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Barros, A. T. (2001). Seasonality and relative abundance of Tabanidae (Diptera) captured on horses in the Pantanal, Brazil. Mem Inst Oswaldo Cruz, 96(7), 917–923.
Abstract: Once a month, from June 1992 to May 1993, collections of tabanids on horse were conducted in the Nhecolandia, Pantanal State of Mato Grosso do Sul, Brazil. Tabanid catches using hand nets were conducted from sunrise to sunset at grassland and cerradao (dense savanna) habitats. A total of 3,442 tabanids from 21 species,12 genera, and 3 subfamilies were collected. Although species abundance varied seasonally depending on habitat, no habitat specificity was observed for the most abundant species. In the grassland, 1,625 (47.2%) tabanids belonging to 19 species were collected, while 1,817 (52.8%) tabanids from 17 species were caught in the cerradao. The number of tabanid species varied from 7 during winter (July/August) to 15 in the spring (October). Tabanus importunus (56%) was the most abundant species, followed by T. occidentalis (8.2%), and T. claripennis (8.1%). The tabanid peak, in October, coincided with the beginning of the rainy season. The population peak of most species, including those with higher vector potential, suggests that the rainy season can be considered as the period of potentially higher risk of mechanical transmission of pathogens by tabanids to horses in the region.
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Fenton, B., & Ratcliffe, J. (2004). Animal behaviour: eavesdropping on bats. Nature, 429(6992), 612–613.
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Whiten, A., Goodall, J., McGrew, W. C., Nishida, T., Reynolds, V., Sugiyama, Y., et al. (1999). Cultures in chimpanzees. Nature, 399(6737), 682–685.
Abstract: As an increasing number of field studies of chimpanzees (Pan troglodytes) have achieved long-term status across Africa, differences in the behavioural repertoires described have become apparent that suggest there is significant cultural variation. Here we present a systematic synthesis of this information from the seven most long-term studies, which together have accumulated 151 years of chimpanzee observation. This comprehensive analysis reveals patterns of variation that are far more extensive than have previously been documented for any animal species except humans. We find that 39 different behaviour patterns, including tool usage, grooming and courtship behaviours, are customary or habitual in some communities but are absent in others where ecological explanations have been discounted. Among mammalian and avian species, cultural variation has previously been identified only for single behaviour patterns, such as the local dialects of song-birds. The extensive, multiple variations now documented for chimpanzees are thus without parallel. Moreover, the combined repertoire of these behaviour patterns in each chimpanzee community is itself highly distinctive, a phenomenon characteristic of human cultures but previously unrecognised in non-human species.
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Dugatkin, L. A. (2002). Animal cooperation among unrelated individuals. Naturwissenschaften, 89(12), 533–541.
Abstract: The evolution of cooperation has long been a topic near and dear to the hearts of behavioral and evolutionary ecologists. Cooperative behaviors run the gamut from fairly simple to very complicated and there are a myriad of ways to study cooperation. Here I shall focus on three paths that have been delineated in the study of intraspecific cooperation among unrelated individuals: reciprocity, byproduct mutualism, and group selection. In each case, I attempt to delineate the theory underlying each of these paths and then provide examples from the empirical literature. In addition, I shall briefly touch upon some recent work that has attempted to examine (or re-examine) the role of cognition and phylogeny in the study of cooperative behavior. While empirical and theoretical work has made significant strides in the name of better understanding the evolution and maintenance of cooperative behavior in animals, much work remains for the future. “From the point of view of the moralist, the animal world is on about the same level as the gladiator's show. The creatures are fairly well treated, and set to fight; whereby the strongest, the swiftest and the cunningest live to fight another day. The spectator has no need to turn his thumb down, as no quarter is given em leader the weakest and the stupidest went to the wall, while the toughest and the shrewdest, those who were best fitted to cope with their circumstances, but not the best in any other way, survived. Life was a continuous free fight, and em leader a war of each against all was the normal state of existence.” (Huxley 1888)
Keywords: Animals; Phylogeny; *Social Behavior; Species Specificity
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Reboreda, J. C., Clayton, N. S., & Kacelnik, A. (1996). Species and sex differences in hippocampus size in parasitic and non-parasitic cowbirds. Neuroreport, 7(2), 505–508.
Abstract: To test the hypothesis that selection for spatial abilities which require birds to locate and to return accurately to host nests has produced an enlarged hippocampus in brood parasites, three species of cowbird were compared. In shiny cowbirds, females search for host nests without the assistance of the male; in screaming cowbirds, males and females inspect hosts' nests together; in bay-winged cowbirds, neither sex searches because this species is not a brood parasite. As predicted, the two parasitic species had a relatively larger hippocampus than the non-parasitic species. There were no sex differences in relative hippocampus size in screaming or bay-winged cowbirds, but female shiny cowbirds had a larger hippocampus than the male.
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Gallup, G. G. J. (1985). Do minds exist in species other than our own? Neurosci Biobehav Rev, 9(4), 631–641.
Abstract: An answer to the question of animal awareness depends on evidence, not intuition, anecdote, or debate. This paper examines some of the problems inherent in an analysis of animal awareness, and whether animals might be aware of being aware is offered as a more meaningful distinction. A framework is presented which can be used to make a determination about the extent to which other species have experiences similar to ours based on their ability to make inferences and attributions about mental states in others. The evidence from both humans and animals is consistent with the idea that the capacity to use experience to infer the experience of others is a byproduct of self-awareness.
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Traversa, D., Giangaspero, A., Iorio, R., Otranto, D., Paoletti, B., & Gasser, R. B. (2004). Semi-nested PCR for the specific detection of Habronema microstoma or Habronema muscae DNA in horse faeces. Parasitology, 129(Pt 6), 733–739.
Abstract: Habronema microstoma and Habronema muscae (Spirurida: Habronematidae) are parasitic nematodes which infect the stomach and/or skin of equids. The accurate diagnosis of gastric habronemosis is central to studying its epidemiology, but data on its distribution and prevalence are lacking, mainly due to the limitations of clinical and coprological diagnosis in live horses. To overcome this constraint, a two-step, semi-nested PCR-based assay was validated (utilizing genetic markers in the nuclear ribosomal DNA) for the specific amplification of H. microstoma or H. muscae DNA from the faeces from horses (n = 46) whose gastrointestinal parasite status had been determined at autopsy and whose faeces were examined previously using a conventional parasitological approach. Of these horses examined at autopsy, some harboured adults of either H. microstoma (n= 19) or H. muscae (n =4), and others (n = 7) harboured both species. Most of them were also infected with other parasites, including strongylid nematodes (subfamilies Cyathostominae and Strongylinae), bots and/or cestodes; there was no evidence of metazoan parasites in 2 horses. Larvated spirurid eggs were detected in the faeces of 1 of the 30 horses (3.3 %) shown to be infected with Habronema at autopsy. For this set of 46 samples, the PCR assay achieved a diagnostic specificity of 100 % and a sensitivity of approximately 97 % (being able to specifically detect as little as approximately 0.02 fg of Habronema DNA). The specificity of the assay was also tested using a panel of control DNA samples representing horse, the gastric spirurid Draschia megastoma and 26 other species of parasites from the alimentary tract of the horse. H. microstoma, H. muscae and D. megastoma could be readily differentiated from one another based on the sizes of their specific amplicons in the PCR. The results of this study showed that the performance of the PCR for the diagnosis of gastric habronemosis was similar to that of autopsy but substantially better than the traditional coprological examination procedure used. The ability to specifically diagnose gastric habronemosis in equids should have important implications for investigating the epidemiology and ecology of H. microstoma and H. muscae.
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Giangaspero, A., Traversa, D., & Otranto, D. (2004). [Ecology of Thelazia spp. in cattle and their vectors in Italy]. Parassitologia, 46(1-2), 257–259.
Abstract: The genus Thelazia (Spirurida, Thelaziidae) includes a cosmopolitan group of eyeworm spirurids responsible for ocular infections in domestic and wild animals and transmitted by different species of muscids. Bovine thelaziosis is caused by Thelazia rhodesi Desmarest 1828, Thelazia gulosa Railliet & Henry 1910, and Thelazia skrjabini Erschow 1928, which occur in many countries; T. gulosa and T. skrjabini have been reported mainly in the New World, while T. rhodesi is particularly common in the Old World. In Italy, T. rhodesi was reported in southern regions a long time ago and, recently, T. gulosa and T. skrjabini have been identified in autochthonous cattle first in Apulia and then in Sardinia. Thirteen species of Musca are listed as intermediate hosts of eyeworms, but only Musca autumnalis and Musca larvipara have been demonstrated to act as vectors of Thelazia in the ex-URSS, North America, ex-Czechoslovakia and more recently in Sweden. In Italy, after the reports of T. gulosa and T. skrjabini in southern regions, the intermediate hosts of bovine eyeworms were initially only suspected as the predominant secretophagous Muscidae collected from the periocular region of cattle with thelaziosis were the face flies, M. autumnalis and M. larvipara, followed by Musca osiris, Musca tempestiva and Musca domestica. The well-known constraints in the identification of immature eyeworms to species by fly dissection and also the time-consuming techniques used constitute important obstacles to epidemiological field studies (i.e. vector identification and/or role, prevalence and pattern of infection in flies, etc.). Molecular studies have recently permitted to further investigations into this area. A PCR-RFLP analysis of the ribosomal ITS-1 sequence was developed to differentiate the 3 species of Thelazia (i.e. T. gulosa, T. rhodesi and T. skrjabini) found in Italy, then a molecular epidemiological survey has recently been carried out in field conditions throughout five seasons of fly activity and has identified the role of M. autumnalis, M. larvipara, M. osiris and M. domestica as vectors of T. gulosa and of M. autumnalis and M. larvipara of T. rhodesi. Moreover, M. osiris was described, for the first time, to act as a vector of T. gulosa and M. larvipara of T. gulosa and T. rhodesi. The mean prevalence in the fly population examined was found to be 2.86%. The molecular techniques have opened new perspectives for further research on the ecology and epidemiology not only of Thelazia in cattle but also of other autochthonous species of Thelazia which have been also recorded in Italy, such as Thelazia callipaeda, which is responsible for human and canid ocular infection and Thelazia lacrymalis, the horse eyeworm whose epidemiological molecular studies are in progress.
Keywords: Animals; Cattle/parasitology; Cattle Diseases/epidemiology/*parasitology/transmission; Disease Transmission, Horizontal; Dog Diseases/epidemiology/parasitology/transmission; Dogs/parasitology; Ecosystem; Eye Infections, Parasitic/epidemiology/transmission/*veterinary; Horse Diseases/epidemiology/parasitology/transmission; Horses/parasitology; Humans; Insect Vectors/*parasitology; Italy/epidemiology; Muscidae/*parasitology; Species Specificity; Spirurida Infections/epidemiology/transmission/*veterinary; Thelazioidea/classification/*isolation & purification
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Holekamp, K. E., Sakai, S. T., & Lundrigan, B. L. (2007). Social intelligence in the spotted hyena (Crocuta crocuta). Philos Trans R Soc Lond B Biol Sci, 362(1480), 523–538.
Abstract: If the large brains and great intelligence characteristic of primates were favoured by selection pressures associated with life in complex societies, then cognitive abilities and nervous systems with primate-like attributes should have evolved convergently in non-primate mammals living in large, elaborate societies in which social dexterity enhances individual fitness. The societies of spotted hyenas are remarkably like those of cercopithecine primates with respect to size, structure and patterns of competition and cooperation. These similarities set an ideal stage for comparative analysis of social intelligence and nervous system organization. As in cercopithecine primates, spotted hyenas use multiple sensory modalities to recognize their kin and other conspecifics as individuals, they recognize third-party kin and rank relationships among their clan mates, and they use this knowledge adaptively during social decision making. However, hyenas appear to rely more intensively than primates on social facilitation and simple rules of thumb in social decision making. No evidence to date suggests that hyenas are capable of true imitation. Finally, it appears that the gross anatomy of the brain in spotted hyenas might resemble that in primates with respect to expansion of frontal cortex, presumed to be involved in the mediation of social behaviour.
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Poti, P. (2005). Chimpanzees' constructional praxis (Pan paniscus, P. troglodytes). Primates, 46(2), 103–113.
Abstract: This study investigated chimpanzees' spontaneous spatial constructions with objects and especially their ability to repeat inter-object spatial relations, which is basic to understanding spatial relations at a higher level than perception or recognition. Subjects were six chimpanzees-four chimpanzees and two bonobos-aged 6-21 years, all raised in a human environment from an early age. Only minor species differences, but considerable individual differences were found. The effect of different object samples was assessed through a comparison with a previous study. A common overall chimpanzee pattern was also found. Chimpanzees repeated different types of inter-object spatial relations such as insertion (I), or vertical (V), or next-to (H) relations. However chimpanzees repeated I or V relations with more advanced procedures than when repeating H relations. Moreover, chimpanzees never repeated combined HV relations. Compared with children, chimpanzees showed a specific difficulty in repeating H relations. Repeating H relations is crucial for representing and understanding multiple reciprocal spatial relations between detached elements and for coordinating independent positions in space. Therefore, the chimpanzees' difficulty indicates a fundamental difference in constructive space in comparison to humans. The findings are discussed in relation to issues of spatial cognition and tool use.
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