Colony dehydration and water collection by specialized caste in the leaf-cutting ant Atta sexdens rubropilosa

Social organization enables leaf-cutting ants to keep appropriate micro-ecological nest conditions for the fungus garden (their main food), eggs, larvae and adults. To maintain stability while facing changing conditions, individual ants must perceive destabilising factors and produce a proper behavioral response. We investigated behavioral responses to experimental dehydration in leaf-cutting ants to verify if task specialization exists, and to quantify the ability of ant sub-colonies for water management. Our setup consisted of fourteen sub-colonies, ten of which were randomly assigned to different levels of experimental dehydration with silica gel, whereas the remaining four were controls. The ten experimental sub-colonies were split into two groups, so that five of them had access to water. Diverse ant morphs searched for water in dehydrated colonies, but mainly a caste of small ants collected water after sources had been discovered. Size specialization for water collection was replicable in shorter experiments with three additional colonies. Ants of dehydrated colonies accumulated leaf-fragments on the nest entrance, and covering the fungus garden. Behaviors that may enhance humidity within the nests were common to all dehydration treatments. Water availability increased the life span of dehydrated colonies.

Caste, land and livestock holdings in India: an analysis

A ban on grazing, particularly by small ruminants, forms an important component of the Forest Policy and Joint Forest Management arrangements in India. Some caste groups keep larger number of small ruminants than the others. It is considered as a social trait that is sought to be corrected through extension efforts. This paper analyses the livestock structure of households by using a model of household behaviour based on profit maximisation. It shows that landholding plays a crucial role in livestock structure of households and because certain caste groups have smaller landholding they tend to keep small ruminants that can feed on the common lands and forest areas. The policy of a ban or restriction on grazing adversely affects such caste groups who therefore come to resent it.

Re-mapping class and caste consciousness: short narratives of South Asian diaspora in Australia

Thanks to Bollywood, a Non-Resident Indian (NRI) is predominantly imagined, back home in India, as super-rich, fully westernized in manners and doing India proud in foreign lands. One reason for this as explained by renowned Bollywood producer-director Late Yash Chopra, in his address at the first Pravasi Bharatiya Divas (Expatriate Indians Day) in 2003, is that as a director he is also working as a ‘historian’ and carrying on his shoulders the ‘moral responsibility [ … ] to depict India [and the Indian Diaspora] at its best’. In this regard, Ghassan Hage also notes that the ‘last thing’ the migrants (particularly men) would like to share with their families back home is shocking stories about racism, discrimination or prejudices that they may have experienced in public or the workplace. Such a revelation would obviously be followed by ‘why did you make us suffer and move to the end of the world just to get demeaned and insulted?’ Hage further notes that therefore the migrants’ familial and class experiences, be it in films, literature or even some sociological studies, are often ‘portrayed as a positive experience’ and this is ‘how the whole migratory enterprise continues to legitimise itself’'. It could be argued that this is one of the reasons the alleged ‘racist’ attacks against Indian students received so much attention in the Indian media. It was not just discrimination but the notion of discrimination and second class treatment (based on skin colour and origin) against the revered and much envied diasporic Indian that created such a media furor in India.

Status, caste, and market in a changing Indian village

When social and economic conditions change dramatically, status hierarchies in place for hundreds of years can crumble as marketization destabilizes once rigid boundaries. This study examines such changes in symbolic power through an ethnographic study of a village in North India. Marketization and accompanying privatization do not create an independent sphere where only money matters, but due to a mix of new socioeconomic motives, they produce new social obligations, contests, and solidarities. These findings call into question the emphasis in consumer research on top-down class emulation as an essential characteristic of status hierarchies. This study offers insights into sharing as a means of enacting and reshaping symbolic power within a status hierarchy. A new order based on markets and consumption is disrupting the old order based on caste. As the old moral order dissolves, so do the old status hierarchies, obligations, dispositions, and norms of sharing that held the village together for centuries. In the microcosm of these gains and losses, we may see something of the broader social and economic changes taking place throughout India and other industrializing countries.

Biometrics studies of caste development in Nasutitermes coxipoensis (Isoptera; Termitidae)

A biometric study of caste development was carried out using Nasutitermes sp., by measuring the height, width, and length of the head, the length and width of the pronotum and mesonotum, and the length of the posterior tibia. These measurements were taken on 200 individuals, including larvae, nymphs, workers, pre-soldiers and soldiers. For instar separation, it was verified that the Principal Component Analysis (P.C.A.) was the most efficient methodology. Results of this analysis showed that Nasutitermes coxipoensis follows the general pattern of development presented by other Nasutitermes.

Morphological caste differences in the neotropical swarm-founding polistine wasp, Brachygastra lecheguana (Hymenoptera : Vespidae, Polistinae, Epiponini)

Morphological caste differences and ovary conditions were analyzed in colony of Brachygastra lecheguana. The results indicate the presence of individuals with ovary development but uninseminated (intermediates). In addition, these females were similar in morphology to workers, suggesting that, in this case, intermediates are ovary-developed workers. Queens were morphologically larger than workers and intermediates in some characters and smaller in others. Multivariate analysis showed that queens were highly distinct. These results indicate that castes are pre-imaginally determined in B. lecheguana.

Overview of Caste Differentiation in the Polistinae, Emphasizing the Neotropical Swarm-Founding Polistinae (Hymenoptera, Vespidae, Epiponini)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Caste Asymmetries in the Neotropical Swarm-Founding Wasp Polybia (Trychothorax) ignobilis (Hymenoptera, Vespidae, Epiponini)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

MORPHOLOGICAL CASTE DIFFERENCES IN POLYBIA AEQUATORIALIS (HYMENOPTERA: VESPIDAE: POLISTINAE: EPIPONINI), A SOCIAL WASP of THE HIGHLANDS of COSTA RICA

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caste in the swarming wasps: 'queenless' societies in highly social insects

Morphometric data for 30 species of swarming wasps (Vespidae: Polistinae: Epiponini) are presented, representing all currently recognized genera. Data are coded according to whether females that were shown by dissection to be egglayers are larger, similar, or smaller for each dimension than non-egglayers. These data are analysed in a phylogenetic framework with primitively social Polistes and Mischocyttarus as outgroups. Representative measurements are illustrated to show that most genera of Epiponini appear to have ancestry in a lineage that has no queen caste comparable with either the primitively social outgroups, or the more derived species of the tribe. This analysis indicates that a conspiracy of workers that operates without a queen characterizes the societies of many Epiponini, or their recent ancestors. (c) 2008 The Linnean Society of London.

Caste Differences in Polybia emaciata, a Mud-Nesting Eusocial Wasp (Hymenoptera: Vespidae), that Bear on Pre-Imaginal Determination but not Size Differences

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caste differences in Pseudopolybia compressa (Hymenoptera: Vespidae: Polistinae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)