Intraspecific nestmate recognition in two parabiotic ant species: acquired recognition cues and low inter-colony discrimination

Abstract

Parabiotic ants-ants that share their nest with another ant species-need to tolerate not only conspecific nestmates, but also nestmates of a foreign species. The parabiotic ants Camponotus rufifemur and Crematogaster modiglianii display high interspecific tolerance, which exceeds their respective partner colony and extends to alien colonies of the partner species. The tolerance appears to be related to unusual cuticular substances in both species. Both species possess hydrocarbons of unusually high chain lengths. In addition, Cr. modiglianii carries high quantities of hereto unknown compounds on its cuticle. These unusual features of the cuticular profiles may affect nestmate recognition within both respective species as well. In the present study, we therefore examined inter-colony discrimination within the two parabiotic species in relation to chemical differentiation. Cr. modiglianii was highly aggressive against workers from alien conspecific colonies in experimental confrontations. In spite of high inter-colony variation in the unknown compounds, however, Cr. modiglianii failed to differentiate between intracolonial and allocolonial unknown compounds. Instead, the cuticular hydrocarbons functioned as recognition cues despite low variation across colonies. Moreover, inter-colony aggression within Cr. modiglianii was significantly influenced by the presence of two methylbranched alkenes acquired from its Ca. rufifemur partner. Ca. rufifemur occurs in two varieties ('red' and 'black') with almost no overlap in their cuticular hydrocarbons. Workers of this species showed low aggression against conspecifics from foreign colonies of the same variety, but attacked workers from the respective other variety. The low inter-colony discrimination within a variety may be related to low chemical differentiation between the colonies. Ca. rufifemur majors elicited significantly more intercolony aggression than medium-sized workers. This may be explained by the density of recognition cues: majors carried significantly higher quantities of cuticular hydrocarbons per body surface.

An apparent mutualism between Afrotropical ant species sharing the same nest

“…Our results confirmed that parabiotic partners might associate with each other despite having distinct nestmate recognition cues (Orivel and Dejean 1997;Menzel et al 2008a;Menzel et al 2009;Emery and Tsutsui 2013) (Figs. 3 and 4).…”

“…Other associations are less strict, as a partner might also tolerate other colonies of the partner (Menzel et al 2008b). In contrast with most social insect parasites that mimic the odor of their host to get accepted, parabiotic ants succeed to associate even when they each have distinct chemical cuticular profiles (Orivel and Dejean 1997;Menzel et al 2008a;Menzel et al 2009). It is suggested that parabiotic ants are able to recognize the chemical profile of the partner using a learning process which leads to colony-or species-specific tolerance (Orivel and Dejean 1997).…”

Cuticular Lipids as a Cross-Talk among Ants, Plants and Butterflies

“…To assess the identity, each member of the colony inspects by antennae the hydrocarbon patterns of other workers and compares it to its own [82], which therefore functions as a template [13,83,84]. Nestmates are then disregarded, whereas the encounter with an intruder or a conspecific causes an antagonistic behavior [85,86]. …”

A Formica fusca és Camponotus vagus hangyafajok koegzisztenciájának formái és feltételei erdőssztyepp élőhelyeken

“…A parabiózis sok tekintetben különbözik az eddig tárgyalt asszociációktól, hisz ez a kapcsolat mindkét társuló fél számára kedvező, mindkét fél előnyhöz jut a kapcsolat révén. Egyik legismertebb példa a Camponotus rufifemur Emery, 1900 és Crematogaster modigliani Emery, 1900 esete, ahol a nagyobb méretű és agresszívabb Camponotus biztosítja a közösen használt fészek védelmét, illetve a felfedezett táplálék védelmét az idegen kompetítorokkal szemben, míg a Crematogaster sokkal hatékonyabb a táplálékforrások felfedezésében és nyomjelzéseit követve a Camponotus dolgozók is előnyhöz jutnak (Menzel et al 2008;Menzel et al 2009;Menzel és Blüthgen 2010;Menzel et al 2011). A parabiotikus kapcsolatban álló kolóniák dolgozói között a trofallaxis is gyakori jelenség, a békés együttélés és a kölcsönös előny egyértelműen mutualista kapcsolatot feltételez (Hölldobler és Wilson 1990;Orivel et al 1997;.…”