Development of Gaze Following Abilities in Wolves (Canis Lupus)

The ability to coordinate with others' head and eye orientation to look in the same direction is considered a key step towards an understanding of others mental states like attention and intention. Here, we investigated the ontogeny and habituation patterns of gaze following into distant space and behind barriers in nine hand-raised wolves. We found that these wolves could use conspecific as well as human gaze cues even in the barrier task, which is thought to be more cognitively advanced than gazing into distant space. Moreover, while gaze following into distant space was already present at the age of 14 weeks and subjects did not habituate to repeated cues, gazing around a barrier developed considerably later and animals quickly habituated, supporting the hypothesis that different cognitive mechanisms may underlie the two gaze following modalities. More importantly, this study demonstrated that following another individuals' gaze around a barrier is not restricted to primates and corvids but is also present in canines, with remarkable between-group similarities in the ontogeny of this behaviour. This sheds new light on the evolutionary origins of and selective pressures on gaze following abilities as well as on the sensitivity of domestic dogs towards human communicative cues

Gaze following in an asocial reptile (Eublepharis macularius)

Gaze following is the ability to utilise information from another's gaze. It is most often seen in a social context or as a reflexive response to interesting external stimuli. Social species can potentially reveal utilisable knowledge about another's future intentions by attending to the target of their gaze. However, in even more fundamental situations, being sensitive to another's gaze can also be useful such as when it can facilitate greater foraging efficiency or lead to earlier predator detection. While gaze sensitivity has been shown to be prevalent in a number of social species, little is currently known about the potential for gaze following in asocial species. The current study investigated whether an asocial reptile, the leopard gecko (Eublepharis macularius), could reliably use the visual indicators of attention to follow the gaze of a conspecific around a barrier. We operated three trial conditions and found subjects (N = 6) responded significantly more to the conspecific demonstrator looking up at a laser stimulus projected onto an occluder during the experimental condition compared to either of two control conditions. The study's findings point toward growing evidence for gaze-following ability in reptiles, who are typically categorised as asocial. Furthermore, our findings support developing comparative social cognition research showing the origins of gaze following and other cognitive behaviours that may be more widely distributed across taxonomic groups than hitherto thought

Rodent damage to rice crops is not affected by the water‑saving technique, alternate wetting and drying

Rice farmers in Southeast Asia are hesitant to adopt the water-saving technology, alternate wetting and drying (AWD), for fear the practice will lead to increased rodent pest activity, consequently exacerbating yield loss. We examined the effects of AWD on the population dynamics, habitat use and damage levels inflicted on rice crops by the most important rodent pest of rice in Indonesia and the Philippines, Rattus argentiventer and R. tanezumi, respectively. Rice crop damage levels were not affected by the water management scheme employed. Rodent activity in rice fields was not influenced by water level. Both species tended to use the rice paddies over bunds regardless of water level, indicating that something other than water affects their habitat use, and we argue it is likely that the perceived risk of predation is the primary factor driving habitat use. Activity levels and damage inflicted by rodent pests on rice were not correlated. AWD had no effect on breeding and population dynamics of these species. Breeding of R. argentiventer is tied to the growth stages of rice, while available resource dictates breeding by R. tanezumi. Our findings clearly indicate that rice farmers in both Indonesia and the Philippines have no cause to reject AWD based on concerns that AWD would exacerbate crop losses by rodents. Given AWD is being promoted as a climate-smart technology for rice production in Asia and Africa, we strongly recommend its adoption without concerns that it would aggravate rodent pest impacts in lowland irrigated rice cropping systems

The importance of the altricial – precocial spectrum for social complexity in mammals and birds:A review

Various types of long-term stable relationships that individuals uphold, including cooperation and competition between group members, define social complexity in vertebrates. Numerous life history, physiological and cognitive traits have been shown to affect, or to be affected by, such social relationships. As such, differences in developmental modes, i.e. the ‘altricial-precocial’ spectrum, may play an important role in understanding the interspecific variation in occurrence of social interactions, but to what extent this is the case is unclear because the role of the developmental mode has not been studied directly in across-species studies of sociality. In other words, although there are studies on the effects of developmental mode on brain size, on the effects of brain size on cognition, and on the effects of cognition on social complexity, there are no studies directly investigating the link between developmental mode and social complexity. This is surprising because developmental differences play a significant role in the evolution of, for example, brain size, which is in turn considered an essential building block with respect to social complexity. Here, we compiled an overview of studies on various aspects of the complexity of social systems in altricial and precocial mammals and birds. Although systematic studies are scarce and do not allow for a quantitative comparison, we show that several forms of social relationships and cognitive abilities occur in species along the entire developmental spectrum. Based on the existing evidence it seems that differences in developmental modes play a minor role in whether or not individuals or species are able to meet the cognitive capabilities and requirements for maintaining complex social relationships. Given the scarcity of comparative studies and potential subtle differences, however, we suggest that future studies should consider developmental differences to determine whether our finding is general or whether some of the vast variation in social complexity across species can be explained by developmental mode. This would allow a more detailed assessment of the relative importance of developmental mode in the evolution of vertebrate social systems

Influência de variáveis socioeconômicas, clínicas e demográfica na experiência de cárie dentária em pré-escolares de Piracicaba, SP Influence of socioeconomic, clinical and demographic variables on caries experience of preschool children in Piracicaba, SP

OBJETIVO: Avaliar a influência de variáveis socioeconômicas, clínicas e demográfica na experiência de cárie em pré-escolares de 5 anos de idade da cidade de Piracicaba. METODOLOGIA: A amostra consistiu de 728 crianças matriculadas em 22 pré-escolas públicas (n = 428) e 18 pré-escolas privadas (n = 300). A cárie dentária foi avaliada pelos índices ceo-d e ceo-s e pela detecção de lesão inicial (LI). Outras variáveis clínicas como gengivite, apinhamento, espaçamento, fluorose e respiração bucal também foram coletadas. As variáveis socioeconômicas (renda familiar mensal, número de residentes na mesma casa, escolaridade do pai e da mãe, habitação e posse de automóvel) foram obtidas por meio de um questionário semi-estruturado enviado aos pais. RESULTADOS: As médias (desvio-padrão) do ceo-d e ceo-s foram de 1,30 (2,47) e 3,08 (7,55), respectivamente, sendo que 62,2% da amostra estava livre de cárie. As médias (desvio-padrão) do ceo-d+LI e ceo-s+LI foram 1,72 (3,36) e 3,45 (7,94), respectivamente e 59,7% estavam livres de cáries. Por meio da análise de regressão logística múltipla, as crianças com fluorose (Odds Ratio-OR=0,40) ou de famílias com renda superior a 4 salários mínimos (OR = 0,49) apresentaram menor probabilidade de ter experiência de cárie. Aquelas com gengivite (OR = 1,87) tiveram maior chance de ter a doença. Para o critério de diagnóstico de cárie com a inclusão de LI, as crianças com fluorose (OR = 0,39) ou de famílias com renda superior a 4 salários mínimos (OR = 0,52) tiveram menor chance de ter cárie. Aquelas com gengivite (OR=1,80), apinhamento (OR = 2,63 e OR = 1,01) ou respiração bucal (OR = 1,37) apresentaram maior probabilidade de ter a doença. CONCLUSÃO: Os pré-escolares que apresentaram gengivite, apinhamento, respiração bucal ou renda familiar mensal inferior a 4 salários mínimos tiveram maior probabilidade de ter experiência de cárie. Assim, o planejamento de ações de prevenção e intervenção direcionadas a este público seria essencial para o controle da doença.<br>AIM: To evaluate the influence of socioeconomic, clinical and demographic variables on caries experience in 5-year-old preschool children from Piracicaba. METHODS: The sample consisted of 728 children attending 22 public (n=428) and 18 private (n=300) preschools. Dental caries were measured using the dmft/dmfs indexes and by detecting initial caries lesion (IL). Gingivitis, crowding, spacing, fluorosis, and mouth breathing were also recorded. Socioeconomic variables (monthly family income, number of people living in the household, parents' schooling, home ownership, and car ownership) were collected by means of a parental semi structured questionnaire. RESULTS: The mean (standard deviation) values for dmft and dmfs indexes were 1.30 (2.47) and 3.08 (7.55) respectively; and 62.2% of the children were caries-free. The mean (standard deviation) values for dmft+LI and dmfs+LI were 1.72 (3.36) and 3.45 (7.94), respectively and 59.7% were caries-free. By means of multiple logistic regression analyses, children with fluorosis (OR=0.40) or family income > 4 minimum wages (OR=0.49) were less likely to experience caries. Those with gingivitis (OR=1.87) were more prone to have the disease. Considering the diagnostic threshold including IL, the multiple logistic regression analyses showed that children with fluorosis (OR=0.39) or family income > 4 minimum wages (OR=0.52) were less likely to have caries. Those with gingivitis (OR=1.80), crowding (OR=2.63 e OR=1.01) or mouth breathing (OR=1.37) were more likely to have the disease. CONCLUSION: The preschool children who presented gingivitis, crowding, mouth breathing or monthly family income < 4 minimum wages were more likely to experience caries. In this way, planning preventive and operative actions targeted at these children would be essential for caries control