A comprehensive study of personal and social information use in female brown-headed cowbirds, Molothrus ater

Brood parasites face considerable cognitive challenges when locating and selecting host nests for their young. One aspect of this challenge is determining how to use different sources of information to make decisions regarding the quality of a prospective nest. Here we investigate how female-brown-headed cowbirds, Molothrus ater, use information when prospecting for nests, and then expand upon this to investigate decisions related to foraging. In chapter 1, we demonstrated female could use social information acquired from observing the nest prospecting patterns of conspecifics to influence their own patterns of nest selection. Furthermore, we found a negative relationship between a female’s accuracy at using personal information and her tendency to copy others. In chapter 2, we found the females were able to use social information in a foraging setting as well. The female’s accuracy using personal information remained consistent across nest prospecting and foraging contexts however, the relationship between accuracy and tendency to copy others drastically reversed. A follow up experiment revealed the likely possibility that the differing relationship between personal and social information use depended on the degree of conflict that existed between the two types of information. In chapter 3, we redeveloped and implemented a new RFID tracking technology allowing us to investigate how the cognitive strategies from chapters 1 and 2 translated to a naturalistic, socially complex breeding environment. We found female cowbirds who spent more time prospecting, produced a greater quantity of eggs and demonstrated high accuracy scores during chapter 1 and 2, whereas females who relied on copying others spent significantly less time prospecting and demonstrated lower laying accuracy scores. By demonstrating how individuals’ cognitive strategies relate across context and translate to a socially complex setting, we have demonstrated the importance of examining behaviour in both of these settings and our RFID tracking technology provides researchers with the framework to effectively study this in the future

Historijska pripovjednost i problem istine u historijskom prikazivanju

Je li prošlost priča? Oko tog kratkog i, na prvi pogled, suvišnoga pitanja vrti se ne samo esej koji je pred nama, već i čitava postmodernistička rasprava o povijesti. U jedno nema sumnje: prošlost predstavljamo kao priču i prošlost rekonstruiramo (uglavnom) na osnovu priča. Ovime smo ukratko opisali povijest kao istraživačku (znanstvenu) djelatnost i jasno predočili njenu povezanost s pričom odnosno pripovijedanjem. Upravo zbog te jasne veze povijesti s pričom, ono pitanje s kojim smo započeli uvod čini nam se suvišnim. Ali povijest ( shvaćena u smislu koji smo prije spomenuli) nije prošlost; ona tek opisuje, prepričava prošle događaje. Jedan od prvih povjesničara koji su počeli ukazivati na spomenutu problematiku bio je Hayden White, američki filozof i povjesničar rođen 1928. godine. Njegova knjiga Metahistory: The Historical Imagination in Nineteenth Century Europe iz 1973. godine predstavljala je pionirski rad u uvođenju problema poznatog kao “lingvistički zaokret” u predmet historiografije. Stavljajući povijesnu znanost kao predmet te iste znanosti on ju ustvari razotkriva kao poetičku djelatnost, čime je pokrenuo raspravu koja do danas nije prestala. U eseju koji je ovdje predstavljen, White na primjeru prikazivanja Holokausta pokazuje presudan utjecaj načina pripovjedanja u prikazivanju prošlosti. Nudi li nam se Holokaust, kao prošli događaj nesumnjive strave i nesreće, sam po sebi kao tragedija, ili ga se može prikazati u nekom dugom pripovjednome modusu? Ako pak tragedija nije jedini mogući način prikazivanja Holokausta, znači li to da narav događaja ne određuje vrstu priče koju možemo uporabiti u njegovu prikazivanju? A što tek reći o stavu na koji se White osobito osvrće u eseju po kojemu Holokaust predstavlja događaj kojeg u potpunosti ne može ispričati nikakav ljudski jezik. Ako je tomu tako, zaključak je jasan: prošlost nije priča. Prošlost dakle nije priča, dok povijest to jest; na taj način kida se veza povjesničarske djelatnosti i njenog predmeta- prošlih zbivanja, veza koju povjesničar u pravilu uzima kao samu po sebi razumljivom

Man-made Fibres? The Split Personalities of Victorian Manliness

This essay investigates the textual traces of a split that was central to the Victorian conception of manliness: the contradiction of gentlemanliness which demanded both the capacity to commit violence and the requirement to be ‘civilized’. It suggests that there is a fault line running through the fabric of masculinity which can be seen in the texts which train boys to become men, which remember and reconstruct that training and which consider manliness in its mature forms. A man is a subject who acts; he is also subjected to forces which he does not control. In fiction, long and short, and in poetry, masculinity is repeatedly shown to be both contested and constructed – a man-made fibre, not a natural or god-given status. From Tennyson to Wilde, there is a tear in the cloth. Keywords: Victorian manliness and masculinity; gentlemanliness; Alfred Tennyson; Charles Dickens; Rudyard Kipling; Saki (H. H. Munro); Oscar Wilde; Robert Louis Stevenson

Hole-Pairs in a Spin Liquid: Influence of Electrostatic Hole-Hole Repulsion

The stability of hole bound states in the t-J model including short-range Coulomb interactions is analyzed using computational techniques on ladders with up to $2 \times 30$ sites. For a nearest-neighbors (NN) hole-hole repulsion, the two-holes bound state is surprisingly robust and breaks only when the repulsion is several times the exchange $J$. At $\sim 10$ hole doping the pairs break only for a NN-repulsion as large as $V \sim 4J$. Pair-pair correlations remain robust in the regime of hole binding. The results support electronic hole-pairing mechanisms on ladders based on holes moving in spin-liquid backgrounds. Implications in two dimensions are also presented. The need for better estimations of the range and strength of the Coulomb interaction in copper-oxides is remarked.Comment: Revised version with new figures. 4 pages, 5 figure

Non-Fermi liquid regime of a doped Mott insulator

We study the doping of a Mott insulator in the presence of quenched frustrating disorder in the magnetic exchange. A low doping regime $\delta<J/t$ is found, in which the quasiparticle coherent scale is low : $\epsilon_F^* = J (\delta/\delta^*)^2$ with $\delta^*=J/t$ (the ratio of typical exchange to hopping). In the ``quantum critical regime'' $\epsilon_F^*<T<J$, several physical quantities display Marginal Fermi Liquid behaviour : NMR relaxation time $1/T_1\sim const.$, resistivity $\rho_{dc}(T) \propto T$, optical lifetime \tau_{opt}^{-1}\propto \omega/\ln(\omega/\epstar) and response functions obey $\omega/T$ scaling, e.g. $J\sum_q \chi''(q,\omega) \propto \tanh (\omega/2T)$. In contrast, single-electron properties display stronger deviations from Fermi liquid theory in this regime with a $\sqrt{\omega}$ dependence of the inverse single-particle lifetime and a $1/\sqrt{\omega}$ decay of the photoemission intensity. On the basis of this model and of various experimental evidence, it is argued that the proximity of a quantum critical point separating a glassy Mott-Anderson insulator from a metallic ground-state is an important ingredient in the physics of the normal state of cuprate superconductors (particularly the Zn-doped materials). In this picture the corresponding quantum critical regime is a ``slushy'' state of spins and holes with slow spin and charge dynamics responsible for the anomalous properties of the normal state.Comment: 40 pages, RevTeX, including 13 figures in EPS. v2 : minor changes, some references adde

Figural realism: studies in the mimesis effect

Publicado originalmente en 1998. En sus libros anteriores, como Trópicos del discurso y El contenido de la forma, Hayden White se centró en las convenciones de la escritura histórica y en la ordenación de la conciencia histórica. En Figural Realism, White recoge ocho ensayos interrelacionados que se ocupan principalmente del tratamiento de la historia en el discurso crítico literario reciente. "La 'historia' no es sólo un objeto que podemos estudiar", escribe White, "es también, e incluso principalmente, un cierto tipo de relación con 'el pasado' mediada por un tipo distintivo de discurso escrito". Es porque el discurso histórico se actualiza en su forma culturalmente significativa como un tipo específico de escritura que podemos considerar la relevancia de la teoría literaria tanto para la teoría como para la práctica de la historiografía."post-print205 p

On the research and the writing phase of the historian's work

This comment on Chris Lorenz’s comment on my work indicates a number of typical failings of reviewers, of which Lorenz’s comments on my talk are typical. One, like most philosophers, Lorenz treats my work as a whole rather than as a congeries of individual works as if they were all written and published at the same time. He finds inconsistencies or contradictions between works written many years apart. My response is that many of these inconsistencies are a result of changes in my point of view over time. Secondly, instead of quoting a passage from my work and criticising it, Lorenz typically paraphrases an argument and then proceeds to criticise his own paraphrase. Often, I do not recognise the paraphrase as a position I hold. Third, I hold that historical writing is often and should be more associative than logical, more poetic than technical. Fourth, about causality in history, I do not think that we have any examples of a universal causal law of historical change or structure. So his demand for a causal law from me is beside the point

Less is more: Burkholderia pseudomallei and chronic melioidosis

10.1128/mBio.00709-13mBio45