In animal groups, individual interactions achieve coordinated movements to maintain cohesion. In horse harem groups, herding is a behavior in which males chase females from behind; it is considered to assist with group cohesiveness. However, the mechanisms by which the individuals move to maintain group cohesion are unknown. We applied novel non-invasive methods of drone filming and video tracking to observe horse movements in the field with high temporal and spatial resolution. We tracked all group members and drew trajectories. We analyzed the movements of females and found two phases of interactions based on their timing of movement initiation. The females that moved first were those nearest to the herding male, while the movement initiation of the later females was determined by the distance from the nearest moving female, not by the distance from the herding male. These interactions are unique among animal group movements and might represent a herding mechanism responsible for maintaining group cohesion. This might be due to long-term stable relationships within a harem group and strong social bonds between females. This study showed that the combination of drone filming and video tracking is a useful method for analyzing the movements of animals simultaneously in high resolution.

At the type locality near Miles in Queensland, Australia a queenright colony of Polyrhachis loweryi was found (1 dealate queen, 91 workers, males and brood) within a colony of Rhytidoponera sp. (near aciculata), whereas other colonies of this Rhytidoponera species contained only a few workers of P. loweryi. For experiments and behavioural observations P. loweryi and its hosts were kept in the laboratory for some time. The queenright P. loweryi colony constructed closed nests out of soil and plant fibres, within the host nest, and only containing Polyrhachis specimens. P. loweryi workers in part, remained amid the assembly of Rhytidoponera, from whom they obtained carbohydrate and protein food. In addition, Polyrhachis workers regularly left the host nest. They were able to collect liquid carbohydrate food and to distribute it among conspecific nest mates via trophallaxis. The care of the P. loweryi brood was fully done by P. loweryi itself. However, Rhytidoponera workers were observed carrying P. loweryi brood in addition to their own brood. In artificially induced nest relocations, P. loweryi was able to move to a new nest independently from its host ants, displaying the typical invitation behaviour, trail laying behaviour, and leader independent trail communication found in other members of the genus. Rhytidoponera sp., which in addition to inconspicuous trail marking, performs nest relocation via social carrying, rarely but regularly also carried P. loweryi to the new nest. Whereas Rhytidoponera sp. workers were carried in the typical ponerine posture, P. loweryi workers were carried by them in the formicine posture. We conclude that P. loweryi is best described as a guest ant of Rhytidoponera sp.. The species seems to be less well integrated into the societies of its Rhytidoponera sp. host than the closely related P. lama, a social parasite of Diacamma sp. in Java.In both Polyrhachis species workers from queenright colonies perhaps emigrate with a few eggs or larvae in order to rear them in neighbouring host nests. The adaptive and predispositional reasons for the phyletic development of this parasitic relation remain unclear.

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The formicine ant Polyrhachis lama is a social parasite, exploiting its ponerine host ant species Diacamma sp. In most social parasitic associations, the parasitic species are closely related to their host species group, evolving directly from independent ancestors of the host species. However, in the Polyrhachis lama- Diacamma sp. association, the associated species belong to different ant subfamilies. Based on preliminary field surveys, we had presumed that P. lama might have given up its reproductive division of labour, i.e. workers would be able to produce males as well as workers and females parthenogenetically. In this study, this hypothesis was disproved: Polyrhachis lama workers cannot be fertilized and are only able to produce males. In the host-parasite association originating from nests possessing a P. lama queen, workers penetrate surrounding Diacamma sp. nests, carrying brood for rearing within these satellite nests. In this peculiar way, a single P. lama colony is able to exploit several Diacamma sp. colonies simultaneously.

ObjectivesFrom the first description by Leo Kanner [1], autism has been an enigmatic neurobehavioral phenomenon. The new genetic/genomic technologies of the past decade have not been as productive as originally anticipated in unveiling the mysteries of autism. The specific etiology of the majority of cases of autism spectrum disorder (ASD) is unknown, although numerous genetic/genomic variants and alterations of diverse cellular functions have been reported. Prompted by this failure, we have investigated whether the metabolomics approach might yield results which could simultaneously lead to a blood-based screening/diagnostic test and to treatment options. Methods Plasma samples from a clinically well-defined cohort of 100 male individuals, ages 2-16+ years, with ASD and 32 age-matched typically developing (TD) controls were subjected to global metabolomic analysis. ResultsWe have identified more than 25 plasma metabolites among the approximately 650 metabolites analyzed, representing over 70 biochemical pathways, that can discriminate children with ASD as young as 2 years from children that are developing typically. The discriminating power was greatest in the 2-10 year age group and weaker in older age groups. The initial findings were validated in a second cohort of 83 children, males and females, ages 2-10 years, with ASD and 76 age and gender-matched TD children. The discriminant metabolites were associated with several key biochemical pathways suggestive of potential contributions of increased oxidative stress, mitochondrial dysfunction, inflammation and immune dysregulation in ASD. Further, targeted quantitative analysis of a subset of discriminating metabolites using tandem mass spectrometry provided a reliable laboratory method to detect children with ASD. Conclusion Metabolic profiling appears to be a robust technique to identify children with ASD ages 2-10 years and provides insights into the altered metabolic pathways in ASD, which could lead to treatment strategies. ObjectivesTo uncover novel traits associated with nicotine and alcohol use genetics, we performed a phenome-wide association study in a large multi-ethnic cohort. Methods We investigated 7,688 African-Americans (AFR), 1,133 Asian-Americans (ASN), 14,081 European-Americans (EUR), and 3,492 Hispanic-Americans (HISP) from the Women's Health Initiative, analyzing risk alleles located in the CHRNA5-CHRNA3 locus (rs8034191, rs1051730, rs12914385, rs2036527, and rs16969968) for nicotine-related traits and ADH1B (rs1229984 and rs2066702) and ALDH2 (rs671) for alcohol-related traits with respect to anthropometric characteristics, dietary habits, social status, psychological circumstances, reproductive history, health conditions, and nicotine-and alcohol-related traits. ResultsThe investigated loci resulted associated with novel traits: rs1229984 were associated with family income (p=4.1*10 −12 ), having a pet (p=6.5*10 −11 ), partner education (p=1.8*10 −10 ), "usually expect the best" (p=2.4*10 −7), "felt calm and peaceful" (p=2.6*10 ), and num...