Pseudoreplication is one of the most influential methodological issues in ecological and animal behavior research today. At its inception, the idea of pseudoreplication highlighted important concerns about the design and analysis of experiments in ecology. The doctrine purported to provide a unified view of experimental design and analysis, wherein precise criteria could be used to assess manuscripts and research proposals for acceptance or rejection. Few methodological doctrines have had as much impact as pseudoreplication, yet there has been very little critical analysis of it. In this paper, the authors extend the growing criticism of the concept of pseudoreplication. The authors argue that the core ideas behind pseudoreplication are based on a misunderstanding of statistical independence, the nature of control groups in science, and contexts of statistical inference. The authors also highlight how other areas of research have found and responded to similar issues in the design and analysis of experiments through the use of more advanced statistical methods. Ultimately, there are no universal criteria for accepting or rejecting experimental research; all research must be judged on its own merits.

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It has long been proposed that cooperation should increase in harsh environments, but this claim still lacks theoretical underpinnings. We modeled a scenario in which benefiting from altruistic behavior was essential to survival and reproduction. We used a spatial agent-based model to represent mutual cooperation enforced by environmental adversity. We studied two factors, the cost of unreciprocated cooperation and the environmental cost of living, which highlight a conflict between the short- and long-term rewards of cooperation. In the long run, cooperation is favored because only groups with a sufficient number of cooperators will survive. In the short run, however, harsh environmental costs increase the advantage of defectors in cooperator-defector interactions because the loss of resources leads to death. Our analysis sheds new light on the evolution of cooperation via interdependence and illustrates how selfish groups can incur short-term benefits at the cost of their eventual demise. We demonstrate how harsh environments select for cooperative phenotypes and suggest an explanation for the adoption of cooperative breeding strategies in human evolution. We also highlight the importance of variable population size and the role of socio-spatial organization in harsh environments.

Since M. K. McClintock (1971) published the 1st study on menstrual synchrony among women, a number of other studies have also reported synchrony using a variety of methods. The most recent reports of synchrony come from A. Weller, L. Weller, and colleagues, and their findings of synchrony have been getting stronger (by their own account). In this article, the author analyzes their new methodology and presents 2 simulation studies that demonstrate how biases and errors can produce synchrony as an artifact. Two mutually reinforcing categories of errors are identified: (a) errors in calculating the expected mean onset difference between cycles when there is cycle variability and (b) errors that may result from allowing participants to fill out menstrual-cycle-onset calendars, including recall biases and the mutual exchange of information. It is suggested that synchrony may be a biological state to be avoided and that cycle variability may facilitate female mate choice.

Wild bonnet macaques (Macaca radiata) were studied in southern India to assess their ability to discriminate non-venomous, venomous and predatory snakes. Realistic snake models were presented to eight troops of bonnet macaques at feeding stations and their behavior was video-recorded 3 min before and 3 min after snake exposure. Snakes presented were: (1) venomous Indian cobra (Naja naja) displaying an open hood with ÔeyespotsÕ; (2) venomous common Indian krait (Bungarus caeruleus); (3) non-venomous green keelback (Macropisthodan plumbicolor); (4) non-venomous rat snake (Ptyas mucosus); and (5) Indian python (Python molurus) which preys on macaques. Latencies to detect and react to the snakes were evaluated to determine initial responsiveness. Longer-term assessment was measured as the percentage of time individuals looked at the snakes and monitored the activity of nearby individuals before and after snake detection. All snake models engendered caution and maintenance of a safe distance. Alarm calling occurred only during python presentations. The cobra engendered a startle response or running in the largest percentage of individuals after its detection, whereas the rat snake and python elicited bipedal standing or ambulating to monitor the snakes. We also examined the influence of age on snake recognition. Juveniles and subadults looked at the cobra, krait, and python for a larger percentage of time than adults did; albeit, adults looked at the python substantially longer than at the other snakes. Age differences in behavior suggest that, with the exception of the python, repeated experience with snakes in the wild moderates excitability, consistent with the likely threat of envenomation.