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Accurate information on species range contraction is the cornerstone of effective biodiversity conservation. The eastern indigo snake (Drymarchon couperi) is an apex predator in Florida and, similar to many species native to Florida, is threatened by widespread habitat destruction. Environmental deoxyribonucleic acid (eDNA) monitoring of this elusive snake would provide a non‐invasive approach to improve our knowledge of the species' range and distribution. We designed and tested an eDNA assay that can detect the presence of D. couperi from soil samples from their natural scrub habitat in Florida. We validated our assay in silico, in vitro, and in situ. Furthermore, we investigated the influence of temperature and humidity on the degradation rate of eDNA over time. We successfully amplified the cytochrome b gene for D. couperi at concentrations as low as 3 × 10−3 ng/μL and successfully detected the presence of D. couperi in 2 of 30 in situ field soil samples. The degradation experiment resulted in detectable DNA for 10 days. Interestingly, temperature and humidity had no effect on the degradation rate of eDNA in our experimental conditions. This study provides support for soil eDNA applications to detect the presence of a federally threatened species in their natural environment bolstering our ability to monitor the conservation and management of imperiled species. Environmental DNA provides an additional conservation tool to quickly and effectively monitor species range shifts driven by multiple anthropogenic stressors to promote the persistence of imperiled species. [ABSTRACT FROM AUTHOR]

Figural effect is a response bias that depends on the arrangement of the terms in syllogisms. The usual pattern in construction tasks is that participants tend to give A-C responses when the syllogisms are in figure 4(A-B/B-C), while the majority of their conclusions are in the opposite direction (C-A) for syllogisms in figure 1 (B-A/C-B). We report on one experiment that examines the role of the presentation format of premises (two-line presentation vs. one-line presentation) in categorical syllogisms. The experiment showed that when premises were presented in one-line presentation format, participants generated more A-C than C-A conclusions in all syllogistic figures. However, when premises were presented in twoline presentation format, participants generated more A-C conclusions in figure 4 and more C-A conclusions in figure 1, while there were no reliable differences for either figure 2 (A-B/C-B) or figure 3(B-A/B-C). We discuss the implications of these results for different theories of reasoning.

Recent phylogeographic studies of poorly-dispersing coastal invertebrates in highly biodiverse regions have led to the discovery of high levels of cryptic diversity and complex phylogeographic patterns that suggest isolation, geological, and ecological processes have shaped their biodiversity. Studies of southern African coastal invertebrates have uncovered cryptic diversity for various taxa and phylogeographic patterns that, although sharing some similarities across taxa, do differ. These findings underscore the need for additional studies to better understand the biodiversity levels, distributional patterns, and processes responsible for producing coastal biodiversity in that region. The coastal isopod Deto echinata is of particular interest, as its complex taxonomic history, poor dispersal capabilities, and broad geographic distribution suggest the potential for cryptic diversity. We use mitochondrial and nuclear sequences to characterize D. echinata individuals from localities ranging from northern Namibia to Glentana, about 2,500 km along the coastline on the south coast of South Africa. These are used to assess whether D. echinata harbors cryptic genetic diversity and whether phylogeographic distributional patterns correlate with those previously documented for other coastal isopods in the region. Analysis of mitochondrial and nuclear sequences revealed two deeply-divergent lineages that exhibit a distributional break in the Cape Peninsula region. These findings suggest D. echinata is a cryptic species complex in need of taxonomic revision and highlight the need for further taxonomic and phylogeographic studies of similarly poorly-dispersing coastal invertebrates in southern Africa. [ABSTRACT FROM AUTHOR]

In this study, the authors introduce a new way to analyze cognitive change during social interactions, based on the mental model theory of reasoning. From this approach, cognitive performance can be improved for solving problems that require multiple models when participants in a social interaction group maintain qualitatively different models of a problem. Four relational reasoning experiments are reported. In Experiment 1 with school-aged participants, the authors found better performance for the social interaction groups on a posttest. Experiment 2 with younger children, in which models had been induced, showed that when the models of participants in the social interaction group were different, there was better performance. However, these results did not generalize to the posttest. Experiments 3 and 4 provide additional support for the idea that maintaining qualitatively different models leads to better performance even when participants work alone in a self-interaction situation.

An eye-movement monitoring experiment was carried out to examine the effects of the difficulty of the problem (simple versus complex problems) and the type of figure (figure 1 or figure 4) on the time course of processing categorical syllogisms. The results showed that the course of influence for these two factors is different. We found early processing effects for the figure but not for the difficulty of the syllogism and later processing effects for both the figure and the difficulty. These results lend support to the Model Theory (Johnson-Laird, P. N., Byrne, R. M. J. (1991). Deduction. Hillsdale, New Jersey: LEA.) as opposed to other theories of reasoning (Chater, N., Oaksford, M. (1999). The probability heuristics model of syllogistic reasoning. Cognitive Psychology, 38, 191-258; Rips, L. J. (1994). The psychology of proof. Cambridge, MA: MIT Press; Rips, L. J. (1994). The psychology of proof. Cambridge, MA: MIT Press).

The authors examined in 3 experiments the comprehension of counterfactuals, such as "If it had rained, the plants would have bloomed," and semifactuals, such as "Even if it had rained, the plants would have bloomed," compared with indicative conditionals, "If it rained, the plants bloomed." The first experiment showed that people read the negative conjunction, "not p and not q" faster when it was primed by a counterfactual than when it was primed by an indicative conditional. They read the affirmative conjunction, "p and q" equally quickly when it was primed by either conditional. The 2nd experiment showed that people read the negated-antecedent conjunction, "not p and q" faster when it was primed by a semifactual conditional. The 3rd experiment corroborated these results in a direct comparison of counterfactuals and semifactuals. The authors discuss the implications of the results for the mental representations of different conditionals.