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Adaptive radiation is the rise of a diversity of ecological roles and role-specific adaptations within a lineage. Recently, some researchers have begun to use ‘adaptive radiation’ or ‘radiation’ as synonymous with ‘explosive species diversification’. This essay aims to clarify distinctions between these concepts, and the related ideas of geographic speciation, sexual selection, key innovations, key landscapes and ecological keys. Several examples are given to demonstrate that adaptive radiation and explosive diversification are not the same phenomenon, and that focusing on explosive diversification and the analysis of phylogenetic topology ignores much of the rich biology associated with adaptive radiation, and risks generating confusion about the nature of the evolutionary forces driving species diversification. Some ‘radiations’ involve bursts of geographic speciation or sexual selection, rather than adaptive diversification; some adaptive radiations have little or no effect on speciation, or even a negative effect. Many classic examples of ‘adaptive radiation’ appear to involve effects driven partly by geographic speciation, species' dispersal abilities, and the nature of extrinsic dispersal barriers; partly by sexual selection; and partly by adaptive radiation in the classical sense, including the origin of traits and invasion of adaptive zones that result in decreased diversification rates but add to overall diversity.

The adaptive radiations of East African cichlid fish in the Great Lakes Victoria, Malawi, and Tanganyika are well known for their diversity and repeatedly evolved phenotypes. Convergent evolution of melanic horizontal stripes has been linked to a single locus harboring the gene agouti-related peptide 2 (agrp2). However, where and when the causal variants underlying this trait evolved and how they drove phenotypic divergence remained unknown. To test the alternative hypotheses of standing genetic variation versus de novo mutations (independently originating in each radiation), we searched for shared signals of genomic divergence at the agrp2 locus. Although we discovered similar signatures of differentiation at the locus level, the haplotypes associated with stripe patterns are surprisingly different. In Lake Malawi, the highest associated alleles are located within and close to the 5′ untranslated region of agrp2 and likely evolved through recent de novo mutations. In the younger Lake Victoria radiation, stripes are associated with two intronic regions overlapping with a previously reported cis-regulatory interval. The origin of these segregating haplotypes predates the Lake Victoria radiation because they are also found in more basal riverine and Lake Kivu species. This suggests that both segregating haplotypes were present as standing genetic variation at the onset of the Lake Victoria adaptive radiation with its more than 500 species and drove phenotypic divergence within the species flock. Therefore, both new (Lake Malawi) and ancient (Lake Victoria) allelic variation at the same locus fueled rapid and convergent phenotypic evolution.

Background Glioblastoma (GBM) is an aggressive primary brain tumor with a high recurrence rate despite multimodal treatment approaches. Adaptive radiation therapy (ART) involves adjusting the treatment plan based on tumor and resection cavity changes during radiotherapy, potentially improving treatment precision while reducing radiation exposure to normal brain tissue. However, the clinical outcomes and recurrence patterns associated with ART remain unclear. We aimed to evaluate the efficacy of ART for GBM treatment, focusing on survival outcomes and recurrence patterns. Methods We retrospectively analyzed a prospectively collected cohort of 59 patients with pathologically confirmed GBM who received postoperative three-dimensional conformal radiotherapy (3D-CRT)–based ART between April 2015 and November 2018. Mid-treatment magnetic resonance imaging was performed after delivery of 34–36 Gy. Based on these images, an offline single-time-point ART boost plan was generated to accommodate changes in tumor size and the resection cavity. Radiotherapy consisted of 40 Gy in 20 fractions to the initial target, followed by a 20 Gy boost in f10 fractions (total 60 Gy in 30 fractions over six weeks). Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan–Meier method. Recurrence patterns were classified by the spatial relationship between recurrent tumor volume and the 95% isodose line. Results During a median follow-up period of 19.2 (range, 2.1–81.6) months, 36 patients (61.0%) experienced tumor recurrence, and 32 (54.2%) died. The 1- and 2-year OS rates were 93.9% and 54.6%, respectively, with a median OS of 26.6 months. The 6- and 12-month PFS rates were 71.1% and 46.1%, respectively, with a median PFS of 10.5 months. Central recurrence was the most common pattern (29 patients, 78%), followed by distant (5 patients, 14%) and in-field recurrences (3 patients, 8%). Marginal recurrence was not observed. No cases of grade 2 or higher radiation necrosis were observed, and only two cases of grade 1 radiation necrosis were identified. Conclusions ART for GBM is associated with favorable survival outcomes and low toxicity. ART does not increase the risk of marginal recurrence, and the incidence of radiation necrosis is low. Further studies are required to optimize ART protocols to maximize their clinical benefits.

Adaptive radiations (ARs) frequently show remarkable repeatability where single lineages undergo multiple independent episodes of AR in distant places and long-separate time points. Genetic variation generated through hybridization between distantly related lineages can promote AR. This mechanism, however, requires rare coincidence in space and time between a hybridization event and opening of ecological opportunity, because hybridization generates large genetic variation only locally and it will persist only for a short period. Hence, hybridization seems unlikely to explain recurrent AR in the same lineage. Contrary to these expectations, our evolutionary computer simulations demonstrate that admixture variation can geographically spread and persist for long periods if the hybrid population becomes separated into isolated sub-lineages. Subsequent secondary hybridization of some of these can reestablish genetic polymorphisms from the ancestral hybridization in places far from the birthplace of the hybrid clade and long after the ancestral hybridization event. Consequently, simulations revealed conditions where exceptional genetic variation, once generated through a rare hybridization event, can facilitate multiple ARs exploiting ecological opportunities available at distant points in time and space.

Radiotherapy has been demonstrated to be one of the most significant treatments for cervical cancer, during which accurate and efficient delineation of target volumes is critical. To alleviate the data demand of deep learning and promote the establishment and promotion of auto-segmentation models in small and medium-sized oncology departments and single centres, we proposed an auto-segmentation algorithm to determine the cervical cancer target volume in small samples based on multi-decoder and semi-supervised learning (MDSSL), and we evaluated the accuracy via an independent test cohort. In this study, we retrospectively collected computed tomography (CT) datasets from 71 pelvic cervical cancer patients, and a 3:4 ratio was used for the training and testing sets. The clinical target volumes (CTVs) of the primary tumour area (CTV1) and pelvic lymph drainage area (CTV2) were delineated. For definitive radiotherapy (dRT), the primary gross target volume (GTVp) was simultaneously delineated. According to the data characteristics for small samples, the MDSSL network structure based on 3D U-Net was established to train the model by combining clinical anatomical information, which was compared with other segmentation methods, including supervised learning (SL) and transfer learning (TL). The dice similarity coefficient (DSC), 95% Hausdorff distance (HD95) and average surface distance (ASD) were used to evaluate the segmentation performance. The ability of the segmentation algorithm to improve the efficiency of online adaptive radiation therapy (ART) was assessed via geometric indicators and a subjective evaluation of radiation oncologists (ROs) in prospective clinical applications. Compared with the SL model and TL model, the proposed MDSSL model displayed the best DSC, HD95 and ASD overall, especially for the GTVp of dRT. We calculated the above geometric indicators in the range of the ground truth (head-foot direction). In the test set, the DSC, HD95 and ASD of the MDSSL model were 0.80/5.85 mm/0.95 mm for CTV1 of post-operative radiotherapy (pRT), 0.84/ 4.88 mm/0.73 mm for CTV2 of pRT, 0.84/6.58 mm/0.89 mm for GTVp of dRT, 0.85/5.36 mm/1.35 mm for CTV1 of dRT, and 0.84/4.09 mm/0.73 mm for CTV2 of dRT, respectively. In a prospective clinical study of online ART, the target volume modification time (MTime) was 3–5 min for dRT and 2–4 min for pRT, and the main duration of CTV1 modification was approximately 2 min. The introduction of the MDSSL method successfully improved the accuracy of auto-segmentation for the cervical cancer target volume in small samples, showed good consistency with RO delineation and satisfied clinical requirements. In this prospective online ART study, the application of the segmentation model was demonstrated to be useful for reducing the target volume delineation time and improving the efficiency of the online ART workflow, which can contribute to the development and promotion of cervical cancer online ART.

Why diversification rates vary so extensively across the tree of life remains an important yet unresolved issue in biology. Two prominent and potentially independent factors proposed to explain these trends reflect the capacity of lineages to expand into new areas of (i) geographical or (ii) ecological space. Here, we present the first global assessment of how diversification rates vary as a consequence of geographical and ecological expansion, studying these trends among 15 speciose passerine families (together approximately 750 species) using phylogenetic path analysis. We find that relative slowdowns in diversification rates characterize families that have accumulated large numbers of co-occurring species (at the 1° scale) within restricted geographical areas. Conversely, more constant diversification through time is prevalent among families in which species show limited range overlap. Relative co-occurrence is itself also a strong predictor of ecological divergence (here approximated by morphological divergence among species); however, once the relationship between co-occurrence and diversification rates have been accounted for, increased ecological divergence is an additional explanatory factor accounting for why some lineages continue to diversify towards the present. We conclude that opportunities for prolonged diversification are predominantly determined by continued geographical range expansion and to a lesser degree by ecological divergence among lineages.

Premise of the Study Evolutionary and biogeographic history, including past environmental change and diversification processes, are likely to have influenced the expansion, migration, and extinction of populations, creating evolutionary legacy effects that influence regional species pools and the composition of communities. We consider the consequences of the diversification process in shaping trait evolution and assembly of oak‐dominated communities throughout the continental United States (U.S.). Methods Within the U.S. oaks, we tested for phylogenetic and functional trait patterns at different spatial scales, taking advantage of a dated phylogenomic analysis of American oaks and the U.S. Forest Service (USFS) Forest Inventory and Analysis (FIA). Key Results We find (1) phylogenetic overdispersion at small grain sizes throughout the U.S. across all spatial extents and (2) a shift from overdispersion to clustering with increasing grain sizes. Leaf traits have evolved in a convergent manner, and these traits are clustered in communities at all spatial scales, except in the far west, where species with contrasting leaf types co‐occur. Conclusions Our results support the hypotheses that (1) interspecific interactions were important in parallel adaptive radiation of the genus into a range of habitats across the continent and (2) that the diversification process is a critical driver of community assembly. Functional convergence of complementary species from distinct clades adapted to the same local habitats is a likely mechanism that allows distantly related species to coexist. Our findings contribute to an explanation of the long‐term maintenance of high oak diversity and the dominance of the oak genus in North America.

Background The aim of the present study is to examine the impact of kV-CBCT-based online adaptive radiation therapy (ART) on dosimetric parameters in comparison to image-guided-radiotherapy (IGRT) in consecutive patients with tumors in the head and neck region from a prospective registry. Methods The study comprises all consecutive patients with tumors in the head and neck area who were treated with kV-CBCT-based online ART or IGRT-modus at the linear-accelerator ETHOS™. As a measure of effectiveness, the equivalent-uniform-dose was calculated for the CTV (EUD CTV ) and organs-at-risk (EUD OAR ) and normalized to the prescribed dose. As an important determinant for the need of ART the interfractional shifts of anatomic landmarks related to the tongue were analyzed and compared to the intrafractional shifts. The latter determine the performance of the adapted dose distribution on the verification CBCT2 postadaptation. Results Altogether 59 consecutive patients with tumors in the head-and-neck-area were treated from 01.12.2021 to 31.01.2023. Ten of all 59 patients (10/59; 16.9%) received at least one phase within a treatment course with ART. Of 46 fractions in the adaptive mode, irradiation was conducted in 65.2% of fractions with the adaptive-plan, the scheduled-plan in the remaining. The dispersion of the distributions of EUD CTV -values from the 46 dose fractions differed significantly between the scheduled and adaptive plans (Ansari-Bradley-Test, p  = 0.0158). Thus, the 2.5th percentile of the EUD CTV -values by the adaptive plans amounted 97.1% (95% CI 96.6–99.5%) and by the scheduled plans 78.1% (95% CI 61.8–88.7%). While the EUD CTV for the accumulated dose distributions stayed above 95% at PTV-margins of ≥ 3 mm for all 8 analyzed treatment phases the scheduled plans did for margins ≥ 5 mm. The intrafractional anatomic shifts of all 8 measured anatomic landmarks were smaller than the interfractional with overall median values of 8.5 mm and 5.5 mm ( p  < 0.0001 for five and p  < 0.05 for all parameters, pairwise comparisons, signed-rank-test). The EUD OAR -values for the larynx and the parotid gland were significantly lower for the adaptive compared with the scheduled plans (Wilcoxon-test, p  < 0.001). Conclusions The mobile tongue and tongue base showed considerable interfractional variations. While PTV-margins of 5 mm were sufficient for IGRT, ART showed the potential of decreasing PTV-margins and spare dose to the organs-at-risk.

Background Daily adaptive radiation therapy (ART) of patients with non-small cell lung cancer (NSCLC) lowers organs at risk exposure while maintaining the planning target volume (PTV) coverage. Thus, ART allows an isotoxic approach with increased doses to the PTV that could improve local tumor control. Herein we evaluate daily online ART strategies regarding their impact on relevant dose-volume metrics. Methods Daily cone-beam CTs (1 × n = 28, 1 × n = 29, 11 × n = 30) of 13 stage III NSCLC patients were converted into synthetic CTs (sCTs). Treatment plans (TPs) were created retrospectively on the first-fraction sCTs (sCT 1 ) and subsequently transferred unaltered to the sCTs of the remaining fractions of each patient (sCT 2−n ) (IGRT scenario). Two additional TPs were generated on sCT 2−n : one minimizing the lung-dose while preserving the D 95% (PTV) (isoeffective scenario), the other escalating the D 95% (PTV) with a constant V 20Gy (lung ipsilateral ) (isotoxic scenario). Results Compared to the original TPs predicted dose, the median D 95% (PTV) in the IGRT scenario decreased by 1.6 Gy ± 4.2 Gy while the V 20Gy (lung ipsilateral ) increased in median by 1.1% ± 4.4%. The isoeffective scenario preserved the PTV coverage and reduced the median V 20Gy (lung ipsilateral ) by 3.1% ± 3.6%. Furthermore, the median V 5% (heart) decreased by 2.9% ± 6.4%. With an isotoxic prescription, a median dose-escalation to the gross target volume of 10.0 Gy ± 8.1 Gy without increasing the V 20Gy (lung ipsilateral ) and V 5% (heart) was feasible. Conclusions We demonstrated that even without reducing safety margins, ART can reduce lung-doses, while still reaching adequate target coverage or escalate target doses without increasing ipsilateral lung exposure. Clinical benefits by means of toxicity and local control of both strategies should be evaluated in prospective clinical trials.

Background Adaptive radiation therapy (ART) allows real-time treatment plan adjustment based on daily anatomical changes but involves a time-consuming workflow. Surface-guided radiation therapy (SGRT) provides precise patient positioning and intra-fractional motion management. This study retrospectively analyses intra-fractional patient motion using SGRT during long-duration radiotherapy (RT) like ART for prostate cancer and further assesses the relation for internal target position measured by cone-beam CT (CBCT) and surface position measured by SGRT. Methods Thirty ultra-hypo-fractionated prostate cancer patients (137 fractions) treated with ART on Ethos (version 1.0, Varian Medical Systems, Siemens Healthineers, Palo Alto, CA, USA) using a ring-mounted SGRT system (AlignRT inBore, Vision RT Ltd., UK) were retrospectively analyzed. The mean and standard deviation values of surface positions across three translational axes of up to 60 min of treatment were analyzed. Further, the translational shifts from the second daily CBCT before irradiation and surface position data were compared to evaluate the agreement between internal and surface position. Correlations between CBCT shifts and SGRT data were assessed with the Wilcoxon paired samples test. Results The maximum mean (± SD) surface motion was − 2.21 ± 1.27 mm (vertical, at 45 min), 0.22 ± 1.55 mm (longitudinal, at 35 min), and 0.16 ± 0.77 mm (lateral, at 20 min). After the second CBCT shift, the mean (± SD) surface position deviations were − 0.63 ± 1.43 mm (vertical), -0.24 ± 1.63 mm (longitudinal), and 0.05 ± 0.87 mm (lateral) with ranges of 8.30 mm, 10.02 mm, and 6.08 mm on the vertical, longitudinal, and lateral axes, respectively. Significant differences ( p  < 0.05) were found between CBCT and SGRT on the vertical and longitudinal axes. Conclusions SGRT revealed a consistent vertical shift over the whole course of long-duration RT and not only for the first minutes of the treatment. Further, SGRT exclusively is not an adequate inter-fractional positioning tool for prostate cancer patients, however additional SGRT-based intra-fractional monitoring can add a value for long duration RT.