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Van Dongen W.F.D.,University of Chile | Maldonado K.,University of Chile | Maldonado K.,Institute Filosofia Y Ciencias Of La Complejidad | Sabat P.,University of Chile | And 2 more authors.
Behavioral Ecology | Year: 2010

Animal personalities are interindividual behavioral differences that are consistent across time or contexts. Increasing research is revealing the adaptive significance of personalities, although the mechanisms driving this variation remain largely unknown. A possible source of variation in personality traits is interpopulational differences in the strength of selection acting upon them. The response to selection can be measured indirectly via the behavior's repeatability, as repeatability generally sets an upper limit to trait heritability. However, no information currently exists on geographic variation in personality repeatability. We therefore quantified repeatability in exploratory behavior, a common personality trait, over multiple trials for 3 populations of rufous-collared sparrow (Zonotrichia capensis), focusing on 3 specific measures (exploration speed, diversity of perches visited, and number of hops). We also asked how differences in repeatability of these 3 measures affect other aspects of exploration, such as the temporal consistency of intercorrelations between the measures. Exploration speed was highly repeatable across all populations, whereas diversity was only repeatable in 2 of 3 populations and hopping behavior not at all. These differences in repeatability lead to temporal variation in the correlation matrices of the 3 exploration measures. Finally, only trial number influenced interindividual variability in exploration, whereas population identity, experimental conditions (i.e., conducting the novel environment assay under laboratory or field conditions), and time since capture all had no effect. Our findings highlight the complexity of using measures of behavioral consistency as a definition of personalities and emphasize the value of quantifying interpopulational patterns of trait repeatability. © The Author 2010. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved. Source

Romero-Maltrana D.,Pontifical Catholic University of Valparaiso | Romero-Maltrana D.,Institute Filosofia Y Ciencias Of La Complejidad
Studies in History and Philosophy of Science Part B - Studies in History and Philosophy of Modern Physics | Year: 2015

There is general consensus among physicists in considering symmetries as a source of conserved quantities, a conclusion allegedly supported by Emmy Noether's theorems. Recently it has been pointed out that no arrow of explanation can be extracted from Noether's work, and there are also criticisms against the priority of particular symmetries over specific conserved quantities under Noether's ideas, but there are no general arguments against the aforementioned consensus, nor proposals promoting an explanation that leads from conserved quantities to symmetries. In this paper a general argument is built which favours conserved quantities over symmetries inasmuch as the presence of the former seems to allow (i.e. it seems to be a sufficient condition leading to) symmetrical descriptions. © 2015 Elsevier Ltd. Source

Maldonado K.,Institute Filosofia Y Ciencias Of La Complejidad | Bozinovic F.,University of La Serena | Rojas J.,University of Santiago de Chile | Sabat P.,University of Chile
Physiological and Biochemical Zoology | Year: 2011

The climatic variability hypothesis (CVH) states that species are geographically more widespread at higher latitudes because individuals have a broader range of physiological tolerance or phenotypic flexibility as latitude and climatic variability increase. However, it remains unclear to what extent climatic variability or latitude, acting on the phenotype, account for any observed geographical gradient in mean range size. In this study, we analyzed the physiological flexibility within the CVH framework by using an intraspecific population experimental approach. We tested for a positive relationship between digestive- tract flexibility (i.e., morphology and enzyme activities) and latitude and climatic and natural diet variability in populations of rufous-collared sparrows (Zonotrichia capensis) captured in desert (27°S), Mediterranean (33°S), and coldtemperate (41°S) sites in Chile. In accordance with the CVH, we observed a positive relationship between the magnitude of digestive-tract flexibility and environmental variability but not latitude. The greatest digestive flexibility was observed in birds at middle latitudes, which experience the most environmental variability (a Mediterranean climate), whereas individuals from the most stable climates (desert and cold-temperate) exhibited little or no digestive-tract flexibility in response to experimental diets. Our findings support the idea that latitudinal gradients in geographical ranges may be strongly affected by the action of regional features, which makes it difficult to find general patterns in the distribution of species.© 2011 by The University of Chicago. All rights reserved. Source

Gonzalez-Gomez P.L.,University of Chile | Gonzalez-Gomez P.L.,Institute Filosofia Y Ciencias Of La Complejidad | Bozinovic F.,University of Chile | Vasquez R.A.,University of Chile
Animal Behaviour | Year: 2011

Episodic memory has been described as the ability to recall personal past events, involving what, where and when an event has been experienced. Cognitive abilities like learning and memory are pivotal to the performance of many behavioural traits such as food procurement. Nectar, the primary food of hummingbirds, is dispersed in hundreds of flowers and varies in concentration and renewal rate. Therefore, a hummingbird that can remember elements of episodic-like memory such as what, where and when the nectar becomes available will have a higher energy rate of intake when compared to random foraging. We conducted a field experiment with green-backed firecrown hummingbirds, Sephanoides sephaniodes. We assessed the ability to recall the location, nectar quality and renewal rate of the most rewarding flowers among several less rewarding flowers with identical visual cues. Hummingbirds were able to remember the most profitable nectar sources and flower position and adjust their visits to nectar renewal interval. Cognitive performance varied among individuals, implying up to 6.3-fold differences in energy gain. Our results strongly suggest that hummingbirds use cognitive abilities to exploit nectar sources efficiently and, therefore, that cognitive abilities are potentially tied to survival probability. © 2011 The Association for the Study of Animal Behaviour. Source

Razeto-Barry P.,Institute Filosofia Y Ciencias Of La Complejidad | Razeto-Barry P.,Diego Portales University
Origins of Life and Evolution of Biospheres | Year: 2012

The concept of autopoiesis was proposed 40 years ago as a definition of a living being, with the aim of providing a unifying concept for biology. The concept has also been extended to the theory of knowledge and to different areas of the social and behavioral sciences. Given some ambiguities of the original definitions of autopoiesis, the concept has been criticized and has been interpreted in diverse and even contradictory ways, which has prevented its integration into the biological sciences where it originated. Here I present a critical review and conceptual analysis of the definition of autopoiesis, and propose a new definition that is more precise, clear, and concise than the original ones. I argue that the difficulty in understanding the term lies in its refined conceptual subtlety and not, as has been claimed by some authors, because it is a vacuous, trivial or very complex concept. I also relate the concept of autopoiesis to the concepts of closed systems, boundaries, homeostasis, self-reproduction, causal circularity, organization and multicellularity. I show that under my proposed definition the concept of a molecular autopoietic system is a good demarcation criterion of a living being, allowing its general integration into the biological sciences and enhancing its interdisciplinary use. © 2012 Springer Science+Business Media Dordrecht. Source

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