Biology subjects

Guedes, J. J. M.

Publications and source records attributed to Guedes, J. J. M..

4 recordsLinked to original sources

bioRxiv2026

Biodiversity material remains where capacity and governance are strong, but taxonomic resources concentrate with geopolitical power

AimBiodiversity-rich regions often lack the scientific infrastructure needed to document and curate their own biodiversity, creating inequalities in access to taxonomic reference material. We investigated how biological, institutional, and geopolitical factors shape the retention, extraction, and appropriation of reptile holotypes, the name-bearing specimens upon which species descriptions are based. LocationGlobal. TaxonReptiles. MethodsWe compiled a historical dataset of reptile holotype origins and destinations spanning 1758-2024 to reconstruct long-term patterns of retention and international specimen flows. We then quantified species-level holotype retention, holotype flows between country pairs, and country-level patterns of retention, appropriation, and network centrality for the period 1990-2024, and used generalised linear mixed models to assess the biological, institutional, and geopolitical determinants of these contemporary circulation processes. ResultsAlthough nearly 90% of reptile species described originated in the Global South, less than a quarter of their holotypes remain housed there. Historically, exported holotypes consistently outnumbered retained holotypes on a decadal basis until the early twenty-first century. Retention was promoted by local scientific capacity, institutional infrastructure, collector involvement in species descriptions, and environmental governance. In contrast, extraction was concentrated in highly endemic regions with limited scientific infrastructure and was associated with taxonomic revisions, socioeconomic interest, and disparities in political stability and colonial history. Appropriation of foreign holotypes was greatest in countries with high research investment, strong environmental governance, and historical geopolitical influence. Main conclusionsGlobal patterns of holotype circulation reflect a persistent geography of scientific inequality. The distribution of taxonomic reference material emerges from the interaction of retention, extraction, and appropriation processes, linking local biodiversity discovery to uneven global scientific capacity. Reducing these inequalities will require investments in taxonomic expertise, institutional infrastructure, and governance frameworks that promote more equitable stewardship of biodiversity knowledge and its material foundations.

ecology↗

bioRxiv2025

Historical shifts, geographic biases, and biological constraints shape mammal taxonomy

Species descriptions in taxonomy have become increasingly comprehensive, yet disparities persist across taxa and regions. We assess temporal trends in mammal species descriptions (1990-2025) using four proxies of comprehensiveness--counts of examined specimens and compared taxa, number of pages (only from the Methods/Results sections), and number of evidence lines (i.e., analytical tools and techniques). Using generalized linear models, we assessed how these proxies are explained by factors associated with species biology, geography, and taxonomic practice. Most new species derive from tropical regions, particularly rodents and bats, reflecting global discovery hotspots. Descriptions have grown more rigorous over time, with expanded specimen sampling, broader taxonomic comparisons, and integrative methods. However, disparities emerge along geographic and biological axes: descriptions from temperate regions incorporate more evidence lines, while small-bodied and tropical species (especially bats) remain understudied due to sampling biases and resource limitations. Body size inversely correlates with description length, as smaller species often require advanced diagnostics. Species-rich genera show greater comprehensiveness, likely due to heightened diagnostic scrutiny. Our findings highlight progress in taxonomic rigor but underscore persistent gaps tied to geography, body size, and accessibility of analytical tools. Addressing these disparities requires targeted investments in local capacity, equitable collaboration, and accessible methodologies to strengthen global taxonomic infrastructure and support conservation priorities.

zoology↗

bioRxiv2023

Correlates of time to first citation in ecology and taxonomy

Several metrics exists to evaluate the impact of publications and researchers, but most are based on citation counts, which usually fail to capture the temporal aspect of citations. Time to first citation represents a useful metric for research evaluation, and informs the speed at which scientific knowledge is disseminated through the scientific community. Understanding which factors affect such metrics is important as they impact resource allocation and career progression, besides influencing knowledge promotion across disciplines. Many ecological works rely on species identity, which is the coin of taxonomy. Despite its importance, taxonomy is a discipline in crisis lacking staff, funds and prestige, which ultimately may affect the evaluation and dissemination of taxonomic works. We used a time-to-event analysis to investigate whether taxonomic, socioeconomic, and scientometric factors influence first citation speed across hundreds of ecological and taxonomic articles. Time to first citation differed greatly between these areas. Ecological studies were first cited much faster than taxonomic studies. Multitaxa articles received first citations earlier than studies focused on single major taxonomic groups. Article length and h-index among authors were negatively correlated with time to first citation, while the number of authors, number of countries, and Gross Domestic Product was unimportant. Knowledge dissemination is faster for lengthy, multitaxa, and ecological articles relative to their respective counterparts, as well as for articles with highly prolific authors. We stress that using several unrelated metrics is desirable when evaluating research from different-and even related-disciplines, particularly in the context of professional progression and grant allocation.

scientific communication and education↗

bioRxiv2023

A phylogeny-informed characterization of global tetrapod traits addresses data gaps and biases

Tetrapods (amphibian, reptiles, birds and mammals) are model systems for global biodiversity science, but continuing data gaps, limited data standardisation, and ongoing flux in taxonomic nomenclature constrain integrative research on this group and potentially cause biased inference. We combined and harmonised taxonomic, spatial, phylogenetic, and attribute data with phylogeny-based multiple imputation to provide a comprehensive data resource (TetrapodTraits 1.0.0) that includes values, predictions, and sources for body size, activity time, micro- and macrohabitat, ecosystem, threat status, biogeography, insularity, environmental preferences and human influence, for all 33,281 tetrapod species covered in recent fully sampled phylogenies. We assess gaps and biases across taxa and space, finding that shared data missing in attribute values increased with taxon-level completeness and richness across clades. Prediction of missing attribute values using multiple imputation revealed substantial changes in estimated macroecological patterns. These results highlight biases incurred by non-random missingness and strategies to best address them. While there is an obvious need for further data collection and updates, our phylogeny--informed database of tetrapod traits can support a more comprehensive representation of tetrapod species and their attributes in ecology, evolution, and conservation research.

ecology↗