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Biological invasions pose a global challenge, affecting ecosystems worldwide and human societies. Knowledge of the evolutionary history of invasive species is critical to understanding their current invasion success and projecting their future spread. However, to date, few studies have addressed the evolutionary history and potential future spread of invaders simultaneously. In this study, we explored both evolutionary history and spatiotemporal dynamic patterns of the distribution of Reynoutria japonica, known as one of the world's worst plant invaders. We analysed 265 R. japonica samples from its current geographical ranges across three continents, using seven chloroplast DNA (cpDNA) markers to establish the phylogenetic relationships among extant populations. We combined these with ecological niche modelling to infer historical and more recent migration patterns and predict potential future distribution changes under climate change. Our results indicate that climate fluctuations and sea level changes likely facilitated the expansion of R. japonica from southern Japan to continental East Asia in the Pliocene, followed by a contraction in East Asian populations. In the recent Holocene, human activities have then enabled a linage of this species to spread from Japan to Europe and North America, resulting in three major global clades. Future climate scenarios suggest a northward expansion of R. japonica in Europe and North America, but shrinking habitat in China. Our study, thus, demonstrates the complex influences of historical climate‐driven migrations, human activities and future climate changes on the global distribution of an invasive species. [ABSTRACT FROM AUTHOR] more...

Invasive plant species pose significant ecological and economic threats due to their establishment and dominance in non-native ranges. Previous studies have yielded mixed results regarding the plants' adaptive mechanisms for thriving in new environments, and particularly, little is known about how the phenotypic plasticity of growth and defense-related traits may facilitate plant invasion. This study addressed these uncertainties by employing the aggressive weed Reynoutria japonica as a study model. We examined the differences in growth, defense-related traits and biomass allocation between R. japonica populations from native and introduced ranges grown in two common gardens with distinct climate conditions. Our results demonstrated that while the introduced populations did not exhibit increases in height and total dry mass, nor reductions in leaf defense levels, their investment in leaf production was significantly higher compared to the native populations. Additionally, introduced populations displayed greater phenotypic plasticity in clonal ramet but less phenotypic plasticity in biomass production than native populations across varying environments. These findings highlight the roles of phenotypic plasticity and specific trait adaptations, such as clonality, in the successful invasion of R. japonica. This study has important implications for managing invasive plant species under changing environmental conditions. [ABSTRACT FROM AUTHOR] more...

Like alien plant invasion, range expansion of native plants may threaten biodiversity and economies, rendering them native invaders. Variation in abiotic and biotic conditions across a large geographic scale greatly affects variation in traits and interactions with herbivores of native plant invaders, which is an interesting yet mostly unexplored issue. We used a common garden experiment to compare defensive/nutritional traits and palatability to generalist herbivores of 20 native (23.64° N–30.18° N) and introduced range (31.58° N–36.87° N) populations of Reynoutria japonica, which is a native invader following range expansion in China. We analyzed the relationships among herbivore pressure, climate, plant chloroplast haplotypes, leaf traits, and herbivore performance. Of the 16 variables tested, we observed range differences in 11 variables and latitudinal clines in nine variables. In general, herbivores performed better on the introduced plants than on the native plants, and better on the high‐latitude plants than on the low‐latitude plants within the introduced populations. Three key traits (leaf thickness, specific leaf area, and carbon‐to‐nitrogen [C:N] ratio) determined palatability to herbivores and were significantly associated with temperature and/or precipitation of plant provenance as well as with plant haplotypes but not with herbivore pressure. Our results revealed a causal sequence from plant‐range‐based environmental forces and genetic context to plant quality and palatability to herbivores in R. japonica. These findings suggest a post‐introduction evolution of R. japonica, which may partly explain the colonization success of this important native, but invasive plant. [ABSTRACT FROM AUTHOR] more...

Objective: To evaluate a method of measuring the change in palatal length and shape following maxillary advancement using synchronous lateral videofluoroscopy and voice recording in order to understand how movement of the maxilla may affect VPI risk in patients with cleft lip and/or palate (CL/P). Design: Retrospective cohort study of children with cleft lip and/or palate. Setting: Single center, tertiary children's hospital. Participants: Patients with cleft lip and/or palate who underwent maxillary advancement between 2016–21 inclusive. Interventions: Maxillary advancement surgery, including those who underwent concurrent mandibular procedures. Main outcome measures: The length of the soft palate and the genu angle were measured throughout palatal dynamic range. Pre- and post-operative measurements were compared using a one sided T-test, with subgroup analysis for patients with clinical VPI. Results: Ten patients were examined. The mean distance of maxillary advancement was 10.5 mm. The average increase in pre-genu soft palate length was 2.8 mm in the resting position and 2.9 mm in the closed position. The genu angle decreased in the closed position by 16.3 degrees. Conclusions: The soft palate showed limited ability to lengthen following maxillary advancement and this may explain the risk of VPI. There was partial compensation by the muscle sling of the palate as demonstrated by a more acute post-operative genu angle and this suggests one reason for the variability of VPI reported. Future research is required to investigate how length and shape changes measured using this method can predict VPI risk. [ABSTRACT FROM AUTHOR] more...