Abstract: Animals process sensory information according to specific computational rules and, subsequently, form representations of their environments that form the basis for decisions and choices. The specific computational rules used by organisms will often be evolutionarily adaptive by generating higher probabilities of survival, reproduction, and resource acquisition. Experiments with enclosed colonies of bumblebees constrained to foraging on artificial flowers suggest that the bumblebee's cognitive architecture is designed to efficiently exploit floral resources from spatially structured environments given limits on memory and the neuronal processing of information. A non-linear relationship between the biomechanics of nectar extraction and rates of net energetic gain by individual bees may account for sensitivities to both the arithmetic mean and variance in reward distributions in flowers. Heuristic rules that lead to efficient resource exploitation may also lead to subjective misperception of likelihoods. Subjective probability formation may then be viewed as a problem in pattern recognition subject to specific sampling schemes and memory constraints.

Abstract: Individual recognition is considered a complex process and, although it is believed to be widespread across animal taxa, the cognitive mechanisms underlying this ability are poorly understood. An essential feature of individual recognition in humans is that it is cross-modal, allowing the matching of current sensory cues to identity with stored information about that specific individual from other modalities. Here, we use a cross-modal expectancy violation paradigm to provide a clear and systematic demonstration of cross-modal individual recognition in a nonhuman animal: the domestic horse. Subjects watched a herd member being led past them before the individual went of view, and a call from that or a different associate was played from a loudspeaker positioned close to the point of disappearance. When horses were shown one associate and then the call of a different associate was played, they responded more quickly and looked significantly longer in the direction of the call than when the call matched the herd member just seen, an indication that the incongruent combination violated their expectations. Thus, horses appear to possess a cross-modal representation of known individuals containing unique auditory and visual/olfactory information. Our paradigm could provide a powerful way to study individual recognition across a wide range of species.

Abstract: Aggressive contests probably occur in networking environments where information about fighting ability is conveyed both to an opponent and to individuals peripheral to the fight itself, the bystanders. Our primary aim was to investigate the relative influences of eavesdropping and prior social experience on the dynamics of aggressive contests in Xiphophorus helleri. A bystander's ability to witness an encounter was manipulated using clear, one-way mirror, and opaque partitions. After watching (or not watching) the initial contest, the bystander encountered either the winner or loser of the bout. Treatment comparisons of bystander-winner or bystander-loser contest dynamics indicated the presence or absence of winner, loser, or eavesdropping effects. Winner and loser effects had negligible influences on bystander contest dynamics. Eavesdropping significantly reduced the bystander's propensity to initiate aggression, escalate, and win against seen winners regardless of whether the watched bout had escalated or not. Though eavesdropping had relatively little effect on bystander-loser contest dynamics, bystanders were less prone to initiate aggression and win against losers that had escalated in the witnessed bout. Thus, bystanders appear to preferentially retain and utilize information gained about potentially dangerous opponents (winners or persistent losers). Our data lend clear support for the importance of eavesdropping in visually based aggressive signalling systems.

Abstract: The landing patterns of horse flies on the human body were observed in Croatia. A total of 386 horse flies belonging to 22 species were sampled. The five most commonly collected species were used in the analysis. The stochastic linear connection is tight among the landings of the species Tabanus bromius, Tabanus maculicornis, Tabanus tergestinus, and Philipomyia graeca on the human body regions (matrix R). The preferred feeding area for these four species was the lower leg, whereas for the species Haematopota pluvialis it was the head and neck. Of the total number of horse flies that landed 44.81% were on the lower leg. Only 0.26% landed on the forearm. Chi-square analysis indicated non random landing patterns on human by these horse flies.

Abstract: Reconciliation, defined as a friendly reunion between former opponents shortly after an aggressive encounter, is common in the stumptail macaque (Macaca arctoides) but rare in the rhesus macaque (M. mulatta). Juveniles of the two species were cohoused for 5 months, after which they were observed with conspecifics only. Control rhesus monkeys, matched in age and sex to the experimental subjects, went through the same procedure without exposure to the other species. A threefold increase in the proportion of reconciled fights was measured in the rhesus subjects. The difference emerged gradually during cohousing with the tutor species and was sustained following removal of this species. Other behavior, such as grooming and aggression, decreased over time. It is suggested that the social attitude of the subjects was affected through contact with a species characterized by a more relaxed dominance style.