Rimozione di sedimenti per fluitazione dal serbatoio di Sernio (SO)

Il presente lavoro descrive la rimozione di un ingente quantitativo di sedimenti (circa 100'000 tonnellate) dal serbatoio di Sernio, in provincia di Sondrio, effettuata tra maggio e luglio del 2009. Il sedimento \ue8 stato evacuato per fluitazione (flushing), nel sostanziale rispetto dei vincoli preventivamente stabiliti sulla concentrazione di solidi sospesi (CSS) delle acque scaricate. Tali limitazioni hanno lo scopo di contenere l\u2019impatto delle operazioni sugli ecosistemi acquatici coinvolti. La CSS \ue8 stata controllata regolando il livello nel serbatoio, la portata in uscita e, in un secondo tempo, mediante l\u2019utilizzo di escavatori meccanici. La gestione delle operazioni si \ue8 basata sul costante monitoraggio della CSS poco a valle dell\u2019area di intervento. La campagna di misura \ue8 stata ulteriormente estesa a valle, per un tratto di circa 40 km lungo l\u2019asta dell\u2019Adda, al fine di quantificare la riduzione della CSS per effetto combinato di diluizione e deposizione

What is it like to be a jealous dog?

Jealousy is a good candidate for comparative studies due to its clear adaptive value in protecting social bonds and affective relationships. Dogs are suitable subjects for investigating the evolution of jealousy, thanks to their rather sophisticated socio-cognitive abilities — which in some cases parallel those reported for human infants — and thanks to their long-lasting relationship with humans. The work of Cook and colleagues (2018) addresses the issue of jealousy in dogs through the lens of neuroscience, examining the relationship between the amygdala and jealousy. Their experiment has a number of methodological flaws that prevent distinguishing jealousy from other internal states; it also lacks behavioral indicators that could help in this endeavor. Nevertheless, it is an admirable step towards a multidisciplinary approach to the investigation of non-basic emotions in nonhuman species

What is it like to be a jealous dog? Commentary on Cook et al. on Dog Jealousy

Abstract: Jealousy is a good candidate for comparative studies due to its clear adaptive value in protecting social bonds and affective relationships. Dogs are suitable subjects for investigating the evolution of jealousy, thanks to their rather sophisticated socio-cognitive abilities \u2014 which in some cases parallel those reported for human infants \u2014 and thanks to their long-lasting relationship with humans. The work of Cook and colleagues (2018) addresses the issue of jealousy in dogs through the lens of neuroscience, examining the relationship between the amygdala and jealousy. Their experiment has a number of methodological flaws that prevent distinguishing jealousy from other internal states; it also lacks behavioral indicators that could help in this endeavor. Nevertheless, it is an admirable step towards a multidisciplinary approach to the investigation of non-basic emotions in nonhuman species

Red-green color vision in three catarrhine primates

The evolution of the red-green visual subsystem in trichromatic primates has been linked to foraging advantages, specifically the detection of either ripe fruits or young leaves amid mature foliage, and to the intraspecific socio-sexual communication, namely the signal of the male rank, the mate choice and the reproductive strategies in females. New data should be added to the debate regarding the evolution of trichromatic color vision. Three catarrhine primates were observed to achieve this goal. The research was performed on captive groups of vervet monkeys (Chlorocebus aethiops), pig-tailed macaques (Macaca nemestrina) and chimpanzees (Pan troglodytes) housed at Parco Natura Viva - Garda Zoological Park (Italy). Using pairs of red-green bags containing the same hidden reward in comparable outdoor enclosures, we recorded the choices by observed individuals (n = 25) to investigate the role of color cues in choosing an object. The results indicate that chimpanzees used red color as cue to choose an object that contains food by showing a preference toward red objects; in contrast, vervet monkeys and pig-tailed macaques do not demonstrate a clear choice based on the color of the object. Our findings highlight the importance of the foraging hypothesis but not rule out the potential role of the intraspecific socio-sexual communication and may serve to add useful information to the debate regarding the adaptive value of the evolution of color vision in order to fill a phylogenetic gap from Old World monkeys to humans. Future studies should address the role of socio-sexual communication, such as the selection of the reproductive partner of both high genetic quality and with compatible genes, to determine how this influenced the evolution of color vision in non-human primates

When the owner does not know: comparing puppies and adult dogs' showing behavior

Domestic dogs have been shown to engage in interspecific communication with their owners using a flexible repertoire of signals (i.e., gaze, vocalizations, and postures). This ability is influenced by ontogenetic development as well as breed selection. Different aspects of this phenomenon have been studied using the out of reach/hidden object task in which a piece of food is shown to the dog and then hidden in an unreachable spot by the experimenter. Dogs' behavioral displays toward the target and the owner (ignorant about the location of the food) have been observed. The complex communicative behavior dogs exhibit in this context is defined as showing behavior and includes attention-getting components directed toward the owner, and directional components directed toward the target. No study has investigated the ontogenetic development of this behavior. In the current study, we compared the showing behavior in 4-6 month old puppies and 2-11 year old adults in an out of reach task involving the hiding of a food reward in one of two cabinets. Dogs were exposed to three conditions: (1) Owner with Food (OF), (2) Owner No Food (ONF), and (3) Alone with food (AF). Dogs showed more gaze alternations when both the food and the owner were present confirming the intentional and referential nature of this behavior. Contrary to our expectations, we found no differences between the showing behaviors of 4-6 month old puppies and adult dogs. This study provides interesting preliminary evidence of showing behavior in puppies. Further studies are needed to gain a deeper understanding of the factors influencing this communicative behavior (i.e., breed, level of training). Furthermore, longitudinal studies should be performed from the age of 2 months up to 1 and 2 years to better clarify the influence of development and experience on showing behavior in domestic dogs

Wolf-like or dog-like? A comparison of gazing behaviour across three dog breeds tested in their familiar environments

Human-directed gazing, a keystone in dog\u2013human communication, has been suggested to derive from both domestication and breed selection. The influence of genetic similarity to wolves and selective pressures on human-directed gazing is still under debate. Here, we used the \u2018unsolvable task\u2019 to compare Czechoslovakian Wolfdogs (CWDs, a close-to-wolf breed), German Shepherd Dogs (GSDs) and Labrador Retrievers (LRs). In the \u2018solvable task\u2019, all dogs learned to obtain the reward; however, differently from GSDs and LRs, CWDs rarely gazed at humans. In the \u2018unsolvable task\u2019, CWDs gazed significantly less towards humans compared to LRs but not to GSDs. Although all dogs were similarly motivated to explore the apparatus, CWDs and GSDs spent a larger amount of time in manipulating it compared to LRs. A clear difference emerged in gazing at the experimenter versus owner. CWDs gazed preferentially towards the experimenter (the unfamiliar subject manipulating the food), GSDs towards their owners and LRs gazed at humans independently from their level of familiarity. In conclusion, it emerges that the artificial selection operated on CWDs produced a breed more similar to ancient breeds (more wolf-like due to a less-intense artificial selection) and not very human-oriented. The next step is to clarify GSDs\u2019 behaviour and better understand the genetic role of this breed in shaping CWDs\u2019 heterospecific behaviour

Timing and presence of an attachment person affect sensitivity of aggression tests in shelter dogs

Different test series have been developed and used to measure behaviour in shelter dogs in order to reveal individuals not suitable for re-homing due to their aggressive tendencies. However, behavioural tests previously validated on pet dogs seem to have relatively low predictability in the case of shelter dogs. Here, we investigate the potential effects of (1) timing of the behaviour testing and (2) presence of a human companion on dogs' aggressive behaviour. In Study I, shelter dogs (n=25) showed more aggression when tested in a short test series two weeks after they had been placed in the shelter compared to their responses in the same test performed 1–2 days after arrival. In Study II, the occurrence of aggressive behaviour was more probable in pet dogs (n=50) in the presence than in the absence of their passive owner. We conclude that the sensitivity of aggression tests for shelter dogs can be increased by running the test in the presence of a caretaker, and after some period of acclimatisation to the new environment. This methodology could also provide better chances for successful adoption

Pet dogs' behavior when the owner and an unfamiliar person attend to a faux rival

While dog owners ascribe different emotions to their pets, including jealousy, research on secondary emotions in nonhuman animals is very limited and, so far, only one study has investigated jealousy in dogs (Canis familiaris). This work explores jealousy in dogs one step further. We conducted two studies adapting a procedure devised to assess jealousy in human infants. In each study 36 adult dogs were exposed to a situation in which their owner and a stranger ignored them while directing positive attention towards three different objects: a book, a puppet and a fake dog (Study 1: furry; Study 2: plastic). Overall, the results of both studies do not provide evidence that the behavioral responses of our dogs were triggered by jealousy: we did not find a clear indication that the fake dogs were perceived as real social rivals, neither the furry nor the plastic one. Indeed, dogs exhibited a higher interest (i.e. look at, interact with) towards the fake dogs, but differences in the behavior towards the fake dog and the puppet only emerged in Study 2. In addition, many of the behaviors (protest, stress, attention seeking, aggression) that are considered distinctive features of jealousy were not expressed or were expressed to a limited extent, revealing that dogs did not actively try to regain their owner's attention or interfere with the interaction between the owner and the faux rival. Finally, a differentiated response towards the attachment figure (the owner) and the unfamiliar person (the stranger) did not emerge. Differently from what reported in human infants, dogs' behavior towards the attachment figure and the stranger interacting with the potential competitor (in this case, the fake dog) did not significantly differ: in both studies dogs paid attention to the owner and the stranger manipulating the fake dog to the same extent. In conclusion, we do not exclude that dogs could possess a rudimentary form of jealousy, but we suggest that research on this topic should require the use of a real social interloper (conspecific or human) and more naturalistic procedures

Why do dogs (Canis familiaris) select the empty container in an observational learning task?

Many argue that dogs show unique susceptibility to human communicative signals that make them suitable for being engaged in complex co-operation with humans. It has also been revealed that socially provided information is particularly effective in influencing the behaviour of dogs even when the human’s action demonstration conveys inefficient or mistaken solution of task. It is unclear, however, how the communicative nature of the demonstration context and the presence of the human demonstrator affect the dogs’ object-choice behaviour in observational learning situations. In order to unfold the effects of these factors, 76 adult pet dogs could observe a communicative or a non-communicative demonstration in which the human retrieved a tennis ball from under an opaque container while manipulating another distant and obviously empty (transparent) one. Subjects were then allowed to choose either in the presence of the demonstrator or after she left the room. Results showed a significant main effect of the demonstration context (presence or absence of the human’s communicative signals), and we also found some evidence for the response-modifying effect of the presence of the human demonstrator during the dogs’ choice. That is, dogs predominantly chose the baited container, but if the demonstration context was communicative and the human was present during the dogs’ choice, subjects’ tendency to select the baited container has been reduced. In agreement with the studies showing sensitivity to human’s communicative signals in dogs, these findings point to a special form of social influence in observational learning situations when it comes to learning about causally opaque and less efficient (compared to what comes natural to the dog) action demonstrations