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Many butterfly populations respond negatively to land-use intensification in human-dominated landscapes. However, networks of protected sites have been established with the aim to halt species loss.We undertook annual surveys of all populations of 22 uncommon butterfly species in eastern Denmark during the period 2014-2019 and compared to a systematic atlas survey done 1989-1993, in order to assess trends in regional occupancy of species.Three out of 22 species went regionally extinct between 1993 and 2015. One species sustained a single population through the study period. Logistic regression for the remaining 18 species showed 10 to be in strong decline from 1993 to 2015, two showed a declining trend and six had stable trends. For all species except one, the declining trend continued 2015-2019. For five species, a sustained strong decline was evident.In 1993, the total count of populations for all 22 butterfly species was 565, which by 2019 had declined to 158 populations (a 72 % loss over 26 years). From 2015 to 2019, the total count of populations further shrank from 200 to 158 (a 21 % decline over just four years).Legal protection of areas (Natura 2000 and Danish Nature Protection Act §3) was, unexpectedly, not associated with lower probability of local extinction for butterfly population. The observed sustained decline across species suggests an overall low efficiency of the network of protected sites, probably due to a combination of misguided management regimes and payment of extinction debts from the past.

Parchment was used as a writing material in the Middle Ages and was made using animal skins by liming them with Ca(OH)2. During liming, collagen peptides containing Glutamine (Q) undergo deamidation resulting in a mass shift of 0.984 Da. Assessing the extent of deamidation can inform us about parchment production patterns and quality. In this study, we propose a simple three-step workflow, developed as an R package called MALDIpqi(), to estimate deamidation in parchment derived collagen using low-resolution MALDI-TOF spectra. After pre-processing raw spectra, we used weighted least-squares linear regression to estimate Q deamidation levels from the convoluted isotopic envelope for seven collagen-peptide markers. Finally, we employed a linear mixed effect model to predict the overall deamidation level of a parchment sample termed Parchment Glutamine Index (PQI). To test the robustness of the workflow, we applied MALDIpqi() to previously published ZooMS data generated from almost an entire library of the Cistercian monastery at Orval Abbey, Belgium. In addition to reliably predicting PQI, we observed interesting patterns pertaining to parchment production. MALDIpqi() holds excellent potential for biocodicological and other archaeological studies involving collagen, such as bone, but we also foresee its application in the food and biomedical industry.

Ecological theory hypothesizes that plant trait diversity may be as important as the presence of specific functional traits (e.g., resistance) for the herbivore and predator communities within a population. We used experimental populations of wild woodland strawberry (Fragaria vesca) to test whether the degree of plant genotypic diversity and/or the existence of specific resistance traits play a role in the host plant’s community structure specifically, the community of generalist and specialist aphids and their natural enemies. In 2019, we studied the aphid abundance and relative predator abundance in an experimental field site in Alnarp, Southern Sweden; the field consisted of plots planted with combinations of 20 different wild strawberry genotypes. These strawberry genotypes were previously identified as either susceptible to or resistant against the herbivorous beetle (Galerucella tenella). Two aphid species, Chaetosiphon fragaefolii (specialist) and the exotic Aphis gossypii (generalist) were found in the plots and of the two species A. gossypii was dominant. The abundance of the specialist aphid (C. fragaefolii) was highest in susceptible plots with high genotypic diversity, while the generalist (A. gossypii) was highest in plots with a mix of resistant and susceptible plants with high genotypic diversity. Anthocorid predators, developed significantly higher population densities in strawberry plots with high genotypic diversity. Overall, predator abundance showed a positive correlation with aphid abundance. These results show that the specific functional trait of resistance as well as plant diversity affected aphids. Knowledge about these effects can be important factors to consider when designing strawberry plantings less susceptible to aphids.

Hypothesis testing is a key part of empirical science and multiple testing as well as the combination of evidence from several tests are continued areas of research. In this article we consider the problem of combining the results of multiple hypothesis tests to i) test global hypotheses and ii) make marginal inference while controlling the k-FWER. We propose a new family of combination tests for joint hypotheses, called the 'Too Many, Too Improbable' (TMTI) statistics, which we show through simulation to have higher power than other combination tests against many alternatives. Furthermore, we prove that a large family of combination tests -- which includes the one we propose but also other combination tests -- admits a quadratic shortcut when used in a Closed Testing Procedure, which controls the FWER strongly. We develop an algorithm that is linear in the number of hypotheses for obtaining confidence sets for the number of false hypotheses among a collection of hypotheses and an algorithm that is cubic in the number of hypotheses for controlling the k-FWER for any k greater than one.

Datasets are sometimes divided into distinct subsets, e.g. due to multi-center sampling, or to variations in instruments, questionnaire item ordering or mode of administration, and the data analyst then needs to assess whether a joint analysis is meaningful. The Principal Component Analysis-based Data Structure Comparisons (PCADSC) tools are three new non-parametric, visual diagnostic tools for investigating differences in structure for two subsets of a dataset through covariance matrix comparisons by use of principal component analysis. The PCADCS tools are demonstrated in a data example using European Social Survey data on psychological well-being in three countries, Denmark, Sweden, and Bulgaria. The data structures are found to be different in Denmark and Bulgaria, and thus a comparison of for example mean psychological well-being scores is not meaningful. However, when comparing Denmark and Sweden, very similar data structures, and thus comparable concepts of well-being, are found. Therefore, inter-country comparisons are warranted for these countries.