Directional Selection on Tree Seedling Traits Driven by Experimental Drought Differs Between Mesic and Dry Populations

We evaluated population differences and drought-induced phenotypic selection on four seedling traits of the Australian forest tree Eucalyptus pauciflora using a glasshouse dry-down experiment. We compared dry and mesic populations and tested for directional selection on lamina length (reflecting leaf size), leaf shape, the node of ontogenetic transition to the petiolate leaf (reflecting the loss of vegetative juvenility), and lignotuber size (reflecting a recovery trait). On average, the dry population had smaller and broader leaves, greater retention of the juvenile leaf state and larger lignotubers than the mesic population, but the populations did not differ in seedling survival. While there was statistical support for directional selection acting on the focal traits in one or other population, and for differences between populations in selection gradient estimates for two traits, only one trait—lamina length—exhibited a pattern of directional selection consistent with the observed population differences being a result of past adaptation to reduce seedling susceptibility to acute drought. The observed directional selection for lamina length in the mesic population suggests that future increases in drought risk in the wild will shift the mean of the mesic population toward that of the dry population. Further, we provide evidence suggesting an early age trade-off between drought damage and recovery traits, with phenotypes which develop larger lignotubers early being more susceptible to drought death. Such trade-offs could have contributed to the absence of population mean differences in survival, despite marked differentiation in seedling traits.

Genetic stability of Aedes aegypti populations following invasion by wMel Wolbachia

Background Wolbachia wMel is the most commonly used strain in rear and release strategies for Aedes aegypti mosquitoes that aim to inhibit the transmission of arboviruses such as dengue, Zika, Chikungunya and yellow fever. However, the long-term establishment of wMel in natural Ae. aegypti populations raises concerns that interactions between Wolbachia wMel and Ae. aegypti may lead to changes in the host genome, which could affect useful attributes of Wolbachia that allow it to invade and suppress disease transmission. Results We applied an evolve-and-resequence approach to study genome-wide genetic changes in Ae. aegypti from the Cairns region, Australia, where Wolbachia wMel was first introduced more than 10 years ago. Mosquito samples were collected at three different time points in Gordonvale, Australia, covering the phase before (2010) and after (2013 and 2018) Wolbachia releases. An additional three locations where Wolbachia replacement happened at different times across the last decade were also sampled in 2018. We found that the genomes of mosquito populations mostly remained stable after Wolbachia release, with population differences tending to reflect the geographic location of the populations rather than Wolbachia infection status. However, outlier analysis suggests that Wolbachia may have had an influence on some genes related to immune response, development, recognition and behavior. Conclusions Ae. aegypti populations remained geographically distinct after Wolbachia wMel releases in North Australia despite their Wolbachia infection status. At some specific genomic loci, we found signs of selection associated with Wolbachia, suggesting potential evolutionary impacts can happen in the future and further monitoring is warranted.

ADHD in women - a review

Introduction: Attention-deficit hyperactivity disorder (ADHD) for many years has been thought to occur mainly in the male population. However, recent studies and change in professionals' perception allowed us to understand that there are significant differences between predominant features related to the gender of the affected person, which changes our look at how the condition may exhibit in women. Current state of knowledge: In this review, we provide a general look at the disorder, its characteristics in the young and adult population, differences in symptoms and finally - how it may prove difficult to diagnose this condition among women. Several factors that could contribute to development of ADHD were listed in literature, among them genetics, prenatal period, diet and parents’ emotional wellbeing. Concerning women, they are considered to internalize their psychological struggles, such as depression and stress more often than men, rendering them more susceptible toward suicidal behaviors and making diagnosis harder. Conclusions: When it comes to diagnosis in women, the main difficulty is that the symptoms are presented in a different way compared to men suffering from the same disorder. Because of those reasons, it’s harder to make a proper diagnosis. Therefore, further studies, taking account of affected one’s gender needs to be conducted, while medical professionals have to be more cautious.

The apportionment of citations: A scientometric analysis of Lewontin, 1972

"The Apportionment of Human Diversity" (1972) is the most highly cited research article published by geneticist Richard Lewontin in his career. This study's primary result--that most genetic diversity in humans can be accounted for by within-population differences, not between-population differences--along with Lewontin's outspoken, politically-charged interpretations thereof, has become foundational to the scientific and cultural discourse pertaining to human genetic variation. The article has an unusual bibliometric trajectory in that it is much more salient in the bibliographic record today compared to the first 20 years after its publication. Here, we show how the paper's fame was shaped by four factors: 1) citations in influential publications across several disciplines; 2) Lewontin's own popular books and media appearances; 3) the renaissance of population genetics research of the early 1990s; and 4) the serendipitous collision of scientific progress, influential books/papers, and heated controversies in the year 1994. We conclude with an analysis of Twitter data to characterize the communities and conversations that continue to keep this study at the epicenter of discussions about race and genetics, prompting new challenges for scientists who have inherited Lewontin's legacy.

Prevalence of Hyperacusis in the General and Special Populations: A Scoping Review

Objectives: To study the prevalence of hyperacusis in the general population and the special population, and to determine the effect of population differences on hyperacusis.Methods: The two authors followed a scoping review methodology and screened nearly 30 years of English literature in Pubmed, Web of Science, OVID, and EBSCO. Then, the extracted results of each study were discussed in groups and subgroups.Results: The authors selected 42 pieces of scientific literature that met the requirements, studying a total of 34,796 subjects, including the general population (28,425 subjects), the special occupation population (2,746 subjects), and the patients with concomitant diseases (5,093 subjects). The prevalence was 0.2–17.2% in the general population, 3.8–67% in the special occupation population, and 4.7–95% in the patients with special diseases. It was found that in the general population, the high prevalence occurs in adolescents and older adults. The prevalence of hyperacusis in women is significantly higher than in men. In people with hearing disorders, the prevalence of hyperacusis is significantly higher than in people with normal hearing. Various diseases (such as Williams syndrome, tinnitus, and autism), as well as various occupations (musicians, music students, teachers, and others), have been found to be high risk factors for hyperacusis.Conclusion: The high prevalence of hyperacusis and the large differences between reported prevalence in different studies deserves our great attention. Additionally, in order to increase the comparability of the studies, a standardized set of criteria are needed to study the prevalence of hyperacusis.

Diversity of leaf anatomy within a single leaflet and between leaflets of four Butia (Arecaceae, Arecoideae) species

This paper is an investigation into how the anatomy changes within a leaflet and between the leaflets of a single leaf blade of Butia. Four species of Butia were studied: Butia paraguayensis, B. eriospatha, B. yatay and B. odorata. Changes in the anatomical characters are important because some have been used in keys to help separate the species. Recently, anatomical mid-rib characters were used in a key to separate species of Butia. We found that characters, such as abaxially projected or rounded mid-rib fibrous ring or number and arrangement of accessory bundles, do change within a single leaflet or between the leaflets of a single leaf blade. Growing conditions and leaf developmental maturity are also important factors that influence leaflet anatomy and may cause one to be misled in an identification key based on anatomical characters. We re-emphasize the importance of always sampling from the same part of the leaf, to have a broader sampling, be attentive to the environmental condition and health of the plant from which you are sampling and to consider population differences.