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Adamo, S. A., Ehgoetz, K., Sangster, C., & Whitehorne, I. (2006). Signaling to the Enemy? Body Pattern Expression and Its Response to External Cues During Hunting in the Cuttlefish Sepia officinalis (Cephalopoda). Biol. Bull., 210(3), 192–200.
Abstract: Abstract. Cuttlefish can rapidly alter their appearance by using neurally controlled chromatophore organs. This ability may provide a window into their cognitive capacity. We test whether the changes in body pattern that occur during hunting depend on context. If they do, then it may be possible to use these changes to study cephalopod cognition while the animal is engaged in ecologically relevant tasks. We found consistent individual differences in the tendency of cuttlefish to hunt with the first two arms raised. We also found that cuttlefish usually darken their skin after they seize a prey item. This darkening is observed regardless of the identity of the prey (fish, crab, or shrimp), prey context (buried in sand, in a bare tank, or on top of a rock pile), or the presence of a sudden stimulus. The sudden stimulus was created by presenting an overhead model bird to the cuttlefish. The model induced components of the Deimatic Display, which is a form of antipredator behavior, suggesting that the model was perceived as a potential threat. Passing Cloud displays and the Darkening of the arms were significantly reduced after exposure to the model bird. The effect of a potential predator on body pattern expression during hunting suggests it may be possible to use these changes as a sensitive indicator of ecologically relevant learning. N1 -
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Allen, C. (2006). Transitive inference in animals: Reasoning or conditioned associations? In S. Hurley, & M. Nudds (Eds.), Rational Animals? (pp. 175–186). Oxford: Oxford University Press.
Abstract: It is widely accepted that many species of nonhuman animals appear to engage in transitive inference,
producing appropriate responses to novel pairings of non-adjacent members of an ordered series
without previous experience of these pairings. Some researchers have taken this capability as
providing direct evidence that these animals reason. Others resist such declarations, favouring instead
explanations in terms of associative conditioning. Associative accounts of transitive inference have
been refined in application to a simple 5-element learning task that is the main paradigm for
laboratory investigations of the phenomenon, but it remains unclear how well those accounts
generalise to more information-rich environments such as social hierarchies which may contain scores
of individuals, and where rapid learning is important. The case of transitive inference is an example of
a more general dispute between proponents of associative accounts and advocates of more cognitive
accounts of animal behaviour. Examination of the specific details of transitive inference suggests
some lessons for the wider debate.
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Amdam, G. V., Csondes, A., Fondrk, M. K., & Page, R. E. J. (2006). Complex social behaviour derived from maternal reproductive traits. Nature, 439(7072), 76–78.
Abstract: A fundamental goal of sociobiology is to explain how complex social behaviour evolves, especially in social insects, the exemplars of social living. Although still the subject of much controversy, recent theoretical explanations have focused on the evolutionary origins of worker behaviour (assistance from daughters that remain in the nest and help their mother to reproduce) through expression of maternal care behaviour towards siblings. A key prediction of this evolutionary model is that traits involved in maternal care have been co-opted through heterochronous expression of maternal genes to result in sib-care, the hallmark of highly evolved social life in insects. A coupling of maternal behaviour to reproductive status evolved in solitary insects, and was a ready substrate for the evolution of worker-containing societies. Here we show that division of foraging labour among worker honey bees (Apis mellifera) is linked to the reproductive status of facultatively sterile females. We thereby identify the evolutionary origin of a widely expressed social-insect behavioural syndrome, and provide a direct demonstration of how variation in maternal reproductive traits gives rise to complex social behaviour in non-reproductive helpers.
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Amé, J. - M., Halloy, J., Rivault, C., Detrain, C., & Deneubourg, J. L. (2006). Collegial decision making based on social amplification leads to optimal group formation. Proc. Natl. Acad. Sci. U.S.A., 103(15), 5835–5840.
Abstract: Group-living animals are often faced with choosing between one or more alternative resource sites. A central question in such collective decision making includes determining which individuals induce the decision and when. This experimental and theoretical study of shelter selection by cockroach groups demonstrates that choices can emerge through nonlinear interaction dynamics between equal individuals without perfect knowledge or leadership. We identify a simple mechanism whereby a decision is taken on the move with limited information and signaling and without comparison of available opportunities. This mechanism leads to optimal mean benefit for group individuals. Our model points to a generic self-organized collective decision-making process independent of animal species.
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Apple, J. K., Kegley, E. B., Galloway, D. L., Wistuba, T. J., Rakes, L. K., & Yancey, J. W. S. (2006). Treadmill exercise is not an effective methodology for producing the dark-cutting condition in young cattle. J. Anim Sci., 84(11), 3079–3088.
Abstract: Holstein steer calves (n = 25) were used to evaluate the effects of treadmill exercise (TME) on blood metabolite status and formation of dark-cutting beef. Calves were blocked by BW (156 {+/-} 33.2 kg) and assigned randomly within blocks to 1 of 5 TME treatments arranged in a 2 x 2 factorial design (4 or 8 km/h for a duration of 10 or 15 min) with a nonexercised control. Venous blood was collected via indwelling jugular catheters at 10, 2, and 0 min before TME and at 2-min intervals during exercise. Nonexercised steers were placed on the treadmill but stood still for 15 min. Serum cortisol levels, as well as plasma concentrations of glucose, lactate, and NEFA, were similar (P > 0.05) before TME. Serum cortisol concentrations were unaffected (P > 0.05) during the first 6 min of TME, but between 8 and 15 min of TME, cortisol concentrations were greater (P < 0.05) in steers exercised at 8 km/h than those exercised at 4 km/h or controls (speed x time, P < 0.001). Although TME did not affect (P > 0.05) plasma glucose levels, plasma lactate concentrations in steers exercised at 8 km/h increased (P < 0.05) sharply with the onset of the TME treatment and remained elevated compared with steers exercised at 4 km/h or unexercised controls (speed x time, P < 0.001). Exercised steers had the lowest (P < 0.05) plasma NEFA concentrations during the first 6 min of TME compared with unexercised steers; however, NEFA concentrations were similar after 10 and 12 min of TME, and by the end of TME, steers exercised at 8 km/h had greater (P < 0.05) NEFA levels than nonexercised controls or steers exercised at 4 km/h (speed x time, P < 0.001). Even though muscle glycogen levels and pH decreased (P < 0.001) and muscle lactate concentrations increased (P < 0.001) with increasing time postmortem, neither treadmill speed nor TME duration altered postmortem LM metabolism. Consequently, there were no (P > 0.05) differences in the color, water-holding capacity, shear force, or incidences of dark-cutting carcasses associated with preslaughter TME. It is apparent that preslaughter TME, at the speeds and durations employed in this study, failed to alter antemortem or postmortem muscle metabolism and would not be a suitable animal model for studying the formation of the dark-cutting condition in ruminants.
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Arnold, K., & Zuberbuhler, K. (2006). Language evolution: semantic combinations in primate calls. Nature, 441(7091), 303.
Abstract: Syntax sets human language apart from other natural communication systems, although its evolutionary origins are obscure. Here we show that free-ranging putty-nosed monkeys combine two vocalizations into different call sequences that are linked to specific external events, such as the presence of a predator and the imminent movement of the group. Our findings indicate that non-human primates can combine calls into higher-order sequences that have a particular meaning.
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Arnold, W., Ruf, T., & Kuntz, R. (2006). Seasonal adjustment of energy budget in a large wild mammal, the Przewalski horse (Equus ferus przewalskii) II. Energy expenditure. J Exp Biol, 209(Pt 22), 4566–4573.
Abstract: Many large mammals show pronounced seasonal fluctuations of metabolic rate (MR). It has been argued, based on studies in ruminants, that this variation merely results from different levels of locomotor activity (LA), and heat increment of feeding (HI). However, a recent study in red deer (Cervus elaphus) identified a previously unknown mechanism in ungulates--nocturnal hypometabolism--that contributed significantly to reduced energy expenditure, mainly during late winter. The relative contribution of these different mechanisms to seasonal adjustments of MR is still unknown, however. Therefore, in the study presented here we quantified for the first time the independent contribution of thermoregulation, LA and HI to heart rate (f(H)) as a measure of MR in a free-roaming large ungulate, the Przewalski horse or Takhi (Equus ferus przewalskii Poljakow). f(H) varied periodically throughout the year with a twofold increase from a mean of 44 beats min(-1) during December and January to a spring peak of 89 beats min(-1) at the beginning of May. LA increased from 23% per day during December and January to a mean level of 53% per day during May, and declined again thereafter. Daily mean subcutaneous body temperature (T(s)) declined continuously during winter and reached a nadir at the beginning of April (annual range was 5.8 degrees C), well after the annual low of air temperature and LA. Lower T(s) during winter contributed considerably to the reduction in f(H). In addition to thermoregulation, f(H) was affected by reproduction, LA, HI and unexplained seasonal variation, presumably reflecting to some degree changes in organ mass. The observed phase relations of seasonal changes indicate that energy expenditure was not a consequence of energy uptake but is under endogenous control, preparing the organism well in advance of seasonal energetic demands.
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Aust, U., & Huber, L. (2006). Picture-object recognition in pigeons: evidence of representational insight in a visual categorization task using a complementary information procedure. J Exp Psychol Anim Behav Process, 32(2), 190–195.
Abstract: Success in tasks requiring categorization of pictorial stimuli does not prove that a subject understands what the pictures stand for. The ability to achieve representational insight is by no means a trivial one because it exceeds mere detection of 2-D features present in both the pictorial images and their referents. So far, evidence for such an ability in nonhuman species is weak and inconclusive. Here, the authors report evidence of representational insight in pigeons. After being trained on pictures of incomplete human figures, the birds responded significantly more to pictures of the previously missing parts than to nonrepresentative stimuli, which demonstrates that they actually recognized the pictures' representational content.
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Balakrishnan, G., Hu, Y., & Spiro, T. G. (2006). Temperature-jump apparatus with Raman detection based on a solid-state tunable (1.80-2.05 microm) kHz optical parametric oscillator laser. Appl Spectrosc, 60(4), 347–351.
Abstract: The operating characteristics of a pulsed (10 ns) tunable near-infrared (NIR) laser source are described for temperature-jump (T-jump) applications. A Q-switched Nd:YLF laser (approximately 10 ns pulses) with a 1 kHz repetition rate is used to pump a potassium titanyl arsenate (KTA) crystal-based optical parametric oscillator (OPO), producing approximately 1 mJ NIR pulses that are tunable (1.80-2.05 microm) across the 1.9 microm vibrational overtone band of water. This T-jump source has been coupled to a deep ultraviolet (UV) probe laser for Raman studies of protein dynamics. T-jumps of up to 30 degrees C, as measured via the O-H stretching Raman band of water, are readily achieved. Application to cytochrome c unfolding is demonstrated.
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Balenghien, T., Fouque, F., Sabatier, P., & Bicout, D. J. (2006). Horse-, bird-, and human-seeking behavior and seasonal abundance of mosquitoes in a West Nile virus focus of southern France. J Med Entomol, 43(5), 936–946.
Abstract: After 35 yr of disease absence, West Nile virus (family Flaviviridae, genus Flavivirus, WNV) circulation has been regularly detected in the Camargue region (southern France) since 2000. WNV was isolated from Culex modestus Ficalbi, which was considered the main vector in southern France after horse outbreaks in the 1960s. Recent WNV transmissions outside of the Cx. modestus distribution suggested the existence of other vectors. To study potential WNV vectors, horse- and bird-baited traps and human landing collections of mosquitoes were carried out weekly from May to October 2004 at two Camargue sites: one site in a wet area and the other site in a dry area, both chosen for their past history of WNV transmission. At the wet site, the most abundant species in bird-baited traps were Culex pipiens L. and Cx. modestus; both species also were found in lower proportions on horses and humans. The most abundant species in horse-baited traps and human landing collections were Aedes caspius (Pallas), Aedes vexans (Meigen), and Anopheles hyrcanus (Pallas) sensu lato; some of these species were occasionally collected with avian blood at the end of the summer. Anopheles maculipennis Meigen sensu lato was an abundant horse feeder, but it was rarely collected landing on human bait and never contained avian blood. At the dry site, Cx. pipiens was the most abundant species in bird- and horse-baited traps. The seasonal and circadian dynamics of these species are analyzed, and their potential in WNV transmission in Camargue discussed.
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