101 research outputs found

    Using playback of territorial calls to investigate mechanisms of kin discrimination in red squirrels

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    Kin recognition can facilitate kin selection and may have played a role in the evolution of sociality. Red squirrels (Tamiasciurus hudsonicus) defend territories using vocalizations known as rattles. They use rattles to discriminate kin, though the mechanism underlying this ability is unknown. Our objective was to distinguish between the mechanisms of prior association, where animals learn the phenotypes of kin they associate with early in life, and phenotype matching/recognition alleles, where animals use a template to match phenotypes, thereby allowing them to recognize kin without an association early in life. We used audio playbacks to measure the responses of squirrels to rattles from familiar kin, unfamiliar kin, and non-kin. Initial analyses revealed that red squirrels did not discriminate between familiar and unfamiliar kin, but also did not discriminate between kin and non-kin, despite previous evidence indicating this capability. Post hoc analyses showed that a squirrel’s propensity to rattle in response to playback depended on an interaction between relatedness and how the playback stimuli had been recorded. Red squirrels discriminated between rattles from close kin (r = 0.5) and rattles from non-kin (r < 0.125) when the rattles were recorded from provoked squirrels. Squirrels did not exhibit kin discrimination in response to unsolicited rattles. Once we accounted for how the stimuli had been recorded, we found no difference in the responses to familiar and unfamiliar kin. Our study suggests that kin discrimination by red squirrels may be context dependent

    Red squirrels use territorial vocalizations for kin discrimination

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    The ability to discriminate among individuals, or among classes of individuals, can provide animals with important fitness benefits. Although several mechanisms for discrimination are possible, most require animals to show stable phenotypic variation that reflects their identity or their membership in a particular class (e.g. sex, mate, kin). For territorial animals that rarely interact physically, vocalizations could serve as long-distance signals that facilitate discrimination. In this study, we tested whether the territorial rattle vocalizations of North American red squirrels, Tamiasciurus hudsonicus, are repeatable, and whether they could hence provide the basis for multiple types of discrimination. We measured four structural features from two rattles from each of 76 marked squirrels. All four features were repeatable, which is consistent with territorial rattles being individually distinctive. We then conducted a playback experiment to determine whether squirrels use rattles for discrimination. Specifically, we tested whether squirrels discriminate between the rattles of neighbours and non-neighbours, and kin (coefficient of relatedness, r ≥ 0.25) and non-kin (r < 0.125). Following a 2 × 2 factorial design, we broadcast a rattle from a non-neighbouring nonkin individual to 15 subjects, from a neighbouring nonkin individual to 14 subjects, from a non-neighbouring kin individual to 11 subjects, and from a neighbouring kin individual to 13 subjects. Subjects did not discriminate between the rattles of neighbours and non-neighbours, but did respond differently to the rattles of kin and nonkin. Specifically, squirrels were significantly more likely to produce a rattle of their own in response to the broadcasted rattles of nonkin versus the broadcasted rattles of kin. This result demonstrates that red squirrels can use territorial vocalizations for kin discrimination. It also suggests that they are more tolerant of territorial intrusions by kin

    The two forms of capitalism: developmentalism and economic liberalism

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    ABSTRACT This paper argues that the state and the market are the main institutions regulating capitalism, and, correspondingly, that the form of the economic and political coordination of capitalism will be either developmental or liberal. It defines the developmental state, relates it to the formation of a developmental class coalition, and notes that capitalism was born developmental in its mercantilist phase, turned liberal in the nineteenth century, and, after 1929, became once again developmental, but, now, democratic and progressive. All industrial and capitalist revolutions took place within the framework of developmentalism, whereby the state coordinates the non-competitive sector of the economy and the five macroeconomic prices (which the market is unable to make “right”), while the market coordinates the competitive sector. In the 1970s, a crisis opened the way for a short-lived and reactionary form of capitalism, neoliberalism or rentier-financier capitalism. Since the 2008 Global Financial Crisis, the neoliberal hegemony has come to an end, and we are now experiencing a period of transition.</div

    Financial Systems and Industrial Policy in Germany and Great Britain: The Limits of Convergence

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    E Pluribus Unum? Varieties and Commonalities of Capitalism

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    The Global Financial Crisis and a New Capitalism?

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    The 2008 global financial crisis was the consequence of the process (1) of financialization, or the creation of massive fictitious financial wealth, that began in the 1980s,; and (2) the hegemony of a reactionary ideology-namely, neoliberalism-based on self-regulated and efficient markets. Although laissez-faire capitalism is intrinsically unstable, the lessons of the 1929 stock market crash of 1929 and the Great Depression of the 1930s were transformed into theories and institutions or regulations that led to the '30 glorious years of capitalism' (1948-77) and that could have helped avoid a financial crisis as profound as the present one. But it did not, because a coalition of rentiers and 'financists' achieved hegemony and, while deregulating the existing financial operations, refused to regulate the financial innovations that made these markets even riskier. Neoclassical economics played the role of a meta-ideology as it legitimized, mathematically and 'scientifically,' neoliberal ideology and deregulation. From this crisis a new democratic capitalist system will emerge, though its character is difficult to predict. It will not be financialized, but the glory years' tendencies toward a global and knowledge-based capitalism in which professionals have more say than rentier capitalists, as well as the tendency to improve democracy by making it more social and participative, will be resumed
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