Lethal trap created by adaptive evolutionary response to an exotic resource.

Global transport of organisms by humans provides novel resources to wild species, which often respond maladaptively. Native herbivorous insects have been killed feeding on toxic exotic plants, which acted as 'ecological traps'1-4. We document a novel 'eco-evolutionary trap' stemming from the opposite effect; that is, high fitness on an exotic resource despite lack of adaptation to it. Plantago lanceolata was introduced to western North America by cattle-ranching. Feeding on this exotic plant released a large, isolated population of the native butterfly Euphydryas editha from a longstanding trade-off between maternal fecundity and offspring mortality. Because of this release-and despite a reduced insect developmental rate when feeding on this exotic-Plantago immediately supported higher larval survival than did the insects' traditional host, Collinsia parviflora 5 . Previous work from the 1980s documented an evolving preference for Plantago by ovipositing adults 6 . We predicted that if this trend continued the insects could endanger themselves, because the availability of Plantago to butterflies is controlled by humans, who change land management practices faster than butterflies evolve 6 . Here we report the fulfilment of this prediction. The butterflies abandoned Collinsia and evolved total dependence on Plantago. The trap was set. In 2005, humans withdrew their cattle, springing the trap. Grasses grew around the Plantago, cooling the thermophilic insects, which then went extinct. This local extinction could have been prevented if the population had retained partial use of Collinsia, which occupied drier microhabitats unaffected by cattle removal. The flush of grasses abated quickly, rendering the meadow once again suitable for Euphydryas feeding on either host, but no butterflies were observed from 2008 to 2012. In 2013-2014, the site was naturally recolonized by Euphydryas feeding exclusively on Collinsia, returning the system to its starting point and setting the stage for a repeat of the anthropogenic evolutionary cycle.

Preference Provides a Plethora of Problems (Don't Panic).

This review was solicited as an autobiography. The "problems" in my title have two meanings. First, they were professional difficulties caused by my decision to study oviposition preferences of butterflies that were not susceptible to traditional preference-testing designs. Until I provided video, my claim that the butterflies duplicate natural post-alighting host-assessment behavior when placed on hosts by hand was not credible, and the preference-testing technique that I had developed elicited skepticism, anger, and derision. The second meaning of "problems" is scientific. Insect preference comes with complex dimensionality that interacts with host acceptability. Part Two of this review describes how my group's work in this area has revealed unexpected axes of variation in plant-insect interactions-axes capable of frustrating attempts to derive unequivocal conclusions from apparently sensible experimental designs. The possibility that these complexities are lurking should be kept in mind as preference and performance experiments are devised.

Colonizations cause diversification of host preferences: A mechanism explaining increased generalization at range boundaries expanding under climate change.

As species' poleward range limits expand under climate change, generalists are expected to be better colonists than specialists, extending their ranges faster. This effect of specialization on range shifts has been shown, but so has the reverse cause-effect: in a global meta-analysis of butterfly diets, it was range expansions themselves that caused increases in population-level diet breadth. What could drive this unexpected process? We provide a novel behavioral mechanism by showing that, in a butterfly with extensive ecotypic variation, Edith's checkerspot, diet breadths increased after colonization events as diversification of individual host preferences pulled novel hosts into population diets. Subsequently, populations that persisted reverted toward monophagy. We draw together three lines of evidence from long-term studies of 15 independently evolving populations. First, direct observations showed a significant increase in specialization across decades: in recent censuses, eight populations used fewer host genera than in the 1980s while none used more. Second, behavioral preference-testing experiments showed that extinctions and recolonizations at two sites were followed, at first by diversification of heritable preference ranks and increases in diet breadth, and subsequently by homogenization of preferences and contractions of diet breadth. Third, we found a significant negative association in the 1980s between population-level diet breadth and genetic diversity. Populations with fewer mtDNA haplotypes had broader diets, extending to 3-4 host genera, while those with higher haplotype diversity were more specialized. We infer that diet breadth had increased in younger, recently colonized populations. Preference diversification after colonization events, whether caused by (cryptic) host shifts or by release of cryptic genetic variation after population bottlenecks, provides a mechanism for known effects of range shifts on diet specialization. Our results explain how colonizations at expanding range margins have increased population-level diet breadths, and predict that increasing specialization should accompany population persistence as current range edges become range interiors.

Impact of a specialty trained billing team on an academic otolaryngology practice.

PURPOSE: To determine how the incorporation of specialty specific training for coders within a focused billing team affected revenue, efficiency, time to reimbursement, and physician satisfaction in an academic otolaryngology practice. MATERIALS AND METHODS: Our academic otolaryngology department recently implemented a new billing system, which incorporated additional training in otolaryngology surgical procedures for medical coders. A mixed model analysis of variance was used to compare billing outcomes for the 6 months before and 6 months after this new approach was initiated. The following metrics were analyzed: Current Procedural Terminology codes, total charges, time between services rendered and billing submission, and time to reimbursement. A survey of department physicians assessing satisfaction with the system was reviewed. RESULTS: There were 4087 Current Procedural Terminology codes included in the analysis. In comparing the periods before and after implementation of the new system, statistically significant decreases were found in the mean number of days to coding completion (19.3 to 12.0, respectively, p < 0.001), days to posting of charges (27.0 to 15.2, p < 0.001), days to final reimbursement (54.5 to 27.2, p < 0.001), and days to closure of form (179.2 to 76.6, p < 0.001). Physician satisfaction with communication and coder feedback increased from 36% to 64% after initiation of the new program. CONCLUSIONS: The implementation of additional specialty training for medical coders in the otolaryngology department of a large medical system was associated with improved revenue cycle efficiency. Additionally, this model appears to improve physician satisfaction and confidence with the coding system.

A faster parathyroidectomy: Techniques to shorten non-surgical operating room time.

OBJECTIVE: To assess the capacity of different techniques to reduce non-operative times during parathyroid surgery. The impact of monitored anesthesia care (MAC) instead of general anesthesia, and the pre-operative placement of a second peripheral intravenous catheter (PIV) were analyzed. METHODS: A retrospective case series at an academic medical center was performed to study patients undergoing parathyroidectomy by a single surgeon between November 2013 and October 2016. Three operating room (OR) time measurements were compared: pre-incision time, post-closure time, and total OR time. RESULTS: Surgeries performed under MAC (n = 21) had statistically shorter pre-incision (33.2 min vs. 39.7 min, p < .001), post-closure (10.1 min vs. 16.2 min, p = .002), and total operative times (113.0 min vs. 151.5 min, p < .001) compared to those in which general anesthesia (n = 169) was used. Of the 169 patients who underwent general anesthesia, 25 had a second PIV placed preoperatively and 144 had only a single PIV. All 3 time periods were statistically shorter in patients who had a second PIV versus those who had only a single PIV (pre-incision 32.2 min vs. 41.0 min, p < .001; post-closure 12.2 min vs. 16.9 min, p < .001; total 117.9 min vs. 157.4 min, p < .001). CONCLUSIONS: In patients undergoing parathyroid surgery in which ioPTH levels will be used, the placement of a second PIV in the pre-operative holding area and performance of surgery under MAC can significantly shorten non-operative and total OR time.

INCIDENTAL THYROID NODULES: RACE/ETHNICITY DISPARITIES AND OUTCOMES.

OBJECTIVE: Black patients have a significantly lower incidence of well-differentiated thyroid cancer (WDTC) compared to all other race/ethnic groups, while white patients appear to be at greater risk. This study examines incidental thyroid nodules (ITNs) to assess whether racial disparities in WDTC arise from a differential discovery of ITNs-perhaps due to socioeconomic disparities-or reflect true differences in thyroid cancer rates. METHODS: A retrospective review was performed of all patients who underwent fine-needle aspiration (FNA) of thyroid nodules by our academic medical center's endocrinology division between January 2006 and December 2010. Medical records were reviewed to identify whether the biopsied thyroid nodule was discovered incidentally through nonthyroid-related imaging or identified by palpation. RESULTS: FNAs were performed on 1,369 total thyroid nodules in 1,141 study patients; 547 (48%) were classified as white, and 593 (52%) were classified as nonwhite. Among this cohort, 36.6% of patients underwent biopsy for an ITN. White patients were 1.6 times more likely to have undergone a biopsy for a nodule that was incidentally identified compared to nonwhites ( P<.0001). Indicators of socioeconomic status (SES) did not have a significant association with ITNs. Within the ITN cohort, 4.9% of nonwhite patients were found to have a thyroid malignancy compared to 12.9% of white patients ( P<.01). CONCLUSION: The higher incidence of thyroid cancer in white patients appears to be not only due to diagnostic bias, but also to a true difference in cancer prevalence. ABBREVIATIONS: FNA = fine-needle aspiration; ITN = incidental thyroid nodule; SEER = Surveillance Epidemiology and End Results; SES = socioeconomic status; WDTC = well-differentiated thyroid cancer.

Remote Access Robotic Facelift Thyroidectomy: A Multi-institutional Experience.

BACKGROUND: Robotic facelift thyroidectomy (RFT) was developed as a new surgical approach to the thyroid gland using a remote incision site. Early favorable results led to this confirmatory multi-institutional experience. METHODS: Prospectively collected data on consecutive patients undergoing RFT in five North American academic endocrine surgical practices were compiled. Surgical indications, operative times, final pathology, nodule size, complications, and postoperative management (drain use and length of hospital stay) were evaluated. RESULTS: A total of 102 RFT procedures were undertaken in 90 patients. All but one of the patients (98.9 %) were female, and the mean age was 41.9 ± 13.1 years (range 12-69 years). The indication for surgery was nodular disease in 91.2 % of cases; 8.8 % were completion procedures performed for a diagnosis of cancer. The mean size of the largest nodule was 1.9 cm (range 0-5.6 cm). The mean total operative time for a thyroid lobectomy was 162 min (range 82-265 min). No permanent complications occurred. There were 4 cases (3.9 %) of transient recurrent laryngeal nerve weakness, no cases of hypocalcemia, and 3 (2.9 %) hematomas. There were no conversions to an anterior cervical approach. The majority of patients were managed on an outpatient basis (61.8 %) and without a drain (65.7 %). CONCLUSIONS: RFT is technically feasible and safe in selected patients. RFT can continue to be offered to carefully selected patients as a way to avoid a visible cervical scar. Future prospective studies to compare this novel approach to other remote access approaches are warranted.

Incision Planning in Thyroid Compartment Surgery: Getting it Perfect.

OBJECTIVE: This study evaluated changes in thyroid compartment incision site locations with patient positioning to define a reliable method for placing the scar in the optimal vertical location. METHODS: The optimal incision location was marked with the patient sitting upright before surgery. The distance from the sternal notch to this mark was measured with the patient in the upright, supine, and final surgical positions. RESULTS: Complete data were available for 104 procedures. The mean distances from the sternal notch to the incision site were 4.8, 21.5, and 31.9 mm in the sitting, supine, and surgical positions, respectively. Each of these distances were significantly different from one another (P<.0001) and were independent of patient age, sex, body mass index (BMI), or height. CONCLUSIONS: Cutaneous cervical landmarks migrate significantly during patient positioning. Marking the thyroid compartment incision site while the patient is in an upright position results in a more predictable final scar location.

Defining anatomical landmarks for robotic facelift thyroidectomy.

BACKGROUND: Robotic facelift thyroidectomy (RFT) is a straightforward remote access thyroidectomy technique. While the anatomy encountered during RFT is well known to surgeons, the vector of approach during this technique may be less familiar. In order to facilitate safe and efficient performance of RFT, the relationships of key anatomical landmarks associated with this technique were determined. METHODS: Eight anatomical dissections were performed in cadavers and included performance of RFT and definition of discrete anatomical relationships. Morphologic assessments of the great auricular nerve (GAN), omohyoid (OH) muscle, inferior constrictor (IC) muscle, and recurrent laryngeal nerve (RLN) were conducted. RESULTS: The mean distance from the incision apex to the anterior and posterior aspects of the GAN were 3.8 ± 1.2 and 7.7 ± 0.8 cm. From the apex of the incision to the OH muscle was 11.1 ± 1.7 cm on average. The OH muscle was located 1.3 ± 0.5 cm inferior to an axial line drawn through the inferior aspect of the thyroid notch. The anterior branch of the RLN was identified coursing deep to the inferior margin of the IC muscle a mean of 1.2 ± 0.2 cm lateral to the origin of this muscle on the cricoid cartilage. CONCLUSIONS: Characterization of the key anatomical landmarks of the lateral neck and thyroid compartment associated with RFT, including the GAN, OH muscle, and RLN, allows for rapid recognition of these critical structures during this operation. Surgeons learning this approach should be familiar with these relationships.

Intraoperative Parathyroid Hormone Monitoring In Normohormonal Primary Hyperparathyroidism: How Low Do You Go?

OBJECTIVE: The primary goal of this study was to determine in patients with normohormonal primary hyperparathyroidism (NHHPT) what percent reduction in post-excision intraoperative parathyroid hormone (IOPTH) from baseline would yield a rate of cure comparable to that in patients with classical primary hyperparathyroidism (PHPT). METHODS: This is a retrospective cohort study of patients who underwent parathyroidectomy between July 2013 and February 2020. Demographic data, preoperative, intraoperative, and postoperative metrics were collected. Patients with NHHPT were compared to those with classical PHPT. Subgroup analyses were performed. RESULTS: Of the 496 patients included in the study, 66 (13.3%) were of the normohormonal variant based on preoperative intact parathyroid hormone (PTH) levels and 28 (5.6%) based on baseline IOPTH levels. The cure rates in the two normohormonal groups were not significantly different from their classical counterparts (98.4% and 100.0% vs. 97.1%, p = 1.000). The median percent decline in post-excision IOPTH from baseline that achieved cure in the normohormonal groups were 82.6% and 80.4% compared to their respective controls at 87.3%, p = 0.011 and p = 0.001. Although the rate of multiglandular disease was higher in one of the normohormonal variant groups, this difference was due to a higher rate of double adenomas, not four-gland hyperplasia. CONCLUSION: Patients with NHHPT undergoing parathyroidectomy can expect cure rates similar to that in patients with classical PHPT. The results of this study indicate that achieving an 80% drop or more in IOPTH levels predicts a high likelihood of cure. This is true irrespective of whether the patient is deemed normohormonal based on preoperative or intraoperative testing. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:2480-2484, 2024.

Molecular Alterations and Comprehensive Clinical Management of Oncocytic Thyroid Carcinoma: A Review and Multidisciplinary 2023 Update.

Importance: Oncocytic (Hürthle cell) thyroid carcinoma is a follicular cell-derived neoplasm that accounts for approximately 5% of all thyroid cancers. Until recently, it was categorized as a follicular thyroid carcinoma, and its management was standardized with that of other differentiated thyroid carcinomas. In 2022, given an improved understanding of the unique molecular profile and clinical behavior of oncocytic thyroid carcinoma, the World Health Organization reclassified oncocytic thyroid carcinoma as distinct from follicular thyroid carcinoma. The International Thyroid Oncology Group and the American Head and Neck Society then collaborated to review the existing evidence on oncocytic thyroid carcinoma, from diagnosis through clinical management and follow-up surveillance. Observations: Given that oncocytic thyroid carcinoma was previously classified as a subtype of follicular thyroid carcinoma, it was clinically studied in that context. However, due to its low prevalence and previous classification schema, there are few studies that have specifically evaluated oncocytic thyroid carcinoma. Recent data indicate that oncocytic thyroid carcinoma is a distinct class of malignant thyroid tumor with a group of distinct genetic alterations and clinicopathologic features. Oncocytic thyroid carcinoma displays higher rates of somatic gene variants and genomic chromosomal loss of heterozygosity than do other thyroid cancers, and it harbors unique mitochondrial DNA variations. Clinically, oncocytic thyroid carcinoma is more likely to have locoregional (lymph node) metastases than is follicular thyroid carcinoma-with which it was formerly classified-and it develops distant metastases more frequently than papillary thyroid carcinoma. In addition, oncocytic thyroid carcinoma rarely absorbs radioiodine. Conclusions and Relevance: The findings of this review suggest that the distinct clinical presentation of oncocytic thyroid carcinoma, including its metastatic behavior and its reduced avidity to radioiodine therapy, warrants a tailored disease management approach. The reclassification of oncocytic thyroid carcinoma by the World Health Organization is an important milestone toward developing a specific and comprehensive clinical management for oncocytic thyroid carcinoma that considers its distinct characteristics.

Beyond climate change attribution in conservation and ecological research.

There is increasing pressure from policymakers for ecologists to generate more detailed 'attribution' analyses aimed at quantitatively estimating relative contributions of different driving forces, including anthropogenic climate change (ACC), to observed biological changes. Here, we argue that this approach is not productive for ecological studies. Global meta-analyses of diverse species, regions and ecosystems have already given us 'very high confidence' [sensu Intergovernmental Panel on Climate Change (IPCC)] that ACC has impacted wild species in a general sense. Further, for well-studied species or systems, synthesis of experiments and models with long-term observations has given us similarly high confidence that they have been impacted by regional climate change (regardless of its cause). However, the role of greenhouse gases in driving these impacts has not been estimated quantitatively. Should this be an ecological research priority? We argue that development of quantitative ecological models for this purpose faces several impediments, particularly the existence of strong, non-additive interactions among different external factors. However, even with current understanding of impacts of global warming, there are myriad climate change adaptation options already developed in the literature that could be, and in fact are being, implemented now.

Host-associated genomic differentiation in congeneric butterflies: now you see it, now you do not.

Ecotypic variation among populations may become associated with widespread genomic differentiation, but theory predicts that this should happen only under particular conditions of gene flow, selection and population size. In closely related species, we might expect the strength of host-associated genomic differentiation (HAD) to be correlated with the degree of phenotypic differentiation in host-adaptive traits. Using microsatellite and Amplified Fragment Length Polymorphism (AFLP) markers, and controlling for isolation by distance between populations, we sought HAD in two congeneric species of butterflies with different degrees of host plant specialization. Prior work on Euphydryas editha had shown strong interpopulation differentiation in host-adapted traits, resulting in incipient reproductive isolation among host-associated ecotypes. We show here that Euphydryas aurinia had much weaker host-associated phenotypic differentiation. Contrary to our expectations, we detected HAD in Euphydryas aurinia, but not in E. editha. Even within an E. aurinia population that fed on both hosts, we found weak but significant sympatric HAD that persisted in samples taken 9 years apart. The finding of significantly stronger HAD in the system with less phenotypic differentiation may seem paradoxical. Our findings can be explained by multiple factors, ranging from differences in dispersal or effective population size, to spatial variation in genomic or phenotypic traits and to structure induced by past histories of host-adapted populations. Other infrequently measured factors, such as differences in recombination rates, may also play a role. Our result adds to recent work as a further caution against assumptions of simple relationships between genomic and adaptive phenotypic differentiation.

Field studies reveal strong postmating isolation between ecologically divergent butterfly populations.

Gene flow between populations that are adapting to distinct environments may be restricted if hybrids inherit maladaptive, intermediate phenotypes. This phenomenon, called extrinsic postzygotic isolation (EPI), is thought to play a critical role in the early stages of speciation. However, despite its intuitive appeal, we know surprisingly little about the strength and prevalence of EPI in nature, and even less about the specific phenotypes that tend to cause problems for hybrids. In this study, we searched for EPI among allopatric populations of the butterfly Euphydryas editha that have specialized on alternative host plants. These populations recall a situation thought typical of the very early stages of speciation. They lack consistent host-associated genetic differentiation at random nuclear loci and show no signs of reproductive incompatibility in the laboratory. However, they do differ consistently in diverse host-related traits. For each of these traits, we first asked whether hybrids between populations that use different hosts (different-host hybrids) were intermediate to parental populations and to hybrids between populations that use the same host (same-host hybrids). We then conducted field experiments to estimate the effects of intermediacy on fitness in nature. Our results revealed strong EPI under field conditions. Different-host hybrids exhibited an array of intermediate traits that were significantly maladaptive, including four behaviors. Intermediate foraging height slowed the growth of larvae, while intermediate oviposition preference, oviposition site height, and clutch size severely reduced the growth and survival of the offspring of adult females. We used our empirical data to construct a fitness surface on which different-host hybrids can be seen to fall in an adaptive valley between two peaks occupied by same-host hybrids. These findings demonstrate how ecological selection against hybrids can create a strong barrier to gene flow at the early stages of adaptive divergence.

Emerging Imaging Technologies for Parathyroid Gland Identification and Vascular Assessment in Thyroid Surgery: A Review From the American Head and Neck Society Endocrine Surgery Section.

Importance: Identification and preservation of parathyroid glands (PGs) remain challenging despite advances in surgical techniques. Considerable morbidity and even mortality result from hypoparathyroidism caused by devascularization or inadvertent removal of PGs. Emerging imaging technologies hold promise to improve identification and preservation of PGs during thyroid surgery. Observation: This narrative review (1) comprehensively reviews PG identification and vascular assessment using near-infrared autofluorescence (NIRAF)-both label free and in combination with indocyanine green-based on a comprehensive literature review and (2) offers a manual for possible implementation these emerging technologies in thyroid surgery. Conclusions and Relevance: Emerging technologies hold promise to improve PG identification and preservation during thyroidectomy. Future research should address variables affecting the degree of fluorescence in NIRAF, standardization of signal quantification, definitions and standardization of parameters of indocyanine green injection that correlate with postoperative PG function, the financial effect of these emerging technologies on near-term and longer-term costs, the adoption learning curve and effect on surgical training, and long-term outcomes of key quality metrics in adequately powered randomized clinical trials evaluating PG preservation.

Geographic mosaics of species' association: a definition and an example driven by plant-insect phenological synchrony.

Spatial mosaics occur in both evolutionary and ecological properties of species' interactions. Studies of these patterns have facilitated description and prediction of evolutionary responses of interacting species to each other and to changing environments. We propose seeking complementary understanding of community assembly and dynamics by studying ecological and mechanistic properties of mosaics. We define "species' association mosaics" as deviations from a null model in which spatial variation in the extent to which particular species interact ecologically is explained solely by variation in their densities. In extreme deviations from the null, a focal species interacts exclusively with different partners at different sites despite similar abundances of potential partners. We investigate this type of mosaic involving the butterfly Euphydryas editha and its hosts, the perennial Pedicularis semibarbata (Psem) and the ephemeral annual Collinsia torreyi (Ctor). A reciprocal transplant experiment showed that the proximate, mechanistic driver of the mosaic was variation in butterfly oviposition preference: the identity of the preferred host species depended on the site of origin of the insects, not that of the plants. In contrast, the evolutionary driver was phenological asynchrony between the insects and Ctor. Censuses showed that larvae hatching from eggs laid on Ctor would have suffered significantly greater mortality from host senescence at five sites where Ctor was avoided than at two sites where it was used. These differences among sites in phenological synchrony were caused by variation in life span of Ctor. At sites where Ctor was avoided, natural selection on host preference was stabilizing because Ctor life span was too short to accommodate the development time of most larvae. At sites where Ctor was used, selection on preference was also stabilizing because larvae lacked physiological adaptation to feed on Psem. These reciprocal forces of stabilizing selection formed a mosaic maintaining spatial variation in insect host preference that was the proximate cause of the species-association mosaic. In the Discussion, we examine the extent to which our findings hindcast an observed anthropogenic host shift by E. editha from Psem to Ctor. This example shows that elucidation of species-association mosaics can facilitate understanding of community evolution and dynamics.

Mosaics of climatic stress across species' ranges: tradeoffs cause adaptive evolution to limits of climatic tolerance.

Studies in birds and trees show climatic stresses distributed across species' ranges, not only at range limits. Here, new analyses from the butterfly Euphydryas editha reveal mechanisms generating these stresses: geographic mosaics of natural selection, acting on tradeoffs between climate adaptation and fitness traits, cause some range-central populations to evolve to limits of climatic tolerance, while others remain resilient. In one ecotype, selection for predator avoidance drives evolution to limits of thermal tolerance. In a second ecotype, the endangered Bay Checkerspot, selection on fecundity drives evolution to the climate-sensitive limit of ability to complete development within the lifespans of ephemeral hosts, causing routinely high mortality from insect-host phenological asynchrony. The tradeoff between maternal fecundity and offspring mortality generated similar values of fitness on different dates, partly explaining why fecundity varied by more than an order of magnitude. Evolutionary response to the tradeoff rendered climatic variability the main driver of Bay Checkerspot dynamics, and increases in this variability, associated with climate change, were a key factor behind permanent extinction of a protected metapopulation. Finally, we discuss implications for conservation planning of our finding that adaptive evolution can reduce population-level resilience to climate change and generate geographic mosaics of climatic stress. This article is part of the theme issue 'Species' ranges in the face of changing environments (Part II)'.

A better index for analysis of co-occurrence and similarity.

Scientists often need to know whether pairs of entities tend to occur together or independently. Standard approaches to this issue use co-occurrence indices such as Jaccard, Sørensen-Dice, and Simpson. We show that these indices are sensitive to the prevalences of the entities they describe and that this invalidates their interpretability. We propose an index, α, that is insensitive to prevalences. Published datasets reanalyzed with both α and Jaccard's index (J) yield profoundly different biological inferences. For example, a published analysis using J contradicted predictions of the island biogeography theory finding that community stability increased with increasing physical isolation. Reanalysis of the same dataset with the estimator [Formula: see text] reversed that result and supported theoretical predictions. We found similarly marked effects in reanalyses of antibiotic cross-resistance and human disease biomarkers. Our index α is not merely an improvement; its use changes data interpretation in fundamental ways.

Human-nature connectedness as a pathway to sustainability: A global meta-analysis.

Internationally agreed sustainability goals are being missed. Here, we conduct global meta-analyses to assess how the extent to which humans see themselves as part of nature-known as human-nature connectedness (HNC)-can be used as a leverage point to reach sustainability. A meta-analysis of 147 correlational studies shows that individuals with high HNC had more pronature behaviours and were significantly healthier than those with low HNC. A meta-analysis of 59 experimental studies shows significant increases in HNC after manipulations involving contact with nature and mindfulness practices. Surprisingly, this same meta-analysis finds no significant effect of environmental education on HNC. Thus, HNC is positively linked to mind-sets that value sustainability and behaviours that enhance it. Further, we argue that HNC can be enhanced by targeted practices, and we identify those most likely to succeed. Our results suggest that enhancing HNC, via promotion of targeted practices, can improve sustainability and should be integrated into conservation policy.