Eco-evolutionary feedbacks in community and ecosystem ecology: interactions between the ecological theatre and the evolutionary play.

Interactions between natural selection and environmental change are well recognized and sit at the core of ecology and evolutionary biology. Reciprocal interactions between ecology and evolution, eco-evolutionary feedbacks, are less well studied, even though they may be critical for understanding the evolution of biological diversity, the structure of communities and the function of ecosystems. Eco-evolutionary feedbacks require that populations alter their environment (niche construction) and that those changes in the environment feed back to influence the subsequent evolution of the population. There is strong evidence that organisms influence their environment through predation, nutrient excretion and habitat modification, and that populations evolve in response to changes in their environment at time-scales congruent with ecological change (contemporary evolution). Here, we outline how the niche construction and contemporary evolution interact to alter the direction of evolution and the structure and function of communities and ecosystems. We then present five empirical systems that highlight important characteristics of eco-evolutionary feedbacks: rotifer-algae chemostats; alewife-zooplankton interactions in lakes; guppy life-history evolution and nutrient cycling in streams; avian seed predators and plants; and tree leaf chemistry and soil processes. The alewife-zooplankton system provides the most complete evidence for eco-evolutionary feedbacks, but other systems highlight the potential for eco-evolutionary feedbacks in a wide variety of natural systems.

The Role of Social Cognition and Person Perception in Economic Social Decision-Making

Social decision-making is often complex, requiring the decision-maker to make social inferences about another person in addition to engaging traditional decision-making processes. However, until recently, much research in neuroeconomics and behavioral economics has examined social decision-making while failing to take into account the importance of the social context and social cognitive processes that are engaged when viewing another person. Using social psychological theory to guide our hypotheses, four research studies investigate the role of social cognition and person perception in guiding economic decisions made in social contexts. The first study (Chapter 2) demonstrates that only specific types of social information engage brain regions implicated in social cognition and hinder learning in social contexts. Study 2 (Chapter 3) extends these findings and examines contexts in which this social information is used to generalize across contexts to form predictions about another person’s behavior. Study 3 (Chapter 4) demonstrates that under certain contexts these social cognitive processes may be withheld in order to more effectively complete the task at hand. Last, Study 4 (Chapter 5) examines how this knowledge of social cognitive processing can be used to change behavior in a prosocial group context. Taken together, these studies add to the growing body of literature examining decision-making in social contexts and highlight the importance of social cognitive processing in guiding these decisions. Although social cognitive processing typically facilitates social interactions, these processes may alter economic decision-making in social contexts.

Contrary Voices: Heine, Holderlin, and Goethe in the music of Hanns Eisler

Contrary Voices examines composer Hanns Eisler’s settings of nineteenth-century poetry under changing political pressures from 1925 to 1962. The poets’ ideologically fraught reception histories, both under Nazism and in East Germany, led Eisler to intervene in this reception and voice dissent by radically fragmenting the texts. His musical settings both absorb and disturb the charisma of nineteenth-century sound materials, through formal parody, dissonance, and interruption. Eisler’s montage-like work foregrounds the difficult position of a modernist artist speaking both to and against political demands placed on art. Often the very charisma the composer seeks to expose for its power to sway the body politic exerts a force of its own. At the same time, his text-settings resist ideological rigidity in their polyphonic play. A dialogic approach to musical adaptation shows that, as Eisler seeks to resignify Heine’s problematic status in the Weimar Republic, Hölderlin’s appropriation under Nazism, and Goethe’s status as a nationalist symbol in the nascent German Democratic Republic, his music invests these poetic voices with surprising fragility and multivalence. It also destabilizes received gender tropes, in the masculine vulnerability of Eisler’s Heine choruses from 1925 and in the androgynous voices of his 1940s Hölderlin exile songs and later Goethe settings. Cross-reading the texts after hearing such musical treatment illuminates faultlines and complexities less obvious in text-only analysis. Ultimately Eisler’s music translates canonical material into a form as paradoxically faithful as it is violently fragmented.