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The following dissertation presents the history of myrmecology from the times of Ulisse Aldrovandi up to the works of Edward O. Wilson in the 20th century. The oldest mentions of ants in the Antiquity and the Middle Ages are also partially elaborated upon. A special emphasis is given to the general idea about ants as developed by each of the authors, as well as to the mapping out of the contemporary ideas about social insect. This work points out that the portrait of the ant has always been related to the contemporary conception of human society and humanity as such. Throughout its history, myrmecology has always been strongly influenced by anthropomorphism, as the picture of the ant would be derived from the social order, political system and the general opinion on what constitutes human nature. On the other hand, though, myrmecology has also helped to shape the picture of humanity, because the conclusions drawn from myrmecological studies were applied to humans. Therefore, entomology started to influence anthropology and vice versa. In the Antiquity, ants were viewed basically as farmers; only harvester ants were known, they were seen as working on a field, going to the marketplace or holding celebratory festivals. The medieval picture of the ant drew heavily on the Antiquity ideas, but it added...

Les attines sont des fourmis champignonnistes dans la zone allant des Etats-Unis à l'Argentine en passant par la Caraïbe. Les dégâts causés par ces ravageurs sont considérables et estimés à plusieurs millions de dollars par an. Elles sont de ce fait considérées comme l'un des premiers fléaux de l'agriculture de la zone (Cameron & Riggs, 1985 ; Fowler et al., 1986). En Guadeloupe, la "fourmi manioc" (Acromyrmexoctospinosus Reich) cause de nombreux dommages, aussi bien pour l'agriculture que dans les milieux naturels. Les dégâts occasionnés par ces fourmis ont nécessité l'utilisation de pesticides de synthèse. pour tenter de les combattre. La dangerosité de ces substances pour les milieux naturels et anthropisés ainsi que pour la santé publique est un contexte favorable à l'exploration de nouvelles pistes telles que l'utilisation de plantes à usages phytosanitaires. L'objet principal de cette thèse consiste à savoir si on peut déceler à partir de l'ethnopharmacologieTRAMIL des usages permettant de combattre cette fourmi et son symbiote fongique, Leucocoprinuss 'gongylophorus (Heim) MoeIler. Les protocoles retenus et présentés dans ce travail permettent d'observer les effets des usages de plantes choisis sur la survie et le comportement des insects et sur la croissance du symbiote. Ils ont été sélectionnés pour leur potentialité à mettre en évidence les différents types d'effets des extraits végétaux (insecticide par contact, insectifuge, toxique par ingestion, fongistatique ou fongicide). Six usages traditionnels issus de cinq plantes sont testés sur la fourmi: Mammea americana L., Nerium oleander L., Nicotiana tabacum L., Rollinia mucosa (Jacq.) Baill. et Trichilia pallida Sw. Cinq autres usages traditionnels sont testés sur le champignon : Allium cepa L., Allium sativum L., Lycopersicom esculentum Mill., Manihot esculenta Crantz et Senna alata (L.) Roxb. Les resultants obtenus permettent de dégager quelques pistes de lutte intéressantes contre ce ravageur. / Leaf-cutting ants are fungus-growing ants.Their geographie distribution ranges from southern United States to northern Argentina, incIuding the West Indies, Economic losses due to these ants were estimated at several million dollars per year. The latter statement makes they are considered as one of the most important pest species of the agricultural productions (Cameron & Riggs, 1985 ; Fowler et al., 1986). In (Guadeloupe, the most important invasive pest species which caused important losses in forests, gardens and field crops is 'cassava ant' (Acromyrmex octospinosus Reich). These huge losses required to use, synthetic chemical pesticides to control these leaf-cutting ants, the consequence of which is, irreversible' injuries on environment and on human health. As a matter of fact, this situation has prompted an increasing interest in alternative methods for pest control like plants with pesticide used. The main objective of this thesis is to know if traditional ethnopharmacological TRAMIL uses could help to fight against this ant and against the symbiotic fungus, Leucocoprinus gongylophorus (Heim) . Moeller. Methods used and presented in this work aIIowed to observe effects of selected plant uses on mortality and insect's behavior. The protocols performed were selected for their potentiality to detect the different types of insecticidal effects (contact toxicity, repellent effect, toxicity by ingestion, fungicidal or fungistatic). Six traditional plant uses of five plants were tested on the ant : Mammea americana L., Nerium oleander L., Nicotiana tabacum L.,Rollinia mucosa (Jacq) Baill. and Trichilia pallida Sw.Five other plants uses were tested on the fungus:Allium cepa L.,Lycopersicon esculentum Mill.,Manihot esculenta Crantz and Senna alata (L.) Roxb.The obtained résults provide us with some interesting trails to fight against this pest.

abstract: Ant colonies provide numerous opportunities to study communication systems that maintain the cohesion of eusocial groups. In many ant species, workers have retained their ovaries and the ability to produce male offspring; however, they generally refrain from producing their own sons when a fertile queen is present in the colony. Although mechanisms that facilitate the communication of the presence of a fertile queen to all members of the colony have been highly studied, those studies have often overlooked the added challenge faced by polydomous species, which divide their nests across as many as one hundred satellite nests resulting in workers potentially having infrequent contact with the queen. In these polydomous contexts, regulatory phenotypes must extend beyond the immediate spatial influence of the queen. This work investigates mechanisms that can extend the spatial reach of fertility signaling and reproductive regulation in three polydomous ant species. In Novomessor cockerelli, the presence of larvae but not eggs is shown to inhibit worker reproduction. Then, in Camponotus floridanus, 3-methylheptacosane found on the queen cuticle and queen-laid eggs is verified as a releaser pheromone sufficient to disrupt normally occurring aggressive behavior toward foreign workers. Finally, the volatile and cuticular hydrocarbon pheromones present on the cuticle of Oecophylla smaragdina queens are shown to release strong attraction response by workers; when coupled with previous work, this result suggests that these chemicals may underly both the formation of a worker retinue around the queen as well as egg-located mechanisms of reproductive regulation in distant satellite nests. Whereas most previous studies have focused on the short-range role of hydrocarbons on the cuticle of the queen, these studies demonstrate that eusocial insects may employ longer range regulatory mechanisms. Both queen volatiles and distributed brood can extend the range of queen fertility signaling, and the use of larvae for fertility signaling suggest that feeding itself may be a non-chemical mechanism for reproductive regulation. Although trail laying in mass-recruiting ants is often used as an example of complex communication, reproductive regulation in ants may be a similarly complex example of insect communication, especially in the case of large, polydomous ant colonies. / Dissertation/Thesis / Doctoral Dissertation Biology 2020

abstract: Social animals benefit from the aggregation of knowledge and cognitive processing power. Part of this benefit comes from individual heterogeneity, which provides the basis to group-level strategies, such as division of labor and collective intelligence. In turn, the outcomes of collective choices, as well as the needs of the society at large, influence the behavior of individuals within it. My dissertation research addresses how the feedback between individual and group-level behavior affects individuals and promotes collective change. I study this question in the context of seed selection in the seed harvester ant, Pogonomyrmex californicus. I use both field and laboratory studies to explore questions relating to individual behavior: how forager decision-making is affected through information available in the nest and at the seed pile; how workers interact with seeds in the nest; and how forager preferences diverge from each other’s and the colony’s preference. I also explore the integration between individual and colony behavior, specifically: how interactions between the foraging and processing tasks affect colony collection behavior; how individual behavior changes affect colony preference changes and whether colony preference changes can be considered learning behavior. To answer these questions, I provided colonies with binary choices between seeds of unequal or similar quality, and measured individual, task group, and colony-level behavior. I found that colonies are capable of learning to discriminate between seeds, and learned information lasts at least one month without seed interaction outside of the nest. I also found that colony learning was coordinated by foragers receiving updated information from seeds in the nest to better discriminate and make choices between seed quality during searches for seeds outside of the nest. My results show that seed processing is essential for stimulating collection of novel seeds, and that foraging and processing are conducted by behaviorally and spatially overlapping but distinct groups of workers. Finally, I found that foragers’ preferences are diverse yet flexible, even when colonies are consistent in their preference at the population level. These combined experiments generate a more detailed and complete understanding of the mechanisms behind the flexibility of collective colony choices, how colonies incorporate new information, and how workers individually and collectively make foraging decisions for the colony in a decentralized manner. / Dissertation/Thesis / Doctoral Dissertation Biology 2020

Mutualistic interactions between species are balanced on a delicate scale of net benefits to both interacting partners. The dynamics of such interactions could change depending on the context in which these interactions occur. One of the most well-studied models for interspecies mutualisms are myrmecophytic systems, also known as ant-plant systems, where the host plant (myrmecophyte) provides shelter (domatia), solely or along with food resources, for ant partners, while the domatia-resident ants intensively patrol and protect the host plant from herbivory. In some cases, nutrient flux has also been reported from the ant-derived debris in the domatia to the host plant. Such mutualisms are often vulnerable to exploitation by non-mutualist organisms or interlopers such as non-protective ants and other invertebrates that use the plant rewards without any returns. Since provision of domatia and food imposes costs on the host plants, the trajectory of evolution in such cases where protection is partial or absent needs investigation to understand the evolution of myrmecophytism. In this thesis, we investigate the possibility of evolution of myrmecophytism in the absence of universal protection by partner ants, using the unique semi-myrmecophyte (domatia are not expressed in all individuals of the species) Humboldtia brunonis as the study model. H. brunonis is endemic to the tropical wet evergreen forests of the Western Ghats of India. Being locally abundant in its distribution range, this plant species has also been used in characterising forest types in the Western Ghats. H. brunonis provides domatia (modified stem internodes) and food for ants in the form of extrafloral nectar (EFN) on leaves and bracts of floral buds in all individuals. Each domatium has a self-opening slit, which could have led to the domatia being accessed and inhabited by numerous ants and other non-ant invertebrates throughout its distribution range. Of these, only one ant species, Technomyrmex albipes, has been reported to be significantly protective against herbivores, and the protection received by the plant is reported to be restricted only to one site where T. albipes is most abundant. In the light of the above, the possible explanation for continued expression of rewards (domatia as well as EFN) in the absence of universal protection was investigated. Chapter 1: Introduction This chapter starts with a brief history of the concept of mutualism, evolution and maintenance of mutualism, and trophic mutualism amongst organisms in general. This is followed by a description of ant–plant mutualisms, and the various interactions that drive the interaction in such systems, with a more detailed emphasis on trophic mutualism in ant-plants, and stable isotope analysis as a technique that is used to study trophic mutualism in ant-plants. The study system, Humboldtia brunonis is introduced, and all the studies on this system preceding this current thesis are discussed in the light of findings in other ant-plant systems. Lastly, the objectives of the thesis are briefly introduced as separate chapters. Chapter 2: Context dependency of rewards and services in an Indian ant–plant interaction: southern sites favour the mutualism between plants and ants (published in Journal of Tropical Ecology) Earlier studies on the H. brunonis system have shown that there is geographic variation in the occupancy of the domatia, with domatia in the northern part of the H. brunonis range being dominantly occupied by an arboreal earthworm species, while domatia in the south are mostly occupied by ants, especially the sole protective ant T. albipes. Further, it has been reported that herbivory is significantly reduced in the presence of ants in the south. In the present study, conducted at 5 sites spanning the distribution range of H. brunonis, we observed that there is a geographic variation in various ant-related plant traits such as abundance of domatia-bearing individuals, number of nectaries per leaf, size of nectaries, and volume and composition of the EFN, with a clear north–south increasing gradient. However, strong protection mutualism was observed only at one site in the south where herbivory pressure was highest. By comparing our results with earlier findings, we show that in addition to geographic variation, there is also temporal variation in the strength of protection mutualism, and that protection mutualism in this system is context-dependent. These results provide new perspectives on the evolution of myrmecophytism. Chapter 3: Leaf expansion and foliar extrafloral nectar as defence strategies in a paleotropical ant-plant Humboldtia brunonis (Fabaceae) (a section of this chapter is submitted to Biotropica) Despite the absence of universal protection against herbivory, H. brunonis plants constitutively secrete EFN and domatia. We therefore explored other non-chemical defences in this system, and investigated possible explanations for the continued reward production. We observed rapid rate of leaf expansion during the early and most vulnerable phase of leaf phenology, and propose this as a strategy to escape herbivory. The young leaves are also subject to being infested by phloem-feeding Hemiptera, but there was seldom any case of ants tending Hemiptera for honeydew (sugary material excreted by the Hemiptera) on the plant. We analysed the sugar and amino acids compositions of EFN, honeydew and phloem sap, and found that EFN composition was much richer and more attractive (to ants) than honeydew, thereby suggesting that EFN could possibly function to distract ants from tending Hemiptera on the plant, thereby avoiding further damage to the plant. We also observed that EFN composition was much richer than phloem sap, and thereby confirmed that EFN is not mere phloem exudate; rather, our results suggests that EFN could possibly be synthesized actively in the secretory cells of the extrafloral nectary. Anatomical observations of the foliar nectaries further support the synthesis of EFN in the secretory cells of the nectary. Chapter 4: Nutritional benefits from domatia-inhabitants in an ant–plant interaction: interlopers do pay the rent (published in Functional Ecology) In this chapter, we explore how a myrmecophytic system could evolve in the absence of protection benefits from the partner ants. We investigate non-protective benefits, specifically trophic (nutrient) benefits, from the protective and non-protective ants and other invertebrates to the host plant, using stable isotope techniques. We selected three representative inhabitant species for our analysis, viz., the protective ant T. albipes, a non-protective ant Crematogaster dorhni, and the arboreal earthworm Perionyx pullus. We observed that earthworms contributed approximately 9% while protective or non-protective ants contributed approximately 17% of the nitrogen to the plant tissues nearest to the domatium. We also observed from 15N labelling experiments that that nutrients from the domatia are not restricted solely to the domatia-bearing branch but could travel to distant non-domatia bearing branches as well. This study demonstrated for the first time that non-protective ants and non-ant invertebrates that inhabit the domatia, and hitherto referred to as interlopers, could be in a trophic mutualism with the host plant, thereby proposing the possibility of trophic mutualism as a factor for the evolution and maintenance of the domatia trait in addition to or in the absence of protection mutualism. It is also possible that fitness benefits of bearing domatia, acquired via trophic mutualism, could later facilitate the establishment of a specialised ant–plant protection mutualism. Chapter 5: Structure and development of the caulinary domatia of Humboldtia brunonis In this chapter, we investigate the morphology of domatia at different ontogenetic stages in order to understand the mode of development of the domatia. Our observations show that the domatium of H. brunonis is formed spontaneously near the terminal end of a growing branch, next to the young apical shoot. It appears as a young swollen internode which is soft and fleshy with the pith tissue still present. As the domatia grows and expands, the collective effect of both schizogeny as well as lysogeny, act on on the pith region. We also observed acropetal lignification of the pith cells around the hollow chamber. We investigate micro-scale anatomy of the inner wall of the domatia using scanning electron microscopy, and observed that the inner lining of the domatia cavity have canaliculated, lignified sclerenchyma with numerous plasmodesmata (intercellular pits) that could facilitate the flow of occupant-derived nutrients supporting trophic interaction between the plant and its domatia inhabitants. We also observed fungal mycelia-like structures in ant-occupied domatia that suggests the possibility of a fungus as a third party in the ant–plant trophic mutualism, as is observed in some other myrmecophytic systems. This aspect however needs further investigation. Chapter 6: Conclusion In this chapter, the main findings of the preceding chapters are summarised. A general conclusion of the thesis is provided, and future directions leading from the present thesis are also listed. The present thesis has explored the dynamics of interactions between a unique semi-myrmecophyte and its domatia-inhabitants; while the unprotected host plant resorts to an escape strategy to evade foliar herbivory, the ants (and other invertebrates) seem to have bid “a farewell to arms” and yet maintain a mutualism with its host via nutrient exchange. The results of this thesis contribute to furthering our current understanding of the evolution and stability of inter-species mutualisms.

The work presents life and work of Vladimir Jan Amos Novak, it shows his main thoughts unified by the principle of sociogenesis and points at its inspiration in older traditions of german and russian biology. It also concerns his anthropology as related to the principle of sociogenesis and shows some peculiar Novak's contributions, mainly his opinions on progessive neotenization of man and evolutionary tedency for association. It grasps the principle of sociogenesis as a biological and also a political concept and therefore shows its very political consequences presented mainly on his social thoughts. The work also deals with the relations between eastern and western science on Novák's efforts to unify all sciences under one universal evolutionary framework regardless its geographical belonging. Throughout the work is Novak shown in the context of man-animal relations and the principle of sociogenesis as arising from myrmecological studies. There are therefore presented anthropological works of three important myrmecologists A. Forel, W.M. Wheeler and E.O. Wilson as inspired in the study of ants.

<p dir="ltr">Given the relatively poor visual acuity of compound eyes, many insects have developed alternative means for navigating their environment. For example, insects often rely on chemosensation to find food, mates, and inter- and intraspecific communication. Eusocial insects in particular have developed complex systems of pheromone communication to organize their colonies, enabling them to partition labor for foraging, brood care, and colony defense tasks to different portions of the colony. A variety of genes coding for proteins are involved in detecting these chemicals, including gustatory receptors, ionotropic receptors, and odorant receptors (ORs). Eusocial insects, and especially ants, have evolved an expanded clade of ORs in their genome, likely due to an increased reliance on pheromones compared to other insects. The ability to recognize nestmates from non-nestmates is one of the vital functions performed by these ORs, which detect hydrocarbons present on the cuticle to distinguish friend from foe. However, research into the details of nestmate recognition has been stymied due to difficulties in manipulating OR genes. Despite advances in genetic sequencing and manipulation technologies, strict reproductive divisions within most ant lineages make generating transgenic ants nearly impossible, and so we have been left with limited options to further investigate these receptors. To narrow down the ORs that could be involved in nestmate recognition in the Argentine ant (Mayr, 1868), I took a multi-pronged approach of generating tissue transcriptomes to identify ORs that are selectively upregulated in the antennae, as well as conducting a phylostratigraphic analysis to identify which OR genes arose more recently in the Argentine ant genome. While conducting these analyses, it became necessary to reannotate the set of Argentine ant OR genes, due to current published annotations not containing the full breadth of <i>L. humile</i> ORs. Finally, I orally administered fluorescently-labelled dsRNA to workers, and tracked the extent to which ingested dsRNA is capable of traversing the tissues of ant workers, to investigate whether RNAi is a viable method for investigating gene function for genes showing tissue-selective expression. I discovered a subset of OR genes that are highly expressed in the antennae and confirmed that dsRNA is able to reach the antennae and knock down OR gene expression through ingestion, meaning that RNA interference is a viable method for the practical study of ant OR genes and can be used to further explore how individual ORs regulate nestmate recognition.</p>