Visual attention mechanisms are known to select information to process based on current goals, personal relevance, and lowerlevel features. Here we present evidence that human visual attention also includes a high-level category-specialized system that monitors animals in an ongoing manner. Exposed to alternations between complex natural scenes and duplicates with a single change (a change-detection paradigm), subjects are substantially faster and more accurate at detecting changes in animals relative to changes in all tested categories of inanimate objects, even vehicles, which they have been trained for years to monitor for sudden life-or-death changes in trajectory. This animate monitoring bias could not be accounted for by differences in lower-level visual characteristics, how interesting the target objects were, experience, or expertise, implicating mechanisms that evolved to direct attention differentially to objects by virtue of their membership in ancestrally important categories, regardless of their current utility.animacy ͉ category specificity ͉ domain specificity ͉ evolutionary psychology ͉ visual attention V isual attention is an umbrella term for the set of operations that select some portions of a scene, rather than others, for more extensive processing. These operations evolved because some categories of information in the visual environment were likely to be more important or time-sensitive than others for activities that contributed to an organism's survival or reproduction. The selection criteria that direct visual attention can be categorized by their origin: (i) goal-derived: criteria activated volitionally in response to a transient internally represented goal; (ii) ancestrally derived: criteria so generally useful for a species, generation after generation, that natural selection favored mechanisms that cause them to develop in a species-typical manner; and (iii) expertise-derived: criteria extracted during ontogeny by evolved mechanisms specialized for detecting which perceptual cues predict information that enhances task performance.These three types of criteria may also interact; for example, differential experience or temporary goals could calibrate or elaborate ancestrally derived criteria built into the attentional architecture.The ways in which human attention can be affected by goals and expertise have been extensively investigated. Indeed, humans are zoologically unique in the extent to which we evolved to engage in behavior tailored to achieve situation-specific goals as a regular part of our subsistence and sociality (1, 2). Among our foraging ancestors, improvising solutions in response to the distinctive features of situations would have benefited from the existence of goal-driven voluntary attentional mechanisms. As predicted by such a view, otherwise arbitrary but task-relevant objects command more attention than task-irrelevant ones (3), and expertise in a task domain shifts attention to more tasksignificant objects (4), features (5), and locations (6).In contrast, attentio...

We present evidence for an evolved sexually dimorphic adaptation that activates spatial memory and navigation skills in response to fruits, vegetables and other traditionally gatherable sessile food resources. In spite of extensive evidence for a male advantage on a wide variety of navigational tasks, we demonstrate that a simple but ecologically important shift in content can reverse this sex difference. This effect is predicted by and consistent with the theory that a sexual division in ancestral foraging labour selected for gathering-specific spatial mechanisms, some of which are sexually differentiated. The hypothesis that gathering-specific spatial adaptations exist in the human mind is further supported by our finding that spatial memory is preferentially engaged for resources with higher nutritional quality (e.g. caloric density). This result strongly suggests that the underlying mechanisms evolved in part as adaptations for efficient foraging. Together, these results demonstrate that human spatial cognition is content sensitive, domain specific and designed by natural selection to mesh with important regularities of the ancestral world.

Time can appear to slow down in certain brief real-life events-e.g. during car accidents or critical moments of athletes' performances. Such time dilation can also be produced to a smaller degree in the laboratory by 'oddballs' presented in series of otherwise identical stimuli. We explored the spatial distribution of subjective time dilation: Does time expand only for the oddball objects themselves, only for the local spatial region including the oddball, or for the entire visual field? Because real-life traumatic events provoke an apparently global visual experience of time expansion, we predicted-and observed-that a locally discrete oddball would also dilate the apparent duration of other concurrent events in other parts of the visual field. This 'dilation at a distance' was not diminished by increasing spatial separation between the oddball and target events, and was not influenced by manipulations of objecthood that drive object-based attention. In addition, behaviorally 'urgent' oddballs (looming objects) yielded time dilation, but visually similar receding objects did not. We interpret these results in terms of the influence of attention on time perception-where attention reflects general arousal and faster internal pacing rather than spatial or object-based selection, per se. As a result, attention influences subjective time dilation as a global visual experience.

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