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Boersma, P., & Weenink, D. (2009). Praat: doing phonetics by computer.
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Ohtsuki, H., Iwasa, Y., & Nowak, M. A. (2009). Indirect reciprocity provides only a narrow margin of efficiency for costly punishment. Nature, 457(7225), 79–82.
Abstract: Indirect reciprocity1, 2, 3, 4, 5 is a key mechanism for the evolution of human cooperation. Our behaviour towards other people depends not only on what they have done to us but also on what they have done to others. Indirect reciprocity works through reputation5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17. The standard model of indirect reciprocity offers a binary choice: people can either cooperate or defect. Cooperation implies a cost for the donor and a benefit for the recipient. Defection has no cost and yields no benefit. Currently there is considerable interest in studying the effect of costly (or altruistic) punishment on human behaviour18, 19, 20, 21, 22, 23, 24, 25. Punishment implies a cost for the punished person. Costly punishment means that the punisher also pays a cost. It has been suggested that costly punishment between individuals can promote cooperation. Here we study the role of costly punishment in an explicit model of indirect reciprocity. We analyse all social norms, which depend on the action of the donor and the reputation of the recipient. We allow errors in assigning reputation and study gossip as a mechanism for establishing coherence. We characterize all strategies that allow the evolutionary stability of cooperation. Some of those strategies use costly punishment; others do not. We find that punishment strategies typically reduce the average payoff of the population. Consequently, there is only a small parameter region where costly punishment leads to an efficient equilibrium. In most cases the population does better by not using costly punishment. The efficient strategy for indirect reciprocity is to withhold help for defectors rather than punishing them.
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Harrison, S. A., & Tong, F. (2009). Decoding reveals the contents of visual working memory in early visual areas. Nature, 458(7238), 632–635.
Abstract: Visual working memory provides an essential link between perception and higher cognitive functions, allowing for the active maintenance of information about stimuli no longer in view1, 2. Research suggests that sustained activity in higher-order prefrontal, parietal, inferotemporal and lateral occipital areas supports visual maintenance3, 4, 5, 6, 7, 8, 9, 10, 11, and may account for the limited capacity of working memory to hold up to 3–4 items9, 10, 11. Because higher-order areas lack the visual selectivity of early sensory areas, it has remained unclear how observers can remember specific visual features, such as the precise orientation of a grating, with minimal decay in performance over delays of many seconds12. One proposal is that sensory areas serve to maintain fine-tuned feature information13, but early visual areas show little to no sustained activity over prolonged delays14, 15, 16. Here we show that orientations held in working memory can be decoded from activity patterns in the human visual cortex, even when overall levels of activity are low. Using functional magnetic resonance imaging and pattern classification methods, we found that activity patterns in visual areas V1–V4 could predict which of two oriented gratings was held in memory with mean accuracy levels upwards of 80%, even in participants whose activity fell to baseline levels after a prolonged delay. These orientation-selective activity patterns were sustained throughout the delay period, evident in individual visual areas, and similar to the responses evoked by unattended, task-irrelevant gratings. Our results demonstrate that early visual areas can retain specific information about visual features held in working memory, over periods of many seconds when no physical stimulus is present.
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John L. Orrock, & Brent J. Danielson. (2009). Temperature and Cloud Cover, but Not Predator Urine, Affect Winter Foraging of Mice. Ethology, 115(7), 641–648.
Abstract: Although homeotherms likely experience costs of both predation risk and thermoregulation while foraging, it is unclear how foragers contend with these costs. We used foraging trays placed in sheltered microsites to determine whether temperature, a direct cue of predator presence (predator urine) and an indirect cue of predation risk (cloudy nights) affect foraging of white-footed mice, Peromyscus leucopus, in winter. Mice were presented with urine from bobcats, Lynx rufus, red foxes, Vulpes vulpes, and coyotes, Canis latrans, an herbivore (whitetailed deer, Odocoileus virginianus), and a water control. To measure rodent foraging, we used seeds of millet mixed with sand to quantify giving-up densities (the number of seeds left in each foraging tray). Giving-up density was not affected by predator urine. Rather, rodent foraging was affected by an interaction of temperature and weather. On overcast nights, when predation risk was likely lower, mice foraged more when soil temperature was higher, presumably reducing thermoregulatory costs. On clear nights, foraging was low regardless of soil temperature, presumably because foraging was more risky. These results suggest that mice consider thermoregulatory costs and predation risk when making foraging decisions, and that the indirect cue afforded by weather, rather than the direct cue of predator urine, is among the cues used to make foraging decisions. Moreover, these results suggest that sensitivity to a particular cue is likely to be context-dependent.
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Lepple, N. (2009). Qualitätssicherung in der Fohlenaufzucht. Diploma thesis, Hochschule für Wirtschaft und Umwelt Nürtingen-Geislingen, Nürtingen.
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Clutton-Brock, T. (2009). Cooperation between non-kin in animal societies. Nature, 462(7269), 51–57.
Abstract: Explanations of cooperation between non-kin in animal societies often suggest that individuals exchange resources or services and that cooperation is maintained by reciprocity. But do cooperative interactions between unrelated individuals in non-human animals really resemble exchanges or are they a consequence of simpler mechanisms? Firm evidence of reciprocity in animal societies is rare and many examples of cooperation between non-kin probably represent cases of intra-specific mutualism or manipulation.
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Spengler, A. E., H. (2009). Human interaction with a gorilla family.
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Bundesministerium für Ernährung, L. und V. (2009). Beurteilung von Pferdehaltungen unter Tierschutzgesichtspunkten.
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Fabritius, C. (2009). Sozialstruktur einer Herde Islandpferde bei Veränderung der Gruppenzusammenstellung. Ph.D. thesis, , Hannover.
Abstract: Die Domestikation des Pferdes begann wahrscheinlich etwa 5500 v. Chr. in
Südosteuropa. In Mitteleuropa traten circa 3000 v. Chr. die ersten Hauspferde auf.
Grundsätzlich wird davon ausgegangen, dass sich die Ansprüche des Pferdes
hinsichtlich der Lebensbedingungen, welche sich im Laufe der Evolution über
Millionen von Jahren entwickelt haben, in der Obhut des Menschen nicht wesentlich
geändert haben. Für Pferde typisch ist das Leben im Sozialverband, der Herde
(Zeitler-Feicht 2008). Diese wird auch in den Leitlinien der Sachverständigengruppe
tierschutzgerechte Pferdehaltung (10. November 1995) empfohlen, sofern es nicht
durch zu häufigen Wechsel im Bestand zu einem Übermaß an Stress und
agonistischen Aktionen kommt.
Ziel der Arbeit war es, anhand eines nach der Literatur erstellten Ethogramms des
Sozialverhaltens des Pferdes, herauszufinden, inwieweit Änderungen der
Gruppenstruktur die sozialen Beziehungen beeinflussten. Die Fragestellung bezog
sich auf eine Herde in Offenstallhaltung. Um die eventuellen Veränderungen der
sozialen Interaktionen zu untersuchen, wurde erst die vorhandene Gruppenstruktur
der Herde festgestellt. Danach wurde ein Individuum aus der Herde entfernt und ein
anderes dazugestellt. Anschließend wurde die Gesamtgruppe in zwei Untergruppen
geteilt und nach einem gewissen Zeitraum erneut zusammengeführt. Dabei wurden
jeweils die Interaktionen der Pferde anhand des Ethogramms beobachtet,
aufgezeichnet und protokolliert.
Untersuchungsgegenstand war eine Herde Islandpferde, die in einer
Ausgangsgruppe von 16 Tieren gehalten wurde.
Die Beschreibung einer sozialen Ordnung im Allgemeinen und einer Rangordnung im
Besonderen wird in vielen Studien ausschließlich auf der Basis der Beobachtung und
Bewertung offensiv aggressiver Verhaltenselemente durchgeführt. Aggressives
Verhalten muss hingegen im Gegensatz zu Verhaltensweisen, die die Anerkennung
des sozialen Status des anderen Pferdes bedeuten, wie Abwenden oder Meiden,
nicht notwendigerweise ein Anzeichen von Dominanz über ein anderes Tier
bedeuten (Van Hoof u. Wensing 1987, Schilder 1988). Ein weiterer Aspekt dieser
Arbeit sollte sein, eine Möglichkeit zu finden, die Sozialstruktur auch auf der
Grundlage defensiver und soziopositiver Verhaltenselemente zu definieren.
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Reader, S. M., & Laland, K. N. (2009). Animal Innovation. Oxford: Oxford University Press.
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