At the brink of supercoloniality: genetic, behavioral, and chemical assessments of population structure of the desert ant Cataglyphis niger

Abstract

† These authors have contributed equally to this work.The nesting habits of ants play an important role in structuring ant populations. They vary from monodomy, a colony occupies a single nest, via polydomy, a colony occupies multiple adjacent nests, to supercoloniality, a colony spans over large territories comprising dozen to thousands nests without having any boundaries. The population structure of the desert ant Cataglyphis niger, previously considered to form supercolonies, was studied using genetic, chemical, and behavioral tools in plots of 50 × 50 m at two distinct populations. At the Palmahim site, the plot comprised 15 nests that according to the genetic analysis constituted three colonies. Likewise at the Rishon Leziyyon site 14 nests constituted 5 genetic colonies. In both sites, both chemical analysis and the behavioral (aggression) tests confirmed the colony genetic architecture. The behavioral tests also revealed that aggression between colonies within a population was higher than that exhibited between colonies of different populations, suggesting the occurrence of the "nasty neighbor" phenomenon. In contrast to supercolony structure previously reported in another population of this species, the presently studied populations were composed of polydomous colonies. However, both the genetic and chemical data revealed that the inter-colonial differences between sites were larger than those within site, suggesting some within-site population viscosity. Thus, C. niger exhibits flexible nesting characteristics, from polydomy to supercoloniality, and can be considered at the brink of supercoloniality. We attribute the differences in population structure among sites to the intensity of intraspecific competition.

Determining social and population structures requires multiple approaches: A case study of the desert antCataglyphis israelensis

“…In conclusion, the most probable population structure of C. israelensis along the coastline of Atlit is that of polydomy, with each colony consisting in one main nest, in which the single queen is located, and featuring several additional satellite nests, apparently queenless. This population structure seems to be very common in this genus and habitat, especially in the bicolor group ( C. savignyi ; Saar et al, , C. drusus; unpublished data). The basis for such population structure could be due to difficulty of dispersal, properties of the substrate, and/or richness of the habitat.…”

“…Genetic (microsatellites) analysis was performed on 348 workers from the Atlit population (12*29 nests) and 72 workers (12*6 nests) from the Habonim population. DNA was extracted with 5% CHELEX (BIO‐RAD) and amplified with eight microsatellite markers that had been designed previously for C. hispanica (Ch23, Ch08, Ch01, Ch10, Ch11 (Darras, et al, )), C. cursor (Cc99, Cc54 (Pearcy, Clémencet, Chameron, Aron, & Doums, ), and C. niger (Cn02 (Saar et al, ) using Type‐it PCR mix (QIAGEN). PCR products were sequenced by ABI3500 sequencer, and genotypes were then visualized with GeneMarker.…”

“…A recently identified new species, C. israelensis, is distributed mainly in the north and north-eastern parts of Israel (Eyer, Seltzer, Reiner-Brodetzki, & Hefetz, 2017;Ionescu & Eyer, 2016), and is the subject of our study. The study was conducted at the distribution edge of this species along the northern coastline of Israel, presenting a similar ecological niche to that of other recently studied congener species (Leniaud et al, 2011;Saar, Leniaud, Aron, & Hefetz, 2014) that display various forms of sociality.…”

Cytonuclear incongruences hamper species delimitation in the socially polymorphic desert ants of theCataglyphis albicansgroup in Israel

“…the coexistence of several queens within colonies). Polygyny in Cataglyphis is rather rare with only three documented cases: C. mauritanica and C. velox in the C. altisquamis group (Eyer et al ., ,b) and C. niger in the C. bicolor group (Leniaud et al ., ; Saar et al ., ). In the C. altisquamis group, nestmate queens are positively related, consistent with parthenogenetic production of new queens (Eyer et al ., ,b).…”

Worker demography and behavior in a supercolonial ant colony: The case of the desert antCataglyphis niger

“…Queens with medium to full oocytes in each ovariole were classified as reproductive queens (Figure S1). DNA was extracted with 5% CHELEX ( BIO‐RAD ) and amplified with 7 microsatellite markers that had been previously designed for C. hispanica (Ch23; Darras, Kuhn, & Aron, ), C. cursor (Cc51, Cc89, and Cc99; Pearcy, Clemencet, Chameron, Aron, & Doums, ), and C. niger (Cn02, Cn04, and Cn08; Saar, Leniaud, Aron, & Hefetz, ) using Type‐it PCR mix (QIAGEN). PCR products were sequenced by ABI3500 genetic analyzer, and genotype analyses were performed with GeneMarker.…”