Publications by authors named "Heidi Harley"

In this theme issue, our multidisciplinary contributors highlight the cognitive adaptations of marine mammals. The cognitive processes of this group are highly informative regarding how animals cope with specifics of and changes in the environment, because, not only did modern marine mammals evolve from numerous, non-related terrestrial animals to adapt to an aquatic lifestyle, but some of these species regularly move between two worlds, land and sea. Here, we bring together scientists from different fields and take the reader on a journey that begins with the ways in which modern marine mammals (whales, dolphins, seals, sea lions and manatees) utilize their perceptual systems, next moves into studies of the constraints and power of individuals' cognitive flexibility, and finally showcases how those systems are deployed in social and communicative contexts.

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As long-term studies reveal, bottlenose dolphin communities comprise a complex network of individual relationships. Individuals form strong bonds (e.g.

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Dolphins gain information through echolocation, a publicly accessible sensory system in which dolphins produce clicks and process returning echoes, thereby both investigating and contributing to auditory scenes. How their knowledge of these scenes contributes to their echoic information-seeking is unclear. Here, we investigate their top-down cognitive processes in an echoic matching-to-sample task in which targets and auditory scenes vary in their decipherability and shift from being completely unfamiliar to familiar.

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Macphail's comparative approach to intelligence focused on associative processes, an orientation inconsistent with more multifaceted lay and scientific understandings of the term. His ultimate emphasis on associative processes indicated few differences in intelligence among vertebrates. We explore options more attuned to common definitions by considering intelligence in terms of richness of representations of the world, the interconnectivity of those representations, the ability to flexibly change those connections, and knowledge.

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Aquatic species such as bottlenose dolphins can move in 3 dimensions and frequently view objects from different orientations. This study examined their ability to identify 2-D objects visually despite changes in orientation across 2 rotation planes. A dolphin performed a matching-to-sample task in which a sample was presented at a different orientation from its match in a 3-alternative choice array.

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Animal acoustic communication often takes the form of complex sequences, made up of multiple distinct acoustic units. Apart from the well-known example of birdsong, other animals such as insects, amphibians, and mammals (including bats, rodents, primates, and cetaceans) also generate complex acoustic sequences. Occasionally, such as with birdsong, the adaptive role of these sequences seems clear (e.

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Consciousness in dolphins? A review of recent evidence.

J Comp Physiol A Neuroethol Sens Neural Behav Physiol

June 2013

For millennia, dolphins have intrigued humans. Scientific study has confirmed that bottlenose dolphins are large-brained, highly social mammals with an extended developmental period, flexible cognitive capacities, and powerful acoustic abilities including a sophisticated echolocation system. These findings have led some to ask if dolphins experience aspects of consciousness.

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While the search for the neural basis of the language of thought is a laudable enterprise, and the article by Hurford a valiant first attempt, we argue that in investigating the argument structure of natural language it will ultimately prove more fruitful to consider the restrictions forced on the system by its inherently syntactic character.

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Bloom masterfully captures the state-of-the-art in the study of lexical acquisition. He also exposes the extent of our ignorance about the learning of names for non-observables. HCLMW adopts an innatist position without adopting modularity of mind; however, it seems likely that modularity is needed to bridge the gap between object names and the rest of the lexicon.

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Dolphin whistles vary by frequency contour, changes in frequency over time. Individual dolphins may broadcast their identities via uniquely contoured whistles, "signature whistles." A recent debate concerning categorization of these whistles has highlighted the on-going need for perceptual studies of whistles by dolphins.

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Echolocating bottlenose dolphins (Tursiops truncatus) discriminate between objects on the basis of the echoes reflected by the objects. However, it is not clear which echo features are important for object discrimination. To gain insight into the salient features, the authors had a dolphin perform a match-to-sample task and then presented human listeners with echoes from the same objects used in the dolphin's task.

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The focus of this study was to investigate how dolphins use acoustic features in returning echolocation signals to discriminate among objects. An echolocating dolphin performed a match-to-sample task with objects that varied in size, shape, material, and texture. After the task was completed, the features of the object echoes were measured (e.

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Despite the variety of verb meanings, linguistic research on their syntax and semantics has shown that they can be categorized into a finite and surprisingly small number of event types. More recently, research in the psycholinguistics of language acquisition and processing has emphasized the relevance of event type. The wider implication of these findings is that the conceptual fluidity of verbal concepts is confined by the fundamental structures of mental grammar, shedding light on this important interface between cognition and syntactic organization.

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How organisms (including people) recognize distant objects is a fundamental question. The correspondence between object characteristics (distal stimuli), like visual shape, and sensory characteristics (proximal stimuli), like retinal projection, is ambiguous. The view that sensory systems are 'designed' to 'pick up' ecologically useful information is vague about how such mechanisms might work.

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