Aim Area thresholds, at which the form of the species–area relationship (SAR) changes abruptly, have played an important role in the theoretical framework of conservation biogeography and biodiversity research. The application of piecewise regressions has been advocated as a rigorous statistical technique to identify such thresholds within SARs, but a large variety of piecewise models remains untested. We explore the prevalence and number of thresholds in SARs and examine whether the currently widely used method for detecting the small island effect (SIE) is robust. Location Global. Taxon We consider all multicellular taxa based on the criteria of datasets selection. Methods We apply 15 regression models, including linear regression and piecewise regressions with two and three segments to 68 global island datasets that are sourced from the literature. Results The number of area thresholds in SARs varied among groups and correlated positively with area range of a studied system. Under the AIC or AIC c criterion, three‐segment piecewise models were more prevalent, whereas under the BIC criterion, two‐segment piecewise models were more prevalent. From the results of Aegean Sea isopods, West Indies herpetofauna, and Australian Islands mammals, we found evidence that the traditional criteria for detection of SIEs are not robust. Main conclusions Our study demonstrates that (a) to detect an SIE, the comparison should use as many models as possible, including not only variants with and without a left‐horizontal part, but also those with two and more segments; (b) naive use of the traditional two‐segment piecewise regressions may cause poor estimations of both slope and breakpoint values; (c) the number of thresholds increases with the area range of a studied system; (d) conservation biologists and applied ecologists should determine the number of area thresholds when estimating the precise species–area patterns and making management strategies in fragmented landscapes.

Hylomecon japonica is considered a natural medicinal plant with anti-inflammatory, anticancer and antibacterial activity. The assessment of climate change impact on its habitat suitability is important for the wild cultivation and standardized planting of H. japonica. In this study, the maximum entropy model (Maxent) and geographic information system (ArcGIS) were applied to predict the current and future distribution of H. japonica species, and the contributions of variables were evaluated by using the jackknife test. The area under the receiver operating characteristic curve (AUC) value confirmed the accuracy of the model prediction based on 102 occurrence records. The predicted potential distributions of H. japonica were mainly concentrated in Jilin, Liaoning, Shaanxi, Chongqing, Henan, Heilongjiang and other provinces (adaptability index > 0.6). The jackknife experiment showed that the precipitation of driest month (40.5%), mean annual temperature (12.4%), the precipitation of wettest quarter (11.6%) and the subclass of soil (9.7%) were the most important factors affecting the potential distribution of H. japonica. In the future, only under the shared socioeconomic Pathway 245 (SSP 245) scenario model in 2061–2080, the suitable habitat area for H. japonica is expected to show a significant upward trend. The area under other scenarios may not increase or decrease significantly.

Understanding biogeographic variation in species diversity patterns is important for conservation of biological diversity (Socolar et al., 2016;Vetaas & Grytnes, 2002). Elevational patterns of species richness, in recent decades, have received much attention in ecological and biogeographic studies (Brown,

The drama and film literature major is an important subject in the higher education system. With the continuous improvement of people's living standards, people's pursuit of spiritual and cultural levels has moved to a higher level. As a typical representative of artistic works, drama and film literature can not be created without the training of high-level talents. Colleges and universities shoulder the important task of cultivating talents for socialist modernization. How to do a good job in the reform of the construction of drama and film literature in colleges and universities in a new historical period is a problem worthy of attention of all educators. This article briefly discusses the problems in teaching reform and talent cultivation of drama and film literature major in colleges and universities and gives some measures to achieve the role of reference and improvement.

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