BEHAVIOURAL AND CHEMICAL STUDIES OF DISCRIMINATION PROCESSES IN THE LEAF-CUTTING laticeps nigrosetosus (FOREL, 1908)

SOUZA, D. J.1, DELLA LUCIA, T. M. C.1, ERRARD, C.2, RICHARD, F-J.2 and LIMA, E. R.1 1Departamento de Biologia , Universidade Federal de Viçosa, CEP 36570-000, Viçosa, MG, Brazil 2Institut de Recherche sur la Biologie de l’Insecte, CNRS UMR 6035, Université de Tours, France Correspondence to: Terezinha Maria Castro Della Lucia, Departamento de Biologia Animal, Universidade Federal de Viçosa, CEP 36570-000, Viçosa, MG, Brazil, e-mail: [email protected] Received May 24, 2004 – Accepted August 11, 2004 – Distributed August 31, 2006 (With 5 figures)

ABSTRACT Leaf-cutting live in symbiosis with a basidiomycete fungus that is exploited as a source of nutrients for ant larvae. Tests of brood transport revealed that Acromyrmex laticeps nigrosetosus workers did not discriminate a concolonial brood from an alien brood. The same result was observed with tests of fungus transport. Adult workers showed no aggressive behaviour to workers from other alien colonies (non-nestmates). There was no qualitative variation in the chemical profiles of larvae, pupae and adult workers from the different colonies. However, quantitative differences were observed between the different colonies. Hypotheses about the lack of intraspecific aggression in this subspecies of ants are discussed. Keywords: leaf-cutting ants, intraspecific aggressiveness, chemical profiles, brood discrimination, fungus discrimination.

RESUMO Estudos químico e comportamental dos processos discriminatórios na formiga cortadeira Acromyrmex laticeps nigrosetosus (Forel, 1908) As formigas cortadeiras vivem em simbiose com um fungo basidiomiceto que é utilizado como fonte de nutriente para suas larvas. Testes de transporte de prole revelaram que as operárias de Acromyrmex laticeps nigrosetosus não discriminaram a prole concolonial de prole estranha. O mesmo resultado foi verificado com testes de transporte do fungo. As operárias adultas não exibiram comportamento agressivo frente a operárias de outras colônias (não companheiras de ninho). Não houve variação qualitativa nos perfis químicos de larvas, pupas e operárias adultas de diferentes colônias. No entanto, diferenças quantitativas foram observadas entre as diferentes colônias. Hipóteses sobre a ausência de agressão intra-específica nesta subespécie de formiga são discutidas. Palavras-chave: formigas cortadeiras, agressividade intraespecífica, perfis químicos, discriminação de prole, discriminação de fungo.

INTRODUCTION & Michener, 1980). Nestmate recognition in ants is defined by the ability of workers to discriminate The ability to recognize kin is widespread, members from allocolonial among conspecifics and especially important in highly social organisms (Stuart & Herbers, 2000). This capacity to recognize (Vander Meer & Morel, 1998). Different methods nestmates and to distinguish them from non- of recognition, based on the origin of the colony nestmates is based on each colony having its own odour (environment and pheromones produced by “chemical signature”, a specific and characteristic each individual or by the queen), are detected in ant chemical cue mixture for each colony (Hölldobler societies (Whitehouse & Jaffé, 1995). It is generally

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accepted that cuticular hydrocarbons (CH) play from the fungus garden, but did not reject eggs an important role in nestmate recognition (Lahav directly obtained from previously isolated queens et al., 1999). The harvester ants Pogonomyrmex (Araújo et al., 1996). In Acromyrmex octospinosus, barbatus can perceive different CH variations and workers are able to recognize their concolonial can use these differences in nestmate recognition brood (Febvay et al., 1984). In Ac. subterraneus (Wagner et al., 2000). In Camponotus fellah, social subterraneus workers can discriminate concolonial isolation induced a divergence of the individual fungus from alien fungus (Viana et al., 2001) and hydrocarbon profiles (Boulay et al., 2000). in this subspecies, a chemical analysis of the brood Intolerance towards isolated C. fellah workers revealed a great similarity between its brood profile starts after about 10-20 days, the time necessary for and on the fungus. the CHs to change and assume individual profiles The objective of this study is to evaluate distinct from the colony profile (Boulay et al., behavioural responses of workers from Acromyrmex 2000). These authors determined that individual laticeps nigrosetosus to concolonial or allocolonial hydrocarbon production is dynamic; workers must larvae, pupae and adults. This research also aims exchange hydrocarbons continually (mainly by to establish the cuticular chemical profiles of trophallaxis) to maintain colonial odour. This is brood and adults of this ant subspecies and their referred to as the Gestalt odour, a mixture of odours implications on behaviour. The worker response to from each individual in the colony and odours from either concolonial or allocolonial fungus was also the environment (Crozier & Dix, 1979). Since tested. individual CH production is dynamic, it is essential for nestmates to homogenize their chemical cues MATERIAL AND METHODS often to create a uniform colony-specific profile (Vander Meer et al., 1989). The uniformity of the chemical profiles results from this constant Collection of ants and rearing conditions homogenization of chemical cues produced by In one leaf-cutting ant survey under all colony members. Ant’s that do not use eucalyptus stands in the region of Paraopeba, trophallaxis, exchange their chemical cues by social Minas Gerais (19° 17’ S and 44° 29’ W; 700 m contacts or allogrooming. Experiments on the non- altitude), Araújo et al. (1997) observed high trophallactic ant Pachycondyla apicalis showed frequencies and densities of Acromyrmex laticeps that physical contacts, as well as allogrooming are nigrosetosus nests throughout the year. These nests able to maintain a uniform colony odour (Soroker were underground, but superficial since they were et al., 1998). On the other hand, Lenoir et al. located at 0.11 m below the soil surface and each (2001) suggested that allogrooming is an important nest generally consisted of a single chamber. behaviour for effective cue transfer in the non- Behavioural and chemical tests were trophallactic ant senilis. conducted with workers from Ac. laticeps Colony brood recognition has also been nigrosetosus colonies. These colonies were demonstrated in several ant species. The concolonial collected at Paraopeba, Minas Gerais state (Brazil) brood is accepted and nourished by workers, while 2 years before starting the experiment. They an allocolonial brood may be rejected (Bonavita- were established in the laboratory and consisted Cougourdan et al., 1989; Bonavita-Cougourdan et of approximately 3,000-4,000 individuals and al., 1993). In fact, the brood possesses chemical numerous broods; the fungus volume was about cues that enable workers to recognize it (Araújo et 2 L. Ants were reared in artificial nests, placed in al., 1996; Viana et al., 2001). 3 L recipients (for more details, see Della Lucia Leaf cutting ants live in symbiosis with a et al., 1993). Humidity, temperature and light-dark basidiomycete fungus that is exploited as a source of (LD) cycles in the rearing room were 75 ± 5%, nutrients for ant larvae. In Atta cephalotes, there is 25 ± 2 °C and 12:12 LD, respectively. Each nest some evidence that a nestmate brood is distinguished had access to a foraging arena (30 cm x 20 cm) (Robinson & Cherrett, 1974). Workers of A. sexdens where leaves and petals from flowers, as well as rubropilosa rejected allocolonial larvae and pupae, water were supplied daily. Behavioural tests were as well as eggs when they were directly removed conducted with workers from four colonies (I, II,

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III, IV) and chemical tests were performed with following aggression index: 0 = non-aggressive workers of three colonies (I, II, III) due to the death interaction (antennal contacts, trophallaxis and al­ of colony IV. logrooming), 1 = threat as indicated by mandibu­ lar opening and curling the abdomen, 2 = biting, Behavioural tests 3 = fight and reciprocal mutilation. The frequencies and duration of each behavioural component were Discrimination of pupae and larvae recorded using computer ODlog software and The methodology used in the bioassays with the overall aggressiveness (AI) shown in each the brood was modified from Araújo et al. (1996). encounter was calculated as follows (Errard & Colonies were deprived of food (leaves) for a 24 h Hefetz, 1997): period prior to the test. This procedure enabled n a faster behavioural response of the workers. !AIi* ti AI = i = 1 (1) Larvae and pupae of four colonies were used. T The brood of each colony was removed from the where A.I.i represents the aggression index, ti the fungus garden and isolated in a Petri dish. Fifteen duration of each act, and T the total interaction minutes later, the minimum time necessary for the time. ants to settle, either larvae or pupae were offered Before each encounter, the marked ant was to workers on a glass slide marked with non-toxic allowed to acclimate by remaining isolated inside ink in order to distinguish a nestmate from a non- a glass tube placed in the center of the Petri dish. nestmate. Positions of the slides were modified Each encounter began by removing the glass tube for each bioassay to avoid conditional behaviour and recording the reaction of the ants towards the of the workers. We conducted 54 replications for marked worker (nestmate or non-nestmate). In the treatments with larvae (The number of replications control encounters, the four ants were nestmates is in parentheses) [I → II (5), I → III (5), I → IV (one marked) and were used to observe that (5), II → I (4), II → III (4), II → IV (4), III → I marking the ant with a colour dot did not affect (5), III → II (5), III → IV (4), IV → I (4), IV →II behaviour of the other ants (visual cues), as well as (4), IV → III (5) and 54 for the control (I → I (13), to establish a baseline behaviour before each test II → II (14), III → III (14), IV → IV (13)]. Fifty and overcome individual variability in the different three replications were conducted with pupae in a tests. The Petri dish was lined with filter paper that 20 min interval. Three types of workers’ behaviour was changed after each test and individuals were occurred: 1. acceptance; the brood was transported tested only once in a given encounter to avoid the to the interior of the nest; 2. rejection; the brood possible effects of familiarization. was transported to the trash pile; 3. indeterminate; We conducted 48 replications for the after 20 min, the workers remained agglomerated treatments ( I → II, I → III, I → IV, II → I, II → around the brood, however they neither transported III, II → IV, III → I, III → II, III → IV, IV → I, it inside the nest, nor transported it to the trash. IV → II, IV → III; we conducted four replications We considered discrimination as the acceptance or for each type of encounter) and 48 for the control rejection of the brood and t-test and χ2 were used (I → I, II → II, III → III, IV → IV; twelve times in for data analysis. each colony). The data were analyzed by Analysis of Variance (ANOVA). Discriminatory ability in adult workers In order to estimate recognition between Fungus discrimination ants, we used aggressiveness tests. The bioassay Concolonial and allocolonial broodless consisted of encounters in a neutral arena (Petri fungus pieces of 100 mg were offered on glass dish 90 mm in diameter) between three workers slides to the colonies on the foraging arena. and one marked with a colour dot on the abdomen These fungus portions were also deprived of that served as the test ant. workers. A total of 32 replicates per colony were For 3 min (until the first physical contact performed as treatment (32 x 4 = 128 tests) and with the marked ant), we recorded the reaction of 32 replicates per colony were performed as control the three ants to the marked ant according to the (32 x 4 = 128 tests). A total of 256 bioassays were

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conducted and results were submitted to the Mann different peaks were recorded, numbered and used Whitney’s U test at 5% of significance. for chemical analysis. For each profile (cuticular The time for initial fungus pick up and for individuals or fungus surnagent), the relative value terminating fungus transport were recorded. For a of each peak with respect to the total was calculated maximum of 70 min, the behaviour of workers was and shown as a percentage. Only peaks with a observed, resulting either in the transport of the relative intensity above 1% were used for analysis. fungus to the nest (= acceptance) or in the transport We then used a hierarchical cluster analysis to the trash piles (= rejection), following Viana (Ward’s method, Euclidean distance, Statistica for et al. (2001). Windows 95 ©) and a discriminant analysis (Sta­ tistica for Windows 95 ©) to estimate the similarity Chemical analysis (or divergence) between the chemical profiles Regarding extraction, each worker (major, of the different parts of each colony. Statistical media and minor), brood (larvae and pupae) from 3 analysis was performed on 54 extracts [18 extracts colonies were killed by freezing. Each ant’s cuticu­ by colony (3 major, 3 media, 3 minor, 3 pupae, lar compounds were extracted by immersion in 3 larvae and 3 fungus) and this was replicated for 2 mL of pentane for 10 min. Larvae and pupae were the 3 colonies] and a total of 31 peaks. immersed for 2 min. to ensure that only cuticular substances were extracted. Fungus extracts (250 mg RESULTS by vial) were obtained using the same methodology, but were immersed in dichloromethane. Behavioural tests Each extract was evaporated and subse­ quently redissolved in 50 µl of pentane of which Discrimination of pupae and larvae 1 µl was injected into an on-column Varian The majority of the brood (55 to 62%) used 3300 GC equipped with a CPSil 5 capillary WCOT in the bioassays was accepted by the receiver Chrompack column (25 m, 0.25 mm Internal colonies, regardless of being nestmates or non- Diameter) that was temperature programmed from nestmates. There was no difference in acceptance 80 °C to 280 °C at 5 °C per minute and then held between nestmate and non-nestmate brood, in at 280 °C for 20 min. Quantification was done by larvae (χ2 = 47.1, p = 0.231) and pupae (χ2 = 40.76, peak integration using an Enica integrator. The p = 0.130) (Figs. 1 and 2).

70 Nestmate Non-nestmate 60

50

40 % 30

20

10

0 Acceptance Undeterminate Rejection Fig. 1 – Behaviour of Acromyrmex laticeps nigrosetosus workers in the presence of concolonial or allocolonial larvae (ex- pressed as acceptance or rejection percentage. There was no statistical difference between the groups (p < 0.05, χ2) for each situation. N = 54 (non-nestmate) and n = 54 (nestmates).

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70 Nestmate Non-nestmate 60

50

40 % 30

20

10

0 Acceptance Undeterminate Rejection Fig. 2 – Behaviour of Acromyrmex laticeps nigrosetosus workers in the presence of concolonial or allocolonial pupae (ex- pressed as acceptance or rejection percentage. There was no statistical difference between the groups (p < 0.05, χ2) for each situation. N = 53 (non-nestmate) and n = 53 (nestmates).

In the assays with larvae, the mean time for or concolonial fungus in this study. However, the a colony to accept a nestmate (7.32 min) was not time of fungus transport to the nest was different statistically different from that for a non-nestmate (p < 0.05, for n = 32 per colony and control tests) (p > 0.05, t-test). These results were similar to depending on the fungus origin. The average those obtained with pupae. It is interesting to point time (minutes) for nestmates to carry their own out that in 40% of the tests, the behaviour of the fungus was 16 ± 12.18 min. (n = 128 ) whereas for workers was undetermined since workers did not allocolonial fungus this time was 36 ± 22.93 min carry their brood to the nest nor did they transport (n = 128). it to trash piles. This means that both nestmates and non-nestmates had difficulties in discriminating the Chemical analysis brood. Chromatogram analysis Discriminatory ability in adult workers Acromyrmex laticeps nigrosetosus workers In all encounters, Ac. laticeps nigrosetosus possess a similar chemical profile that presents no workers from the control treatment did not react qualitative difference as a function of the colony aggressively towards their marked nestmates. source. The most quantifiable compounds (31 peaks) The only behaviour observed among workers was varied quantitatively between the different castes antennal contact. This observed behaviour was not (major, media and minor) (Fig. 3a). In addition, no different when the marked ant was a non-nestmate. qualitative variation appeared between the different AIi between non-nestmates was as low (AIi = 0) as colonies for the pupae (Fig. 3b), larvae (Fig. 3c) that between nestmates. Our data clearly indicated and fungus extracts. that workers of Ac. laticeps nigrosetosus could not discriminate between nestmate and non-nestmate. Hierarchical cluster analysis (HCA) The schematic representation of the clustering Fungus discrimination obtained with the HCA algorithm on the mean Workers of Ac. laticeps nigrosetosus retrieved chemical data of each category (major, media, to the nest both concolonial and allocolonial minor, larvae, pupae and fungus) from each colony fragments of broodless fungus offered at the arena. (1, 2 and 3) shows the nodes separating three There was 100% acceptance of either allocolonial groups (Fig. 4). The first node (26.94) separates (no

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a) Major 65 60 55 50 45 40 35 30 25 20 15 10 5 0 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40

b) Pupae 65 60 55 50 45 40 35 30 25 20 15 10 5 0 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40

c) Larvae 65 60 55 50 45 40 35 30 25 20 15 10 5 0 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40

Fig. 3 — Gas chromatograms of the cuticular profiles of workers (major) and brood (pupae and larvae) of Acromyrmex ­laticeps nigrosetosus subspecies. a) major; b) pupae; and c) larvae.

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30 26.94 26.77

25 20.81

20 16.34 14.87 15

Linkage distance 10

5

0 MJ1 MJ2 MJ3 N1 N2 L2 S3 M3 M1 MM1 MM2 MM3 N3 L3 L1 S2 M2 S1

Fig. 4 — Hierarchical cluster analysis (Ward’s method, Euclidean distances) conducted on the mean of the relative propor- tions (from the 3 colonies) of the 18 major peaks in Acromyrmex laticeps nigrosetosus workers (major: MJ1, MJ2, MJ3), media: MM1, MM2, MM3, minor: M1, M2, M3), A. laticeps nigrosetosus larvae (L1, L2, L3), A. laticeps nigrosetosus pupae (N1, N2, N3) and A. laticeps nigrosetosus fungus (S1, S2, S3). significant difference)major (MJ1, MJ2, MJ3) and DISCUSSION media (MM1, MM2, MM3) individuals from all other extracts (pupae, larvae, minor and fungus), The behavioural and chemical results of this and the second (26.77), which divides pupae (N1, study corroborate the hypothesis that recognition N2, N3) and larvae (L1, L2, L3) from minor (M1, processes are based on the discrimination M2, M3) and fungus (S1, S2, S3) situated at a lower of colonial odour. Our results indicate that but not significant level. This cluster analysis clearly Ac. laticeps nigrosetosus societies are open, reflects the proximity between the same elements because workers show no aggressive behaviour of the different colonies. This detailed statistical towards alien conspecifics. In fact, intraspecific analysis showed that the major and media ants confrontations never exceeded antennal contact clustered together (major/media p = 0.43) forming and non-nestmates interacted peacefully. No distinct groups according to (1) significantly to the allogrooming or trophallaxis between non- brood castes (pupae/larvae p = 0.12; major/pupae nestmates was observed. Chemical profiles of Ac. p < 0.0001; media/pupae p < 0.001; major/larvae laticeps nigrosetosus workers reveal only a slight p < 0.0001; media/larvae p < 0.0001), (2) non divergence among them. The lack of aggressiveness significantly to the worker castemajor/minor ( in this subspecies is related to the lack of a uniform p = 0.25; media/minor p = 0.99) the minor being colony-specific odour as obtained in the chemical very close to the fungus (minor/fungus p = 0.41). analyses. Behavioural tests with freshly collected field colonies revealed no aggression between Discriminant analysis nestmates and non-nestmates (unpublished data). A discriminant analysis was performed on the This may explain the high density of colonies in mean chemical data of each element of the three the study area used by Araújo et al. (1997) and colonies (Fig. 5). Colonies were clustered in 3 not their foraging activity pattern without any hostility significantly distinct groups (100% well clustered, among workers from different colonies in the same

F26,6 = 0.557; P = 0.86). It appeared that chemical foraging area in the field. profiles of each colony element are convergent with Since there was a significant difference be­ those of the other colonies. tween the time to retrieve the concolonial and

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Root 1 vs. Root 2 3.5 3.0 Colony I 2.5 Colony II Colony III 2.0 1.5 1.0 0.5

Root 2 (11%) 0.0 - 0.5 - 1.0 - 1.5 - 2.0 - 2.5 - 5 - 4 - 3 - 2 - 1 0 1 2 3 4 5 Root 1 (88%)

Fig. 5 — Discriminant analysis of chemical compounds (conducted on the mean of the relative proportions of 13 major peaks) for workers (major, media, minor), larvae, pupae and fungus from the different colonies of Acromyrmex laticeps. Distances between groups are not significant: colony I/colony II p = 0.91; colony II/colony III p = 0.47; colony I/colony III p = 0.80. Ellipses are 95% confidence.

allocolonial fungus, it can be said that adult workers aggressiveness may be very high if the defense of Ac. laticeps nigrosetosus are able to discriminate force is small as in this case. allocolonial broodless fungus. However, they did The fact that the colonies used in this not reject alien fungus unlike the results obtained experiment had been fed with the same type of by Viana et al. (2001). Although fungus containing leaves for two years may have influenced their a brood was not tested here, it can be hypothesized discriminatory ability. Different diets influence the that the fungus would also be promptly transported chemical profiles indirectly and consequently the to the nest by non-nestmates because there was no recognition cues in Ac. subterraneus subterraneus brood discrimination by workers of this subspecies. (Richard et al., 2004). In the field Ac. laticeps Future investigations should consider the possibility nigrosetosus workers foraged basically on young of allocolonial fungus acceptance increasing initial Eucalyptus camaldulensis leaves obtained by colony survival. climbing up the trees, cutting and transporting These findings are not compatible with those leaves to the nest (Araújo et al., 1997). According obtained by Araújo et al. (1996) with A. sexdens to these authors, the workers did not show rubropilosa and by Viana et al. (2001) with Ac. trail fidelity while trails were poorly built and subterraneus subterraneus. In both studies, workers vegetation was abundant in the area. The role of were able to detect and reject the allocolonial brood, diets on discrimination between nestmates and although there was a variation in the results with non-nestmate workers of Ac. laticeps nigrosetosus larvae and pupae. Reasons for these differences in the field deserves more investigation. could probably be associated with the small size The strategy of non-discrimination of brood of Ac. laticeps nigrosetosus populations in contrast and allocolonial fungus acceptance by workers of to those of Atta and even to other species of the this subspecies may represent higher probability Acromyrmex. Less aggressive behaviour of success and establishment. Observations of can be considered advantageous to this subspecies behavioural ecology should help in elucidating this since the cost of territorial defense and of greater point.

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Acknowledgments — We are grateful to Mara Garcia Tavares la fourmi Attini Acromyrmex octospinosus (Reich) (Hym. from the Biology Department at Federal University of Formicidae). Act. Coll. Insectes. Soc., 1: 79-86. Viçosa and Ricardo Della Lucia from the Forest Engineering HÖLLDOLBER, B. & MICHENER, C. D., 1980, Mechanisms Department Federal University of Viçosa for their suggestions of identification and discrimination in social . on the manuscript. We also thank Patrizia D’Ettorre and Jean- In: H. Markl (ed.), Evolution of social behaviour: hypothesis Luc Mercier (IRBI, Tours) for providing the ant extracts. This and empirical tests. Chemie Gmbh, Weinheim. work was supported by CAPES-COFECUB, Nº 244-1998- LAHAV, S., SOROKER, V., HEFETZ, A. & VANDER MEER, 2000. R. K., 1999, Direct behavioural evidence for hydrocarbons as ant recognition discriminators. Naturwissenschaften, 86: REFERENCES 246-249. LENOIR, A., CUISSET, D. & HEFETZ, A., 2001, Effects ARAÚJO, M. S., DELLA LUCIA, T. M. C., ARAÚJO, F. S. of social isolation on hydrocarbon pattern and nestmate & BENTO, J. M. S., 1996, Discriminação da prole por recognition in the ant Aphaenogaster senilis (Hymenoptera, operárias companheiras e não companheiras de ninho Formicidae). Insectes Soc., 48: 101-109. em Atta sexdens rubropilosa Forel, 1908 (Hymenoptera, RICHARD, F-J., HEFETZ, A., CHRISTIDES, J-P. & ERRARD, Formicidae). Rev. Bras.Entomol., 40: 101-104. C., 2004, Food influence on colonial recognition and ARAÚJO, M. S., DELLA LUCIA, T. M. C. & MAYHÉ- chemical signature between nestmates in the fungus- NUNES, A. J., 1997, Levantamento de Attini (Hymenoptera, growing ant Acromyrmex subterraneus subterraneus. Formicidae) em povoamento de Eucalyptus na região de Chemoecology, 14: 9-16. Paraopeba, Minas Gerais, Brasil. Rev. Bras. Zoo., 14: 323- ROBINSON, S. W. & CHERRETT, J. M., 1974, Laboratory 328. investigations to evaluate the possible use of pheromones BONAVITA-COUGOURDAN, A., CLEMENT, J-L. & LANGE, of the leaf-cutting ant Atta cephalotes (L.) (Formicidae: C., 1989, The role of cuticular hydrocarbons in recognition Attini) as a component in an attractive bait. Bull. Entomol. of larvae by workers of ant Camponotus vagus: changes in Res., 63: 519-529. the chemical signature in response to social environment SOROKER, V., FRESNEAU, D. & HEFETZ, A., 1998, (Hymenoptera: Formicidae). Sociobiology, 16: 49-74. Formation of colony odor in ponerine ant Pachycondyla apicalis. J. Chem. Ecol., 24: 1077-1090. BONAVITA-COUGOURDAN, A., CLEMENT, J-L. & LANGE, C., 1993, Functional subcaste discrimination (foragers STUART, R. J. & HERBERS, J. M., 2000, Nestmate recognition and brood-tenders) in the ant Camponotus vagus Scop: in ants with complex colonies: within- and between- polymorphism of cuticular hydrocarbon patterns. J. Chem. population variation. Behav. Ecol., 11: 676-685. Ecol., 9: 1461-1477. VANDER MEER, R. K. & MOREL, L., 1998, Nestmate recognition in ants. In: R. K. Vander Meer, M. Breed, M. BOULAY, R., HEFETZ, A., SOROKER, V. & LENOIR, A., Winston & K. E. Espelie (eds.), Pheromone Communication 2000, Camponotus fellah colony integration: worker in Social . Westview Press, Boulder. individuality necessitates frequent hydrocarbon exchanges. Anim. Behav., 59: 1127-1133. VANDER MEER, R. K., SALIWANCHIK, D. & LAVINE, B., 1989, Temporal changes in colony cuticular hydrocarbon CROZIER, R. H. & DIX, M. W., 1979, Analysis of two genetic patterns of Solenopsis invicta: Implications for nestmate models for the innate components of colony odor in social recognition. J. Chem. Ecol., 15: 2115-2125 Hymenoptera. Behav. Ecol. Sociobiol., 4: 217-224. VIANA, A. M. M., FREZARD, A., MALOSSE, C., DELLA DELLA LUCIA, T. M. C., VILELA, E. F. & ANJOS, N., 1993, LUCIA, T. M. C., ERRARD, C. & LENOIR, A., 2001, Criação de formigas cortadeiras em laboratório. In: T. M. Colonial recognition of fungus in the fungus-growing ant C. Della Lucia (ed.), As formigas cortadeiras, Folha de Acromyrmex subterraneus subterraneus (Hymenoptera: Viçosa, Viçosa. Formicidae). Chemoecology, 11: 29-36. ERRARD, C. & HEFETZ, A., 1997, Label familiarity and WAGNER, D., TISSOT, M., CUEVAS, W. & GORDON, D. discriminatory ability of ants reared in mixed groups. M., 2000, Harvester ants utilize cuticular hydrocarbons in Insectes Soc., 44: 189-198. nestmate recognition. J. Chem. Ecol., 26: 2245-2257. FEBVAY, G., MALLET, F. & KERMARREC, A., 1984, WHITEHOUSE, M. E. A. & JAFFÉ, K., 1995, Nestmate Attractivité du couvain et comportement des ouvrières de recognition in the leaf-cutting ant Atta laevigata. Insectes Soc., 42: 157-166. -

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