High-resolution Niche Models via a Correlative Approach: Comparing and Combining Correlative and Process-based Information

Correlative and process-based approaches to describing the ecological niche in a spatially explicit fashion have often been compared in an adversarial framework. We sought to compare niche models developed via classic (correlative only), niche (process-based information), and hybridized (correlative augmented with process-based derived information) approaches, with the goal of determining if the added effort of process-based model development yielded better model fit. Correlative data layers (i.e., habitat models) included vegetation community types, Euclidean distance statistics, neighborhood analyses, and topographically-derived information. Mechanistic data layers were estimates of thermal suitability derived from field-collected datasets and biophysical calculations, and estimates of prey biomass interpolated from monitoring stations. We applied these models at high resolution (1 m × 1 m pixel size) to habitat occupied by a population of Texas horned lizards (Phrynosoma cornutum) located in central Oklahoma. Results suggested that our treatment of process-based information offered dramatically better identification of suitable habitat when compared to correlative information, but that these results were likely due to low variability of niche variable pixel values. Niche layers nearly perfectly predicted lizard locations; the interpretation of these results suggest that lizards occupy habitat based on thermal suitability over the duration of a field season. Given the low variability observed in thermal suitability layers, we question the ecological reality of these predictions. Correlative models may accurately describe the niche at small spatial scales, and may suffice in situations where time and financial resources are limiting constraints on project goals. Process-based information continues to be an important part of the niche, and may offer additional predictive accuracy via correlative approaches when included in an ecologically meaningful context

Cross-Cultural Study of Psychological Types at the Years of Emerging Adulthood

Emerging adulthood exists only in cultures that allow young people a prolonged period of independent social roles and exploration during the late teens and twenties. It is a period of the course of life that is culturally constructed, not universal or immutable (Arnett, 2000). This assumption led to the idea for comparison of this age in three cultures - Bulgarian, Hawaiian and New Zealand. The Myers-Briggs type indicator, Form G, was administered (Myers et al., 1998). The sample consisted of 289 respondents, aged 18-29, respectively the Bulgarians were 100, the Hawaiians were 89 and the New Zealanders were 100. Six SRTT comparisons were made. The results show that there were typological differences that distinguished the group of Bulgarians, aged 18-29, from their peers from Hawaii, USA and New Zealand. The specificity was expressed in preference to N, P, T, IN, NP, NT, IP, TP and INTP. This finding is largely consistent with the pursuit of new experience and opportunities, typical for the years of emerging adulthood. As well, there were some typological differences between the gender groups.Language: Bulgaria

Differences in substance use, sexual behavior, and demographic factors by level of outness to friends and family about being a male-for-male escort

Male sex work (i.e., escorting) is a stigmatized profession and men in the sex industry may hide their involvement to avoid negative social consequences. There is limited research comparing men who are out about being an escort to their friends and/or family with those out to neither friends nor family. Data were taken from a 2013 online study of male escorts who were categorized into three groups based on outness patterns—friends only (48.9%, n = 193), friends and family (26.6%, n = 105), or neither friends nor family (23.5%, n = 93)—and compared on demographic and behavioral variables. We hypothesized that men out to neither friends nor family would perform poorer across indicators of health and wellbeing due to the lack of social support that can come from friends and family. However, with the exception of reporting lower satisfaction and pay from their last male client, this hypothesis was unsupported. Outness patterns were largely unassociated with social and sexual behaviors with the last male client, and the majority eschewed condomless anal sex with their last male client, suggesting escorts—regardless of how out they are to friends and family—could navigate safer sex behaviors with their clients. Outness was associated with substance use (\u3c 12 months) and substance use with their last male client—men out to friends and family were, for the most part, the most likely to have used substances. Men out to friends and family were significantly more likely than others to have been escorting for greater than five years as well as escorting full-time. Interventions for escorts that address substance use and sexual risk behaviors that incorporate supportive friend and family social networks may be an important area for future research

Variation in Vital-rate Sensitivity Between Populations of Texas Horned Lizards

Demographic studies of imperiled populations can aid managers in planning conservation actions. However, applicability of findings for a single population across a species’ range is sometimes questionable. We conducted long-term studies (8 and 9 years, respectively) of 2 populations of the lizard Phrynosoma cornutum separated by 1000 km within the historical distribution of the species. The sites were a 15-ha urban wildlife reserve on Tinker Air Force Base (TAFB) in central Oklahoma and a 6000-ha wildland site in southern Texas, the Chaparral Wildlife Management Area (CWMA). We predicted a trade-off between the effect of adult survival and fecundity on population growth rate (λ), leading to population-specific contributions of individual vital rates to λ and individualized strategies for conservation and management of this taxon. The CWMA population had lower adult survival and higher fecundity than TAFB. As predicted, there was a trade-off in the effects of adult survival and fecundity on λ between the two sites; fecundity affected λ more at CWMA than at TAFB. However, adult survival had the smallest effect on λ in both populations. We found that recruitment in P. cornutum most affected λ at both sites, with hatchling survival having the strongest influence on λ. Management strategies focusing on hatchling survival would strongly benefit both populations. As a consequence, within the constraint of the need to more accurately estimate hatchling survival, managers across the range of species such as P. cornutum could adopt similar management priorities with respect to stage classes, despite intra-population differences in population vital rates

Stratified dispersal and increasing genetic variation during the invasion of Central Europe by the western corn rootworm, Diabrotica virgifera virgifera

Invasive species provide opportunities for investigating evolutionary aspects of colonization processes, including initial foundations of populations and geographic expansion. Using microsatellite markers and historical information, we characterized the genetic patterns of the invasion of the western corn rootworm (WCR), a pest of corn crops, in its largest area of expansion in Europe: Central and South-Eastern (CSE) Europe. We found that the invaded area probably corresponds to a single expanding population resulting from a single introduction of WCR and that gene flow is geographically limited within the population. In contrast to what is expected in classical colonization processes, an increase in genetic variation was observed from the center to the edge of the outbreak. Control measures against WCR at the center of the outbreak may have decreased effective population size in this area which could explain this observed pattern of genetic variation. We also found that small remote outbreaks in southern Germany and north-eastern Italy most likely originated from long-distance dispersal events from CSE Europe. We conclude that the large European outbreak is expanding by stratified dispersal, involving both continuous diffusion and discontinuous long-distance dispersal. This latter mode of dispersal may accelerate the expansion of WCR in Europe in the future