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Arcata, CA, United States

Humboldt State University is the northernmost campus of the California State University system, located in Arcata within Humboldt County, California, USA. The main campus, nestled at the edge of a coast redwood forest, has commanding views of Humboldt Bay and the Pacific Ocean. Its location eight miles north of Eureka and 279 miles north of San Francisco on the North Coast of California is notable for its natural beauty and relative remoteness. Wikipedia.

Railsback S.F.,Humboldt State University | Harvey B.C.,Pacific Southwest Research Station
Trends in Ecology and Evolution | Year: 2013

Many ecologists believe that there is a lack of foraging theory that works in community contexts, for populations of unique individuals each making trade-offs between food and risk that are subject to feedbacks from behavior of others. Such theory is necessary to reproduce the trait-mediated trophic interactions now recognized as widespread and strong. Game theory can address feedbacks but does not provide foraging theory for unique individuals in variable environments. 'State- and prediction-based theory' (SPT) is a new approach that combines existing trade-off methods with routine updating: individuals regularly predict future food availability and risk from current conditions to optimize a fitness measure. SPT can reproduce a variety of realistic foraging behaviors and trait-mediated trophic interactions with feedbacks, even when the environment is unpredictable. © 2012 Elsevier Ltd. Source

The variance in relative fitness, commonly called the "opportunity for selection," is a measure of the maximum amount of selection that can occur in a population. I review the relation between fitness variance and population growth, showing that fitness variance is higher during periods of population decline. This is true both for survival and for commonly used models for variable descendant number (Poisson, negative binomial, generalized Poisson). Empirical evidence suggests that not just the opportunity for selection but also the actual selection occurring is commonly greater during such periods of population reduction. © 2012 Springer Science+Business Media Dordrecht. Source

Swartz R.,Humboldt State University
Harm Reduction Journal | Year: 2010

Background: The rise of authorized marijuana use in the U.S. means that many individuals are using cannabis as they concurrently engage in other forms of treatment, such as substance abuse counseling and psychotherapy. Clinical and legal decisions may be influenced by findings that suggest marijuana use during treatment serves as an obstacle to treatment success, compromises treatment integrity, or increases the prevalence or severity of relapse. In this paper, the author reviews the relationship between authorized marijuana use and substance abuse treatment utilizing data from a preliminary pilot study that, for the first time, uses a systematic methodology to collect data examining possible effects on treatment.Methods: Data from the California Outcomes Measurement System (CalOMS) were compared for medical (authorized) marijuana users and non-marijuana users who were admitted to a public substance abuse treatment program in California. Behavioral and social treatment outcomes recorded by clinical staff at discharge and reported to the California Department of Alcohol and Drug Programs were assessed for both groups, which included a sample of 18 reported medical marijuana users.Results: While the findings described here are preliminary and very limited due to the small sample size, the study demonstrates that questions about the relationship between medical marijuana use and involvement in drug treatment can be systematically evaluated. In this small sample, cannabis use did not seem to compromise substance abuse treatment amongst the medical marijuana using group, who (based on these preliminary data) fared equal to or better than non-medical marijuana users in several important outcome categories (e.g., treatment completion, criminal justice involvement, medical concerns).Conclusions: This exploratory study suggests that medical marijuana is consistent with participation in other forms of drug treatment and may not adversely affect positive treatment outcomes. These findings call for more extensive sampling in future research to allow for more rigorous research on the growing population of medical marijuana users and non-marijuana users who are engaged in substance abuse treatment. © 2010 Swartz; licensee BioMed Central Ltd. Source

Grimm V.,Helmholtz Center for Environmental Research | Railsback S.F.,Humboldt State University
Philosophical Transactions of the Royal Society B: Biological Sciences | Year: 2012

Modern ecology recognizes that modelling systems across scales and at multiple levels-especially to link population and ecosystem dynamics to individual adaptive behaviour-is essential for making the science predictive. 'Pattern-oriented modelling' (POM) is a strategy for doing just this. POM is the multi-criteria design, selection and calibration of models of complex systems. POM starts with identifying a set of patterns observed at multiple scales and levels that characterize a system with respect to the particular problem being modelled; a model from which the patterns emerge should contain the right mechanisms to address the problem. These patterns are then used to (i) determine what scales, entities, variables and processes the model needs, (ii) test and select submodels to represent key low-level processes such as adaptive behaviour, and (iii) find useful parameter values during calibration. Patterns are already often used in these ways, but a mini-review of applications of POM confirms that making the selection and use of patterns more explicit and rigorous can facilitate the development of models with the right level of complexity to understand ecological systems and predict their response to novel conditions. © 2011 The Royal Society. Source

The ichnogenus Melatercichnus was described in 1991 from Cretaceous deep-ocean turbidte beds at Trinidad Bay, northern California. The type (and only) ichnospecies, Melatercichnus burkei, features all the primary characters (ichnotaxobases) of Phymatoderma, and is here reassigned to this ichnogenus. In so doing, Phymatoderma now consists of two palmate forms (P. penicillum and P. alcicorne), two digitate forms (P. melvillensis and P. granulata), and the reassigned ichnospecies (P. burkei) representing a kind of intermediate form. Reassignment follows the doctrine of ichnotaxonomic conservatism, by employing a limited number of primary characters and abandoning a superfluous ichnotaxon. All of the ichnospecies now included within Phymatoderma-as seems to be true of many of the so-called fucoids and certain other groups of trace fossils-are extremely variable in terms of morphology, although basic structure (in this case bunches of outward branching, unlined tunnels stuffed with fecal pellets) is consistent. This aspect of trace fossils needs more attention, both from an ichnotaxonomic and a biologic point of view. At the Trinidad Bay collecting site, the 'perfect' examples of P. burkei featuring all the characters of the ichnospecies grade into specimens that would be identified with P. granulata or possibly Alcyonidiopsis isp. if preserved in isolation or if the 'perfect' specimens had never been observed. These variants are difficult to accommodate in traditional ichnotaxonomy, pointing to a need for special categories in open nomenclature (e.g., identification of some of the 'imperfect' specimens as '. Phymatoderma forma variabilis' or possibly '. Phymatoderma f. v. P. burkei-P. granulata'-to reflect the kind and degree of variation). In terms of behavioral ecology, P. burkei appears to be a fancy cesspit: the producer either fed at a different level and simultaneously deposited fecal pellets at depth (polychaete, echiuran?), or fed at or near the seafloor then dove into the turbidite sand blanket to discharge the pellets (sipunculan?). Variations in the structure could have resulted from the producer encountering different conditions in the substrate at different times and places (e.g., owing to dewatering), interruptions in the typical pattern caused by encounters with other organisms, limited time available to construct the usual pellet-filled structure, avoidance of other conspecific burrowers, or simply the inability of some individuals to execute precisely the construction plan. © 2011 Elsevier B.V. Source

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