrapment and how the rescue operation unfolds. Additionally, this rescue behavior is inherited patrilineally from but a few of the many males that fertilize the eggs of the colony's single queen. Here, we describe three experiments to explore rescue behavior further-namely, whether rescuers are in any way selective about which nestmates they help, how the age of rescuers and the victims that they help affect the quantity and quality of the rescue operation, and when this complex behavior first emerges in an ant's development. Taken together with the previous heritability analysis, these behavioral experiments provide clear evidence that the ability to rescue nestmates in distress should be recognized as a specialization, which together with other specialized tasks in C. piliscapa, contributes to a division of labor that increases the efficiency of the colony as a whole and, thus increases its reproductive success.

Do They Know What They Are Doing? Cognitive Aspects of Rescue Behaviour Directed by Workers of the Red Wood Ant Formica polyctena to Nestmate Victims Entrapped in Artificial Snares

“…This was possible thanks to the application of a novel version of the nestmate rescue test consisting of a confrontation of potential rescuers with a nestmate victim entrapped in an artificial snare. In contrast to earlier studies with the use of the artificial snare bioassay [29,59,61,62,[64][65][66][67][68][69][70][72][73][74][75][76][77], in our study each nestmate victim was bearing on its body not just one, but two wire loops, one placed on its petiole and an additional one placed on its leg. Only the loop on the victim's petiole was acting as a snare, the loop on the leg was not implicated in the victim's entrapment.…”

“…About twenty years ago, Czechowski et al (2002) [28] employed the term "rescue behaviour" in the title and the text of the paper describing rescue behaviour displayed by workers of three ant species (Formica sanguinea, Formica fusca and Formica cinerea) in response to ant victims captured by predatory antlion larvae (Myrmeleon formicarius). This study provided inspiration for further extensive research carried out both in the field and in the laboratory with the use of two main bioassays: antlion larva capture bioassay, during which ant rescue behaviour was elicited in response to an ant captured by an antlion larva [59][60][61][62][63] and artificial snare bioassay, during which ant rescue behaviour was elicited in response to a victim ant entrapped in an artificial snare [29,59,61,62,[64][65][66][67][68][69][70][71][72][73][74][75][76][77].…”

“…Such an artificial snare bioassay has been used in numerous laboratory and field experiments to test a wide range of ant species from the subfamilies Formicinae [29,59,61,62,[64][65][66][67][68][69][70]72,[74][75][76][77], Myrmicinae [59,61,67] and Dolichoderinae [61]. Modified versions of that bioassay consisted of a confrontation of potential rescuers with a victim immobilized by means of duct tape applied to its legs (Odontomachus brunneus, subfamily Ponerinae) [73] and of simultaneous confrontation of potential rescuers with two artificial snares, one empty and one containing a victim, or containing two different victims (Cataglyphis nigra, subfamily Formicinae) [77].…”

“…Such an ability was documented mostly in the results of the experiments carried out with the use of the artificial snare bioassay, including the first study in which this method has been introduced [29]. In these studies, rescue attempts directed precisely to the object responsible for the victim's entrapment were labelled with several similar terms, including such expressions as "precision rescue", "precision rescue behaviour" and "precise rescue behaviour patterns" [19,59,64,65,67,74,102]; "precisely directed rescue behaviour" [29,30,68,102]; "precisely targeted rescue behaviour" [30,66,68,72]; and "precisely tuned rescue behaviour" [80]. Responses to the snare responsible for the entrapment of the victim were also investigated and/or discussed in some other research papers in which these terms were not used [61,62,70,73,75,76], as well as in several review papers [11,19,41,80].…”

Desert Ants Learn to Avoid Pitfall Traps While Foraging

“…Many such species occur in sandy habitats, in which pits dug by pit-building predators as well as other opportunities to get trapped exist [ 42 , 43 , 44 ]. The congeneric species Cataglyphis cursor or C. piliscapa rescue workers when trapped [ 42 , 45 ].…”