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Species are the currency of most biodiversity studies. However, many shortfalls and biases remain in our biodiversity estimates, preventing a comprehensive understanding of the eco-evolutionary processes that have shaped the biodiversity currently available on Earth. Biased biodiversity estimates also jeopardize the effective implementation of data-driven conservation strategies, ultimately leading to biodiversity loss. Here, we delve into the concept of the Latitudinal Taxonomy Gradient (LTG) and show how this new idea provides an interesting conceptual link between the Linnean (i.e., our ignorance of how many species there are on Earth), Darwinian (i.e., our ignorance of species evolutionary relationships), and Wallacean (i.e., our ignorance on species distribution) shortfalls. More specifically, we contribute to an improved understanding of LTGs and establish the basis for the development of new methods that allow us to: (i) better account for the integration between different shortfalls and, (ii) estimate how these interactions may affect our understanding about the evolutionary components of richness gradients at macroecological scales.

Copyright of Journal of Biogeography is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Marine chondrichthyans are experiencing a global decline, but identifying appropriate conservation actions is challenging due to the lack of basic biological information, such as growth parameters and reproduction. In this study, we identify biological and ecological attributes that can be both easily obtainable and are effective predictors of extinction threat.A bioecological attribute database was constructed for marine chondrichthyan species, including information on maximum length, habitat, reproductive mode, trophic level and conservation status, among others. Data sources included the Shark‐References, IUCN and FishBase databases. Following this, a generalized linear model was built with conservation status as the response variable and bioecological attributes as explanatory variables, and the model's accuracy was tested for each group. Then, the model was applied to species not yet classified (data deficient [DD] or not evaluated [NE]) to determine their probability of extinction risk.In total, data were compiled for 1225 species of marine Chondrichthyes (537 sharks, 636 rays and 52 chimaeras); approximately 20% of these species are classified as DD or NE. The model demonstrated high accuracy overall: 95% for chimaeras, 77% for rays and 72% for sharks. Our analysis indicates that, among the species that are classified as DD or NE, 58% of rays, 44% of sharks and 66% of chimaeras may be at risk of extinction.These results clearly demonstrate how bioecological attributes can serve as proxies of extinction risk in Chondrichthyes and provide a solid foundation for conservation planning and prioritization for this ecologically important yet data poor taxon. [ABSTRACT FROM AUTHOR]

Aim: Insects are one of the least studied taxa, with most species lacking basic ecological and biogeographical information. This problem is particularly acute in the tropics, where low sampling effort hampers accurate estimates of species richness at scale and potentially confounds efforts to identify the drivers of biogeographical gradients. Here, we evaluate the quality of the data on the distribution and diversity of odonate species in the Neotropics, while also examining the influence of sampling completeness on climate–richness relationships using a comprehensive database of odonates. Location: The Neotropics. Taxon: Odonata. Methods: Using 56,535 records collected from 1970 to 2021, we assess whether climate–species richness models vary under different scenarios of survey completeness. Results: Our survey compilation revealed that most Neotropical diversity of Odonata likely remains unknown. Only 1% of the one‐degree cells covering the Neotropics held reliable information on odonate species richness, with particularly severe gaps in the Caribbean, Central America, northeastern Brazil and northern Chile. Temperature, precipitation and potential evapotranspiration exert consistent effects on Odonata richness across the entire Neotropics, regardless the level of survey completeness. Whereas seasonality‐related variables are less important predictors of species richness at the biogeographical scale. Main Conclusions: By highlighting areas where inventories are more reliable and identifying regions that require increased data collection efforts and mobilization, our assessment offers a roadmap for improving the reliability of odonate inventories in the Neotropics. Furthermore, our findings underscore the importance of accounting for varying levels of survey completeness in macroecological models to reveal robust climate–species richness relationships. Simultaneously, they highlight strong climatic predictors of species richness, irrespective of survey effort intensity. These predictors provide a solid foundation for modelling and predicting odonate species richness in the Neotropics. [ABSTRACT FROM AUTHOR]

Antillean manatees (Trichechus manatus manatus) are endangered coastal, marine, and riverine megaherbivores with high environmental plasticity, constrained by tidal and seasonal water level cycles that affect access to food and fresh water. Accurate quantification of the species' habitat requirements, typically achieved through home range (HR) estimation, is required to implement area‐based conservation initiatives. In this study, we used GPS tracking data from 38 wild and captive‐rehabilitated released manatees to estimate HR using autocorrelated kernel density estimators (AKDE) and average time speed. We investigated whether body size, habitat type, sex and behavioural group influence home range size due to energy requirements, resources availability, a scramble‐competitive polygyny mating system, and adaptation to the wild. Eighteen manatees exhibited range‐resident behaviour, with a mean 95% home range of 72.96 km2 (± 218.52) and a median of 10.69 km2. The mean daily speed was estimated to be 13.47 km/day (± 4.16). Home range and body size were positively correlated, consistent with HR allometry theory. Long‐term tracked individuals showed a trend of increasing HR over time. Only four released animals (17.4%) were range‐resident, suggesting that they may need additional time to establish a home range. Individuals using only the marine environment had larger home ranges compared to mixed (marine and estuarine) and estuarine environments, probably due to freshwater availability. Our study contributes to the understanding of the factors driving manatee movement and provides more accurate estimates of area requirements, which can inform the establishment and zoning of marine protected areas. [ABSTRACT FROM AUTHOR]

Islands are biodiversity hotspots that host unique assemblages. However, a substantial proportion of island species are threatened and their long‐term survival is uncertain. Identifying and preserving vulnerable species has become a priority, but it is also essential to combine this information with other facets of biodiversity like functional diversity, to understand how future extinctions might affect ecosystem stability and functioning. Focusing on mammals, we (i) assessed how much functional space would be lost if threatened species go extinct, (ii) determined the minimum number of extinctions that would cause a significant functional loss, (iii) identified the characteristics (e.g., biotic, climatic, geographic, or orographic) of the islands most vulnerable to future changes in the functional space, and (iv) quantified how much of that potential functional loss would be offset by introduced species. Using trait information for 1474 mammal species occurring in 318 islands worldwide, we built trait probability density functions to quantify changes in functional richness and functional redundancy in each island if the mammals categorized by IUCN as threatened disappeared. We found that the extinction of threatened mammals would reduce the functional space in 63% of the assessed islands, although these extinctions in general would cause a reduction of less than 15% of their overall functional space. Also, on most islands, the extinction of just a few species would be sufficient to cause a significant loss of functional diversity. The potential functional loss would be higher on small, isolated, and/or species‐rich islands, and, in general, the functional space lost would not be offset by introduced species. Our results show that the preservation of native species and their ecological roles remains crucial for maintaining the current functioning of island ecosystems. Therefore, conservation measures considering functional diversity are imperative to safeguard the unique functional roles of threatened mammal species on islands. [ABSTRACT FROM AUTHOR]

Flagship species are an important tool for mobilizing support for conservation. Here, we extend this concept to include individual organisms, whose characteristics, fates, and connections to people can garner public attention, attract conservation support, and spur activism. Flagship individuals typically share a similar suite of characteristics, including (1) species‐level traits associated with charisma; (2) individual traits that are unique or distinctive; (3) a high degree of exposure to humans; and (4) a known, noteworthy life history or fate. The interplay between these characteristics and human agency establishes unique connections between flagship individuals and people, and generates widespread media attention. We discuss how the selection and promotion of flagship individuals can inspire empathy and, ultimately, conservation action. Finally, we identify the limitations of the flagship individual approach, while arguing that, if carefully and strategically implemented, it has the potential to produce substantial benefits for conservation policy and practice. [ABSTRACT FROM AUTHOR]

Copyright of Conservation Biology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)