Ethology

Unto Others (UO) is an important book for all with a genuine interest in evolutionary biology, and right on target for everyone interested in human behavior. It is also of great relevance for those interested in the effects of the global human population increase, and the interaction of population and environment, aspects which will be emphasized in this review. UO is a truly interdisciplinary exploration of the paradox of explaining the existence of both the egoistic (i.e., selfish) and the altruistic (unselfish) behaviors and motives. UO draws upon data and arguments from biology, philosophy, psychology, and anthropology.

Dionisios Youlatos (2011) Substrate use and locomotor modes of the Neotropical pygmy squirrel Sciurillus pusillus (E. Geoffroy, 1803) in French Guyana. Zoological Studies 50(6): 745-750. The Neotropical pygmy squirrel Sciurillus pusillus is the smallest South American squirrel. This primitive sciurid is rarely encountered and exhibits morphological and behavioral specializations related to bark gleaning and bark and/or exudate feeding. The present account reports the 1st quantitative data on substrate use and locomotor patterns of S. pusillus from a high terra-firme forest in French Guyana. S. pusillus made extensive use of medium vertical supports. The most frequent locomotor modes were claw-climbing and reversion, an orthograde airborne switching mode. Quadrupedalism was used to a lesser extent. The behavioral repertoire of S. pusillus was examined in light of its postcranial morphological features. Together, they suggest a large degree of vertical trunk foraging for bark and/or exudates similar to what was reported for other pygmy squirrels in Africa and Asia. More-detailed studies are required to elucidate these patterns of morphological convergence in pygmy squirrels across tropical forests worldwide.

Callitrichids have been proposed as communal breeders, with non-reproductive animals acting as helpers. Reports in the literature attest to the high variability in the behaviour of helpers. The present study assessed four proximate factors involved in helping in captive Cullitbrix~uccbuJ: age, gender and experience of helpers and composition of their groups. Forty-eight helpers from 15 families from Natal (Brazil) and Reading (UK) colonies were observed during the first 4 weeks of life of new-born twins. Infant carrying, transfers and retrieval, and duration of carrying bouts were registered. Results showed that the presence of helpers decreased the costs of infant carrying, with a negatively significant correlation between group size and mean percentage of carrying. Age, but not gender, was a significant factor for infant carrying, transfers and retrieval, and mean duration of carrying bouts, with older helpers contributing more than younger ones. Singletons and oldest non-reproductive offspring carried infants more, and longer, than twins and offspring with older siblings present in the group. Experience decreased motivation and actual carrying time, but not to a significant level. Age, experience and group composition appeared important factors in the display of infant care by helpers in captive CuLlitbtixjaccbus.

The effect of sensory input on hormones is essential to any explanation of mammalian behavior, including aspects of physical attraction. The chemical signals we send have direct and developmental effects on hormone levels in other people. Since we don t know either if, or how, visual cues might have direct and developmental effects on hormone levels in other people, the biological basis for the development of visually perceived human physical attraction is currently somewhat questionable. In contrast, the biological basis for the development of physical attraction based on chemical signals is well detailed.

Gunnison|s prairie dogs "Cynomys`unnisoni# emit multiple!note alarm calls to terrestrial predators that vary in acoustic structure according to the eliciting stimulus[ The characteristics of the predator that are salient with respect to alarm call variation\ however\ are poorly understood[ Although the behavior of predators has been shown to in~uence alarm call production in other species of ground! dwelling sciurids\ the degree to which sciurid alarm calls describe physical characteristics of predators has not been addressed independently of the e}ects of variation in predator behavior[ The e}ect of variation in the size and shape of the eliciting stimulus was studied by presenting silhouette models to a colony of prairie dogs and recording the alarm calls that were elicited[ Discriminant function analysis on 6 variables measured from spectrograms revealed that the alarm calls di}ered with respect to silhouette[ These results suggest that information with respect to stimulus size and shape is encoded in prairie dog alarm calls[

Locomotor activity in a field population of the freshwater crab, Potamon fluviatile, was studied during the breeding season by means of radio-telemetry and by direct counts of active animals along a transect of the stream. The basic pattern of crabs' locomotor activity can be described as a sequence of short distance movements around the shelters (foraging movements), followed by rarer long distance displacements (wandering movements). Whilst direct counting showed that the crabs exhibit a broadly nocturnal rhythm in foraging movements, no daily periodicity in wandering activity was revealed by telemetry. There is sexual difference in these latter excursions: females move farther along the stream and into the surrounding terrestrial habitat than do males. This behaviour is in contrast to observations made during the non-breeding season and is probably related to the stage of female reproduction.

Nautilus is a remnant of an externally shelled cephalopod lineage that flourished between 450 and 60 million years ago. It is a deep-water scavenger that lacks the complex brain and behavioural repertoire of its soft-bodied relatives, the coleoid cephalopods. Nautilus makes repeated, nightly migrations from deep to shallow water along coral reef slopes to forage, thus an ability to navigate to known locations may be selectively advantageous. Alternatively, drifting passively with the current may be sufficient to locate food and mates distributed randomly over a large area. The derived neural structures that support learning and memory in coleoids are absent from the nautilus brain, indicating that substantial differences between learning abilities in nautilus and coleoids are likely. However, our previous work has demonstrated both associative and spatial learning in nautilus. In laboratory experiments, we tested whether Nautilus pompilius could learn to navigate towards a goal location using either visual cues or motor responses. Results indicate that animals relied both on proximate and distant visual cues to orient but did not use egocentric cues, a somewhat surprising finding given that nautilus spends most of its time in near darkness. Animals learned visual information rapidly and in some cases were able to switch to other tactics when salient visual cues were removed or manipulated.

Homing in the box turtle, Terrapene carolina, has been well documented, but the mechanisms involved are largely unknown. We used laboratory and field experiments to determine if the geomagnetic field may be used as an orientational cue. Turtles were trained in the laboratory to move along an east/west axis and were tested for directionality in a circular arena. Control turtles with dummy weights attached to the carapace oriented significantly to the training direction. Experimental turtles with magnets attached to the carapace were randomly oriented. In field tests, turtles were displaced from their home ranges to 4 release sites located symmetrically about the home site. Controls were displaced under normal magnetic field strength (Helmholtz coils off) and experimentals were displaced under increased field strength (15% increase over local geomagnetic field strength). The initial orientation of the control turtles clustered significantly in the homeward direction while the initial orientation of experimental turtles was not clustered in the homeward direction. Both control and experimental turtles showed compass orientation clustered in an eastward direction regardless of the directional relationship between the release site and home. This compass orientation appears to mask, to some degree, the homeward orientation of the turtles.

Sleeping site selection by the golden!handed tamarin Saguinus midas midas] The role of predation risk\ proximity to feeding sites\ and territorial defence[ Ethology 094\ 0924*0940[ Abstract Tamarin monkeys\ of the genus Saguinus\ spend over half their lives at arboreal sleeping sites[ The decision as to which site to use is likely to have considerable _tness consequences[ These decisions about sleeping sites by three troops of golden! handed tamarin Saguinus midas midas were examined over a 8!mo period at a rainforest site in French Guiana[ Data are presented on the physical nature of sleeping sites\ their number\ position within home ranges\ and pattern of use and reuse\ aspects of behaviour at retirement and egress\ and predation attempts on the study troops[ Cumulative plot analysis indicated that a tamarin troop used 29Ð 39 sleeping sites in a 099!day period\ approximately half of which were used very infrequently\ so that consecutive reuse was never greater than three nights[ Sleeping trees were superior in architectural parameters and liana weight to non!sleeping trees[ There were no more sleeping sites than expected within the home range boundary region of the tamarins or in areas of overlap with the home ranges of neighbouring troops[ Tamarins selected sleeping sites nearest to the last feeding site of the day on 14) of occasions[ The study troops engaged in a number of activities that may reduce predation risk^raptor attacks on the study troops over 8 mo were frequent but unsuccessful[ Tamarins often visited a sleeping site several hours before arrival\ and were more likely to visit a site before use if they had not used it recently[ The decision to select a sleeping site therefore involved knowledge of the previous frequency of use of that site[ Corresponding author] Richard Day\ Lyewood House\ Peters_eld Road\ Ropley\ Hampshire SO13 9ET\ UK[ E!mail] legolasÝithilien[net

Cooperation poses theoretical problems because the behaviors of individuals can benefit others. Evolutionary and game-theory explanations that focus on maximizing one's own material outcomes are usually supported by experimental models with isolated and anonymous subjects. Cooperation in the natural world, however, is often a social act whereby familiar individuals coordinate behaviors for shared outcomes. Social cooperation is also associated with a cooperation bias expressed as a preference for cooperation even when noncooperation is immediately more beneficial. The authors report on evidence for such a bias in a captive group of bottlenose dolphins that voluntarily preferred to receive petting from human guides by using a pairwise coordinated approach, even though this was more difficult, and total petting amount was thereby reduced. To explain why this bias occurs, the authors propose an integrated behavioral-evolutionary approach whereby performance is determined by two kinds of immediate outcomes: material gains and intrinsic affective states associated with cooperating. The latter can provide reinforcement when immediate material gains are reduced, delayed, or absent. Over a lifetime, this proximate mechanism can lead to cooperative relationships whose long-term ultimate consequences can be adaptive.

Factors which contribute to the fact that an individual maintains a relationship of quality with its environment, and thus is well adjusted to it, are the same factors which favor its social dominance. In a context in which resources are limited or can become scarce, dominance orders get established because it is to the interest of individuals to compete, and because there exist individual differences in competitive ability due to various degrees of individual adaptation. Individuals which are less adapted learn to avoid futile confrontations with opponents which they assess as superior in adaptation to themselves in the light of acquired eco-socio-cognitive experiences. Social organization of a given species is a compromise between living alone and not being able to profit from the important advantages of living in a group, and living in group of which the major disadvantage is to have to compete with others. The biological value of social organization as a complex property emergin...

Predators often have nonconsumptive effects (NCEs) on prey. For example, upon detection of predator cues, prey can reduce feeding activities to hamper being detected by predators. Previous research showed that waterborne chemical cues from green crabs (Carcinus maenas, predator) limit the dogwhelk (Nucella lapillus, prey) consumption of barnacles regardless of dogwhelk density, even though individual predation risk for dogwhelks decreases with conspecific density. Such NCEs might disappear with dogwhelk density if dogwhelks feed on mussels, as mussel stands constitute better antipredator refuges than barnacle stands. Through a laboratory experiment, we effectively found that crab chemical cues limit the per-capita consumption of mussels by dogwhelks at low dogwhelk density but not at high density. The combination of tactile and chemical cues from crabs, however, limited the dogwhelk consumption of mussels at both dogwhelk densities. The occurrence of such NCEs at both dogwhelk densities could have resulted from tactile cues indicating a stronger predation risk than chemical cues alone. Overall, the present study reinforces the notions that prey evaluate conspecific density when assessing predation risk and that predator cue type affects their perception of risk.

The mbuna cichlids of Lake Malawi are a diverse, monophyletic, and recently derived clade. Sexual selection is thought to have accelerated their rapid diversification, though the mechanism by which this has occurred remains unknown. In this study, we examine the effect that male-male interactions have on female preference. We first used a short interaction experiment as a proxy for male dominance. We then measured female preference for (1) a single, isolated male; (2) a group of three, highly ranked males, relative to a group of lower ranked males; and (3) a group of three, mixed-ranked males against a similar group of mixed-rank males. We found that male dominance was highly correlated with male standard length. Female preference for male standard length and for dominance rank was significant in both isolated and group interactions. However, females only showed preference for groups of interacting males when males were segregated by dominance rank, not when groups were composed of both dominant and subordinate males. The results suggest that male-male contests influence female mating decisions. By investigating the rules that dictate the outcomes of such interactions we can elucidate the role that behavior plays in the diversification of this species-rich lineage.

An animal's response to predatory attack may depend upon which part of its body is the focus of that attack, because of differential vulnerability to injury. Many avian and mammalian predators direct attacks preferentially toward the prey's head, so simulated attacks that do not have this focus may elicit nonnatural responses. We ÔpeckedÕ 152 free-ranging adult male garter snakes (Thamnophis sirtalis parietalis) in Manitoba either on the head or the midbody, and recorded their responses. The snakesÕ antipredator tactics were affected not only by body size (larger snakes performed threat displays more often) and body temperature (hotter snakes were more likely to flee), but also by location of the attack. Pecks to the head generally resulted in snakes coiling and hiding their heads, often simultaneously elevating and wriggling their tails in an apparent distraction display. In contrast, pecks to the midbody stimulated either escape responses, or (in snakes that did not flee) open-mouthed threat displays. More generally, antipredator tactics may respond in flexible ways to details of the predator-prey encounter (including attributes of the habitat as well as the morphology and behavior of both participants) and hence, experimental studies need to carefully simulate such details. The part of the body under attack may be an important factor in this respect.

The relationship between dogs and their owners is characterized by an affective and enduring bond. It has been suggested that oxytocin might be the underlying mechanism driving this relationship, however evidence is mixed. In this study we tested whether intranasally administered oxytocin (compared to saline) would influence dogs' behavioural synchrony and shared attention towards their owners. Each individuals' pre and post administration oxytocin concentrations (measured in urine) were included in the analyses. Urinary oxytocin concentrations after administrations were positively associated with dogs' duration of social proximity and looking behaviours towards their owners supporting the role of oxytocin in modulating dogs' human-directed social behaviours.

Como carnívoro oportunista, el Gran falso murciélago vampiro espectral (Vampyrumspectrum) se encuentra en la parte alta de la pirámide alimenticia al igual que otros grandes carnívoros de los bosques tropicales. La especie se distribuye desde Veracruz, México hasta el centro de Brasil y Norte de Bolivia. En Ecuador y Perú ha sido registrada a ambos lados de la cordillera de los Andes, en altitudes desde el nivel del mar hasta los 1550 msnm. Se reporta aquí un estudio de un refugio de V. spectrum, con cuatro individuos, encontrado en una cavidad del tronco de un árbol de Ceibo (Ceiba pentrandra), en el bosque Matorral seco de tierras bajas de la Reserva Ecológica Arenillas (REA) del cantón Arenillas, provincia de El Oro, suroccidente de Ecuador. El estudio se llevó a cabo entre julio 2011 y julio 2012, donde se colectó una vez por mes los restos de presas y excretas depositados en una red permanente instalada en la base del refugio.
Adicionalmente, se colocó una cámara trampa para registrar la actividad de cacería durante cinco días. El material identificado revela que la colonia de Vampyrum spectrum se alimentó de: 15 especies diferentes de aves, con un rango de tamaño preferido desde 12,5 hasta 21,5 cm, siendo la especie más consumida Cyanocorax mystacalis, además de cinco especies de mamíferos y cuatro de insectos de tamaño considerable. No se realizaron capturas de los murciélagos para no ahuyentarlos, por lo que se desconoce datos de sexo, según su apariencia se presume que se trata de una pareja adulta y sus crías desarrolladas.
Los resultados preliminares del comportamiento, indican un patrón de cacería solitaria, realizada por un adulto del grupo, a quien se registró ingresar al refugio con presas decapitadas; según las muestras analizadas, fue evidente que las vísceras no fueron consumidas.

Evolutionary theory proposes that adaptive traits are reproduced more successfully than maladaptive traits. Accordingly, natural selection should favor heterosexuality as it facilitates reproduction and the propagation of genes. However, the question becomes, what has maintained homosexuality in a small but consistent percentage of the human population? Research into the evolutionary and hormonal factors associated with a homosexual orientation have yielded provocative but inconsistent results. It also suggests that human sexual orientation, and in particular homosexual orientation, is too complex to be described by one simple model or a single research discipline. The current paper treads a new path and emphasizes an integrative approach for the understanding of homosexuality. The authors examine the combined effects of evolutionary factors and neurohormonal processes on the development of a homosexual orientation. It is suggested that research into the topic could benefi t from an examination of and change in some of the assumptions upon which much past research has been based.

As yet, cooperative breeding has been described only for some fish species. However, evidence is accumulating that it is widespread among Lake Tanganyika cichlids. We studied the cooperative breeding system of the substrate breeding cichlid Neolamprologus savoryi. Breeding groups typically consisted of a large breeding male with one to four breeding females and three to 33 helpers (mean group size: 14.3 members). Group size was significantly related to breeding male and female body sizes, and larger males had more breeding females and larger sized male helpers. The size of the largest female in the group was positively related to the number and sizes of secondary breeding females and female helpers. In case of multiple breeding females, these females usually divided the group's territory into sub-territories, each with its own helpers (subgroups). Interspersed between groups, independent fish were detected defending an individual shelter (4.4% of all fish). In 9% of the groups no breeding female was present. All group members participated in territory defence and maintenance, and showed submissive behaviours to larger group members. As expected, the level of between-subgroup conflicts was high compared with the level of within-subgroup conflicts. We compare these results with data available from other cooperatively breeding fishes.

Synchronizing behavior with other conspecifics has been suggested as serving a function of increased foraging efficiency. However, the potential costs associated with synchronization of behavior have rarely been studied. Adélie penguins Pygoscelis adeliae sometimes dive synchronously in small open waters surrounded by fast sea ice. We examined the diving behavior of three couples and one trio, which were observed to dive synchronously among groups of 12-47 birds for 1.7-4.5 h duration, with time-depth recorders. Timing of diving and surfacing differed slightly between individuals, and one bird tended to initiate diving earlier than the other. Although the duration of the dives differed only slightly between these birds, the maximum depth of the dives differed to a large extent, with one member tending to dive consistently deeper than the other bird in two out of the four cases. Vertical distances between tagged birds in the undulatory phases of the dives (presumed feeding time) were greater than those in the descent and ascent phases, suggesting independent foraging by group members. Duration of the undulatory phase of the dives tended to be shorter in deeper-diving individuals than the others in the synchronously diving group, suggesting a potential cost of reduced feeding time to synchronize diving and surfacing with other birds. A digital video image relating to the article is available at http://www.momo-p.com/ showdetail-e.php?movieid=momo030605pa01a.

We tested the response of wild American mink (an established alien species in the UK), to the odours of unfamiliar mink, European polecat and Eurasian otter. Polecats are similar in size and habits to mink, otters are larger than mink and a dominant competitor; both are native to the UK and both were absent during the original colonization by mink but are now undergoing natural population recoveries. The response of mink to experimental odours was assessed by counting the numbers of tracks (footprints) on rafts treated with anal gland secretions, and compared with response to a control raft, on two rivers in the Upper Thames valley, UK. Remote video showed that the number of tracks was positively correlated with the time that mink spent investigating an odour. We found that mink were attracted to the odours of both unfamiliar mink and polecats. There was little evidence that mink avoided the odour of otters. We suggest that, during an encounter with a polecat, mink may behave much as they would to a conspecific. We infer from the response of mink to the odour of otters, that, if mink do avoid otters, the mechanism of avoidance is likely to be complex, situation-dependent and perhaps affected by prior experience.

Participation of the Nasonov scent in the defence waving behaviour ofApis dorsata is demonstrated. The hasonov scent seems to act as a superior pheromone for the control and promotion of individual defensive reaction, synchronizing and maximizing the defensive response o n colony level. The role of Nasonov scenting in defensive behaviour is discussed, being in keeping with its usual role in attraction and coordination of social Lehar wur, as known from A. meL&ra.

En el presente trabajo se busca pulir las técnicas de observación y registro dictadas durante el curso de comportamiento de chimpancés en cautiverio, con el fin de establecer los aspectos del comportamiento de estos primates que permitan contemplar su mantenimiento a largo plazo en los zoológicos.
Vamos a centrarnos en las características más salientes del recinto que habitan, y como se relacionan con él y con sus cuidadores. La idea es ver qué aspectos de esta relación pueden mejorarse en el futuro con el objetivo de mejorar el bienestar animal, a través de técnicas de enriquecimiento ambiental.

Κυβερνητική, Περισκόπιο της επιστήμης, Ιούλ-Αυγ. 1984, τ. 67, σελ. 55-61. Δημοσιεύτηκε και σαν επίμετρο στο βιβλίο μου «Η αναγκαιότητα του μύθου». Τι είναι Κυβερνητική; Η τέχνη της αποτελεσματικότητας της δράσης, λέει ένας ορισμός που προτείνει ο Λουί Κουφινιάλ. Η σωστή αξιοποίηση της πληροφορίας καθώς και οι ηλεκτρονικοί υπολογιστές συμβάλλουν σ' αυτή την αποτελεσματικότητα. Όμως πώς ενσωματώνονται στην κυβερνητική προσέγγιση των προβλημάτων; Στο άρθρο αυτό γίνεται προσπάθεια να δοθεί μια απάντηση. Η ετυμολογία της λέξης δεν είναι δύσκολη για τον Έλληνα αναγνώστη, όμως είναι ελάχιστα διασαφητική για το περιεχόμενό της. Ο μέσος αναγνώστης, όταν ακούει τη λέξη «Κυβερνητική», φέρνει στο νου του ηλεκτρονικούς υπολογιστές, και ίσως τις έννοιες της επικοινωνίας, του ελέγχου και του feed back. Όμως πώς σχετίζονται όλες αυτές οι έννοιες με την «κυβερνητική;» Στο άρθρο μας αυτό θα προσπαθήσουμε να δώσουμε ένα διαγραμματικό σκελετό για το τι συνιστά την κυβερνητική και πώς διαρθρώνονται πάνω της οι παραπάνω έννοιες. «Η Κυβερνητική αναφέρεται ιδιαίτερα στα αυτορρυθμιζόμενα ή προσαρμοστικά συστήματα», αναφέρει ανάμεσα στ' άλλα ένας ορισμός της κυβερνητικής (F.H.George, Cybernetics, Hodder and Stoughton, 1971, σελ. 3). Ο όρος αυτορρύθμιση αναφέρεται σε μηχανές, ο όρος προσαρμογή σε ζωντανούς οργανισμούς. Βασικά όμως σημαίνουν το ίδιο πράγμα. Εμείς θα μελετήσουμε τις αρχές αυτές στους ζωντανούς οργανισμούς, απ' όπου τις πήρε ο άνθρωπος για να τις εφαρμόσει σε μηχανικά συστήματα. Μια βασική ιδιότητα της ύλης είναι η τάση για σταθερότητα. Η τάση αυτή μάς οδηγεί κατευθείαν στην έννοια της «δομής». Μόνο μονάδες που διαθέτουν μιαν ορισμένη δομή διακρίνονται και για κάποια σταθερότητα. Η έννοια της δομής εξάλλου αποτελεί μια βασική ταξινομική αρχή. Η δομή του ατόμου ενός στοιχείου είναι που καθορίζει τις ιδιότητές του, και με βάση αυτή καταλαμβάνει την ιδιαίτερη θέση του στο περιοδικό σύστημα των στοιχείων. Η σταθερότητα της δομής ενός στοιχείου είναι βέβαια σχετική. Σε φυσικές συνθήκες τα άτομα ορισμένων στοιχείων χάνουν ηλεκτρόνια της εξωτερικής τους στιβάδας και έτσι μετατρέπονται σε ιόντα. Σε συνθήκες υψηλών θερμοκρασιών διαλύεται η δομή του ατόμου και έχουμε μόνο σωματίδια ύλης. Ένα στοιχείο που ξεχωρίζει τη ζωντανή οργανική ύλη από την ανόργανη είναι η πολυπλοκότητα της δομής. Την πολυπλοκότητα αυτήν την παρατηρούμε και στα τρία επίπεδα οργάνωσης της: α) στο επίπεδο των αμινοξέων, των στοιχειωδέστερων οργανικών ενώσεων, από τα οποία συντίθενται οι πρωτοπλασματικές ενώσεις και τα λευκώματα β) στο επίπεδο του κυττάρου, της δομικής μονάδας του οργανισμού και γ) στον ίδιο τον οργανισμό σαν πολυκυτταρική ένωση. Η δομή των ζωντανών οργανισμών, μας διδάσκει ο Piaget, είναι δυναμικής φύσης, δηλαδή περικλείει μέσα της στοιχεία που την ωθούν προς μια εξέλιξη. Η δομή της άψυχης ύλης θα μπορούσε να χαρακτηρισθεί στατική. Ένα κτίριο είναι πάντα μια ακίνητη οικοδομή. Δε συμβαίνει όμως το ίδιο μ' ένα ζωντανό οργανισμό, που η δομή του συνεχώς μεταβάλλεται. Σε μερικές μάλιστα περιπτώσεις οι αλλαγές είναι εντελώς δραματικές, όπως στην περίπτωση της κάμπιας που μεταβάλλεται σε χρυσαλλίδα. Τι είναι τώρα αυτό που κάνει έναν οργανισμό να διατηρεί την ενότητά του, παρά την εμφανή αλλαγή της δομής του; Μα η λειτουργία του. Η λειτουργία λοιπόν είναι που δίνει τη δυναμικότητά της στη δομή. Ανάμεσα στις δύο αυτές έννοιες υπάρχει μια διαλεκτική σχέση εξάρτησης και αλληλεπίδρασης. Δεν μπορούμε να φανταστούμε (σε ζωντανά συστήματα ή σε συστήματα κατασκευασμένα από άνθρωπο) δομή χωρίς λειτουργία (κίνηση), ούτε λειτουργία χωρίς δομή. Η αντίθεση είναι φαινομενική, και έχει σχέση με την ιστορική προέλευση της έννοιας της δομής, που την ταυτίζουμε με την έννοια της στατικότητας. Επειδή δε η ενότητα ενός οργανισμού ιστορικά περιγραφόταν στη βάση της δομής του, και επειδή τελευταία συνειδητοποιήθηκε ότι αναπόσπαστος όρος κάθε δομής είναι η λειτουργία της, διαμορφώθηκε η έννοια της «δυναμικής δομής» (το «δυναμική» σαν προσδιορισμός στη δομή, και όχι αντίστροφα π.χ. δομικός δυναμισμός). Τι στόχο έχει η λειτουργία; Τη διατήρηση της δομής. Πώς εξυπηρετεί η δομή; Σαν υλικό υπόστρωμα της κίνησης-λειτουργίας.

The study of marine mammals in the wild is faced with major difficulties: encounter frequency and duration are limited, individual identification is difficult, social behaviors occur mostly in murky or deep water, the ability to assign vocalizations to individuals is usually very limited, sea conditions are not always suitable for research, and the design of controlled experiments is virtually impossible. In contrast, research in captivity poses different methodological obstacles due to confined space, artificial and sometimes poor environments, forced social structure, small sample sizes, subjects that are not always good representatives of wild populations etc., all provide constant challenge to scientists. This paper reviews some of the studies on Black Sea bottlenose dolphins (Tursiopstruncatus ponticus) conducted during the 15 years since the establishment of the International Laboratory for Dolphin Behaviour Research (ILDBR) located at the semi-natural Dolphin-Reef (Eilat, Isr...

The welfare of captive bears Behavioural disorders that are found in bears kept in zoos comprise a commonly encountered problem around the world. Its occurrence is common in bears kept in conditions that are not appropriate. Captive bears live for a relatively long time, which can give a misleading impression that they do not have many physical or psychological needs. Meanwhile, the recent research has established and explicitly indicated high cognitive abilities of these animals, comparable to primates. Recent progress in our knowledge base has made it possible to recognize the needs of all bear species and to maintain appropriate levels of their welfare.

Moonlight is known to affect the nocturnal behaviour and activity rhythms of many organisms. For instance, predators active at night may take advantage from increased visibility afforded by the moon, while prey might regulate their activity patterns to become less detectable. Many species of pelagic seabirds attend their colony only at night, in complete darkness, avoiding approaching their nest sites under moonlight. This behaviour has been most often interpreted as an antipredator adaptation ('predation avoidance' hypothesis). However, it may also reflect a lower foraging efficiency during moonlit nights ('foraging efficiency' hypothesis). Indeed, moonlight may reduce prey availability because preferred seabird prey is known to occur at higher depths in moonlit nights. Using high-accuracy behavioural information from data loggers, we investigated the effect of moonlight on colony attendance and at-sea nocturnal foraging in breeding Scopoli's shearwaters Calonectris diomedea. We found that birds departing for self-feeding trips around the full moon performed longer trips than those departing around the new moon. On nights when the moon was present only partly, nest burrow entrances took place largely in the moonless portion of the night. Moreover, contrary to predictions from the 'foraging efficiency' hypothesis, nocturnal foraging activity increased according to moonlight intensity, suggesting that birds increased their foraging activity when prey became more detectable. This study strengthens the idea that colony attendance behaviour is strictly controlled by moonlight in shearwaters, which is possibly related to the perception of a predation risk.

Dai tempi di Aristotele fino alla prima metà del Novecento, occuparsi di fenomeni culturali, studiare culture passate o esistenti, ricostruirne la storia e analizzarne linguaggi, produzioni e tradizioni ha significato occuparsi esclusivamente di culture umane, e l’uomo è stato considerato l’unico “animale culturale”. Oggi, a poco più di mezzo secolo dall’inizio di quella rivoluzione scientifica che, negli anni Sessanta, condusse alla scoperta dell’esistenza di tradizioni e usi differenziati in varie specie di primati, cetacei e uccelli, anche se l’etologia culturale è disciplina ancora giovanissima, possiamo considerare ampiamente riscontrata l’ipotesi dell’esistenza di culture non umane, e altamente probabile che tutte le specie di mammiferi e uccelli sociali esistenti abbiano sviluppato al proprio interno, da milioni di anni, diverse tradizioni comportamentali e comunicative.1 Sappiamo, altresì, che tali differenziazioni degli usi, tramandate attraverso l’apprendimento sociale in diverse popolazioni di una medesima specie, non sono prerogativa esclusiva di mammiferi e uccelli. Ricerche svolte negli ultimi quaranta anni hanno evidenziato l’esistenza di tradizioni locali intraspecifiche in varie spe
1Come vengono definiti oggi i concetti di “cultura” e “tradizione” in ambito etologico? “Chiamiamo «tratti culturali» quei modelli di comportamento condivisi da membri di popolazioni animali che dipendono in qualche misura da apprendimenti socialmente mediati e informazioni socialmente trasmesse. Chiamiamo «variazione culturale» quelle differenze fenotipiche tra individui, osservate all’interno di, o tra, popolazioni, che sono in qualche misura, attribuibili a differenze socialmente apprese. Usiamo i termini «tradizione» e «cultura» come sinonimi»” (Laland, Kendal, Kendal 2009, pp. 178, 179; traduzione mia).
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ANIMAL STUDIES 26 cie di pesci teleostei, in particolare tra specie delle grandi barriere coralline (Helfman, Schulz 1984; Bshary, Wickler 2002; Laland, Atton, Webster 2011), e ciò fa pensare che fenomeni analoghi potrebbero essere riscontrabili in tutti i vertebrati acquatici e terrestri, che dai pesci ossei derivano.

Predator mobbing has been viewed as an adaptation to reduce the risk of predation, however, factors influencing mobbing behaviour are still debated. We report on the results of an experiment with Dendroica caerulescens and Dendroica virens designed to determine (1) whether mobbing response by forest songbirds during the breeding season is restricted by territory boundaries, (2) the distance songbirds will move in response to anti-predator mobbing calls, and (3) whether reproductive status, age, and time of the breeding season determine the distance moved to mob. We did not detect an effect of reproductive status, age, or time of breeding season on the distance moved by birds to mob. All birds responded to the mobbing playback within their territory (defined by territorial defence in relation to specific song playbacks). The maximum distance moved within a territory to engage in mobbing ranged from 25 to 175 m ( x ¼ 72 ± 6 m). Three of 37 birds responded to playbacks outside their territory boundaries. In all three cases, maximum movement distances outside territories were short (25 m). Thus, for two species of warblers, mobbing is highly constrained by territory boundaries during the breeding season. This finding is congruent with arguments that mobbing is primarily a selfish behaviour, at least with respect to conspecifics. Our results also provide support for the Ômove-onÕ hypothesis.

Le società animali presentano un’incredibile molteplicità di articolazioni sistemiche e strutturali, tese a regolare le dinamiche interattive, comunicative, affiliative che si vengono a creare e che inevitabilmente richiedono predicati funzionali specifici. Quando parliamo di comportamenti prosociali intendiamo una varietà di espressioni, non necessariamente attribuibili a una medesima famiglia motivazionale o a un ciclo funzionale specifico, che si caratterizzano per il fatto di vedere l’individuo spendere delle risorse per il gruppo, sia che tale atteggiamento comporti un ritorno vantaggioso per il soggetto agente sia che sia più difficile riscontrare tale ristorno o addirittura sia palesemente in contrasto con gli interessi dell’agente. I comportamenti prosociali presentano un panorama articolato di situazioni: dalla cooperazione per raggiungere un obiettivo comune alle pragmatiche comunicative tese all’ingaggio o alla regolazione sociale, dalle espressioni epimeletiche alle offerte e agli atteggiamenti rassicuranti-protettivi che si riscontrano nel corteggiamento.

If the camera is a pen in the hand of the director, as Alexandre Astruc declared in 1948, then Austrian marine biologist, diving pioneer and filmmaker Hans Hass (1919-2013) is a candidate for auteur status. Not only was Hass the producer, director and co-cinematographer of three successful theatrical features between 1947 and 1954 and a twenty-six part television series for German state broadcaster Südwestfunk and the BBC between 1958 and 1962. Hass also built his own pens, or pencils. While he earns no mention in two recent North American studies of subaquatic cinematography,  historian of science David Chapman insists that the scientific work of Hans Hass during the 1940s, alongside that of Jacques-Yves Cousteau, “was key in progressing both sub-aqua breathing and swimming equipment, as well as the design and commissioning of underwater housing for cinematic cameras”  – the technical equipment that allowed Hass to produce the underwater footage that made him an international celebrity in the 1950s. Yet despite his scientific and technological prowess and artistic control, in the title sequence of his 1950 theatrical film Adventures in the Red Sea which chronicles a scientific expedition on a sailboat in the Red Sea, Hass delegates the authorship of his film to forces much larger than himself. The two main credits read “Chance Wrote the Screenplay, Reality Directed the film” (“Drehbuchautor war der Zufall, Regisseur war die Wirklichkeit”). Not unlike Bazin in his 1945 essay on the ontology of the photographic image, the credit line claims that reality and chance can express themselves through film without any significant contribution from an artist. But reality and chance still need the conduit of technology. They need the instruments of what historian of technology Franziska Torma, in her work on subaquatic cinematography, describes as “mechanical exploration,” a type of exploration in which technology is instrumental to the process of discovery.  In this sense, “Chance Wrote Screenplay, Reality Directed the Film” offers a shorthand for what we might call an aesthetics of nature bounded by technologies of exploration.
In what follows, I want to explore Hass’ technologically bounded aesthetics of nature by situating his films within the “culture of exploration” of the long 19th century, in which according to historian Felix Driver “the boundaries between scientific exploration and adventure travel, the sober and the sensational, or the analytical and the aesthetic” are never secure but “always in the process of construction.

Современный город как местообитание «диких» видов птиц и других животных, освоивших урболандшафт, играет крайне противоречивую и двойственную роль.
С одной стороны, для любого дикого вида это предельно экстремальная среда обитания, и преадаптированные виды можно пересчитать по пальцам. Даже если виды находят в городе аналоги естественных местообитаний, они настолько фрагментированы, нарушены и нестабильны во времени и пространстве, как это никогда не бывает в природе. И всем без исключения видам, осваивающим урбосреду – от скопы и сапсана до зарянок, соловьёв и варакушек приходится приспосабливаться к такой нестабильности и изменчивости среды, как общему для всех лимитирующему барьеру при создании городских популяций. Дикие виды привыкли жить в непрерывных местообитаниях и даже умеренная фрагментации лесов ведёт к сокращению численности и исчезновению многих видов, в городе им приходится «прыгать со льдины на льдину», оперативно перебрасывая население вида с одного «острова» местообитаний на другой, чтоб поспеть за постоянными сдвигами кружева биотопов в ходе эволюции урболандшафта.
В книге рассматриваются тонкие эколого-этологические механизмы, позволяющие городским популяциям сохранять устойчивость вопреки быстрым и направленным изменениям урбосреды. Показано, что всякое возрастание успешности вида в прыжках «с льдины на льдину» в специальных условиях города стимулирует попытки дальнейшей урбанизации, освоение ещё более фрагментированных и нарушенных биотопов и так далее. Процесс продолжается до тех пор, пока новорожденная городская популяции не отделится от  исходной материнской уже окончательно – как у вяхиря, чёрного дрозда, рябинника, лазоревки и прочих.
Также анализируются те трансформации популяционной системы, которые необходимы, чтобы «дикий вид», дал жизнеспособную городскую популяцию, ведь исходно необходимый уровень лабильности системы имеются не у всех, и дихотомия «консерватизм – лабильность» популяционной системы вида, первый полюс которой затрудняет, а второй – облегчает урбанизацию. Выделив факторы популяционной устойчивости вида во фрагментированных местообитаниях, проранжировав виды по способности колонизировать их экстремальный вариант (урболандшафт), мы даём прогноз перспектив урбанизации «диких видов» птиц фауны Московского региона в контексте разных сценариев развития урбанизированного ядра Большой Москвы. Показано, что рост и эволюция урбанизированного ядра региона производит отбор экологически близких видов, уже поселившихся на территории городов. В каждой паре (тройке, четвёрке) таких видов, биология которых на территории города почти идентична из-за конвергенции экологических ниш, естественная эволюция  урболандшафта производит постоянный отбор. Она содействует ещё большей урбанизации видов с более лабильной стратегией, но подрывает популяционную устойчивость и вытесняет из города более консервативные виды из группы близких (что делает их ещё более консервативными). Так сказать, имущему воздастся, у неимущего отнимется.
С другой стороны, территориальный рост городов создаёт «техногенные аналоги природных ландшафтов, уничтоженных в процессе подобного роста: пустыри и газоны вместо лугов, старые усадьбы и парки – вместо лесов, поля орошения – вместо водно-болотных угодий. Этим городское развитие содействует началу урбанизации всё новых и новых видов региональной авифауны, включая те, что были вытеснены из города на предыдущем этапе и за время пребывания «под прессом» урбанизированного ядра достаточно лабилизировали популяционную структуру для начала успешной урбанизации.
Показано, что наличное разнообразие авифауны крупных городов определяется балансом первого и второго процессов вытеснения и урбанизации, связанных с обретением и потерей устойчивости популяционной системы вида в ходе эволюции урболандшафта, и не зависит от экологической вместимости городских местообитаний, которая всегда избыточна. Проблема в том, чтобы вовремя нужные участки найти и на них размножиться нужному числу особей, а для этого нужна лабильная структура отношений в системе, тем не менее не выходящая за пределы видовой нормы, более разболтанная и с большей свободой комбинирования вариантов, но на же «конструкция» популяционной системы вида.
Наконец, на основе представлений о популяционной устойчивости как главного эволюционного достижения вида в процессе урбанизации (а не адаптации к специфическим городским биотопам) объяснены экологические парадоксы последней.
С одной стороны, городские местообитания снимают ресурсные ограничения на число видов, способных одновременно жить на одной территории, городские местообитания содержат заведомый избыток ресурсов. Однако в городах увеличивается число случаев вытеснения одного вида другим, то есть конкуренция вроде бы обостряется. Согласно существующей экологической теории обострение конкуренции ведёт вроде бы к разделению ниш? но именно в городских биотопах ниши близких видов конвергируют до полного безразличия. То же самое наблюдается при выпадении снега, резком похолодании, затяжных дождях и других ухудшениях погодных условий, увеличивающих «напряжение жизни» у птиц (например, снижением доступности корма). Освоение исторически нетипичного ландшафта вроде бы должно вести к быстрой морфологической эволюции особей в городских популяциях?  Но преобразуется лишь система отношений между особями, популяционная организация, а морфология индивидов остаётся в пределах нормы, изменяется их психофизиология, биологические ритмы и пр. – насколько необходимо для приспособления особей к изменившейся популяционной структуре и иной социальной среде группировок.
Двадцать лет назад, начиная исследования городской авифауны, мы считали, что город – это только угроза «диким» видам птиц в регионе, он их будет вытеснять к малонарушенной периферии, а в самом городе останутся только вороны. Сейчас мы с радостью видим, что это не так. Как всякое прогрессивное творение человека современный город даёт орнитофауне шанс «пересесть» из природных местообитаний, разрушающихся в ходе урбанизации региона под действием застройки и массовой рекреации в свои техногенные аналоги внутри разрастающегося урбанизированного ядра.
И очень жаль, что в нашем собственном городе этот шанс последовательно уничтожается ради прибылей стройкомплекса и других корыстных  интересов минуты.
В Древней Греции говорили: «Ты чурбан, коль Афин не видывал; осел, коль увидев, не пришёл в восторг; верблюд, коль покинул их, не жалуясь». Время восторгов городом как средоточием цивилизации прошло, пришло время «жалоб» на социальные и экологические проблемы. Мы надеемся, книга послужит их конструктивному разрешению в части, касающейся сохранения биоразнообразия – не только города, но и всего урбанизированного региона. Ведь регулировать рост городов мы до сих пор не умеем, а тем более сдерживать рост их «сферы влияния» - в условиях, когда зона отдыха выходного дня расползается как масляное пятно на воде вместе с поддерживающей её сетью автодорог и дачных участков, фрагментирующих биотопы не хуже урболандшафта.
В условиях экспансии «городского ядра» единственный шанс сохранения «диких» видов – их скорейшая урбанизация, поворот от «отступления» из «зоны влияния» города к направленному освоению тех (многих!) возможностей, которые создаёт урбосреда. Мы исследуем возможности и условиях этого «поворота», важного и в теоретическом, и в природоохранном отношении.