Felipe Osmari Cerezer

Understanding how ecological pressures and allometry contribute to morphological evolution remains a central goal in evolutionary biology. We examined mandible and leg shape in nearly 100 Amazonian termite species using geometric morphometrics and phylogenetic comparative methods. This approach allowed us to assess how feeding ecology and centroid size of body parts contribute to shape variation while accounting for shared evolutionary history across species. We show that mandible shape varies with feeding ecology along a wood-to-soil (humification) gradient, with wood-feeding species exhibiting shorter, more robust mandibles and soil-feeding species showing more elongated forms with a prominent apical tooth. In contrast, leg shape is best explained by leg centroid size and shows limited differentiation across feeding groups. Evolutionary model comparisons indicate that mandible shape is consistent with models suggesting multiple evolutionary optima associated with feeding habit, whereas leg shape is better described by a single optimum. Together, our results indicate that mandible and leg morphology vary along complementary axes: mandibles reflect dietary variation, while legs predominantly scale with size. This illustrates how different processes govern morphological variation in a dominant tropical termite radiation.

Large-scale patterns of species richness have been attributed to ecological limits, variation in diversification rates, and differences in evolutionary time, yet the relative importance of these drivers remains debated. Here, we present a unifying framework distinguishing four richness-generating scenarios, defined by contrasting roles of evolutionary time and speciation rates, which yields explicit and testable predictions for how evolutionary time, speciation, and environmental factors influence species richness. We applied this framework by analyzing 129 distinct, nonoverlapping clades spanning amphibians, reptiles, birds, and mammals. For each clade, we integrated historical biogeographic reconstructions, multiple estimates of speciation rates, and GIS-based environmental data. Using structural equation modeling, we quantified the direct and indirect effects of evolutionary time, speciation rates, and environmental conditions (productivity, temperature, and precipitation) on species richness. We further tested whether these effects varied systematically with clade-level traits, including age, physiology, diversity, and geographic extent. Productivity emerged as the dominant predictor of species richness, exerting strong and consistent direct effects that were largely invariant to clade traits. In contrast, speciation rates contributed little to species richness, while the influence of evolutionary time was highly context-dependent and most pronounced in younger clades. Temperature showed consistent direct effects not mediated by productivity, evolutionary time, or speciation rates, whereas precipitation influenced richness primarily via productivity. Together, our results support a productivity-driven equilibrium view of species richness, in which diversity reflects a balance between speciation and extinction regulated by energy availability. Deviations from equilibrium dynamics, particularly in younger clades, highlight the role of evolutionary history on biodiversity gradients.

Aim: To determine how species richness gradients—commonly considered universal—vary across the phylogenetic hierarchy of birds and mammals, and to uncover how clade age and size predetermine the gradients. Location: Global. Time Period: Last 120 million years. Taxa Studied: Birds and mammals (~15,000 species). Methods: We used large‐scale phylogenies of birds and mammals and captured the species richness gradient for each of their monophyletic clades. Gradient strength was quantified with respect to latitude, environmental productivity and temperature using multiple measures (raw slopes, log transformation, log–log transformation, and correlations). To distinguish statistical from biological effects, we compared the observed gradients to those generated by null models that randomly reassigned species to clades while preserving the phylogeny and species distributions. Results: Species richness gradients show considerable variation. Small and young clades exhibited inconsistent gradients—including reverse or flat gradients—while older and larger clades converged on steep, consistent gradients. Even moderately large clades (~500 species) commonly displayed reverse gradients. Null models replicated this trend but only partially, implying that biological effects also drive gradient variation. These phylogenetic trends were sensitive to the choice of gradient measure: raw slopes frequently inflated the strength of this trend and the apparent differences among clades, while log and log–log transformations revealed only moderate trends. Main Conclusions: Species richness gradients are not universal, nor are they phylogenetic scale‐invariant. Instead, they follow systematic trends across the phylogenetic hierarchy. Young, small clades often bear signatures of their region of origin and historical dispersal, whereas older, larger clades converge on similar gradients. Recognising the variation and the phylogenetic trends within it elucidates the formation of biodiversity patterns. We offer guidelines for choosing gradient measures, arguing that multiple metrics, combined with careful use of null models, are necessary for a nuanced understanding of how, and why, global biodiversity patterns diverge from the presumed universal gradients.

Aim: To evaluate the extent to which dorsal body colouration in lagomorphs follows ecogeographical patterns, particularly Gloger's rule, by assessing the relative influence of climate, forest vertical structure, and phylogenetic relatedness on eumelanin‐ and pheomelanin‐based pigmentation. Location: Global. Time Period: Contemporary. Major Taxa Studied: Lagomorpha (families Leporidae and Ochotonidae). Methods: We extracted dorsal colouration data for 83 lagomorph species, quantifying eumelanin (darkness) and pheomelanin (redness). Using Bayesian phylogenetic regressions, we tested the effects of climate, forest vertical structure, and phylogenetic relatedness on colouration patterns across all species and within each family. Results: Dorsal darkness was strongly associated with precipitation, supporting a moisture‐based interpretation of Gloger's rule. Redness was related to precipitation, UV‐B radiation, and forest vertical structure, suggesting that multiple environmental factors drive pheomelanin‐based pigmentation. In Leporidae, darker pelage was particularly linked to precipitation, reflecting the importance of environmental pressures. In contrast, Ochotonidae exhibited little environmental influence on colouration, with phylogenetic relatedness being the dominant predictor. Main Conclusions: Our findings reveal divergent patterns between leporids and ochotonids, reflecting distinct ecological and evolutionary histories. Precipitation emerges as a primary driver of eumelanin‐based pigmentation, especially in Leporidae, while Ochotonidae shows greater phylogenetic conservatism. Pheomelanin‐based pigmentation, however, exhibits weaker and more context‐dependent effects, underscoring the need to consider multiple environmental factors. These results refine our understanding of Gloger's rule and highlight the importance of clade‐specific approaches in macroecological analyses of trait evolution.

Aim: Animal coloration varies in response to environmental conditions. One well‐known principle, Gloger's rule, suggests that warmer and wetter environments lead to more pigmented animals. Yet, the original formulation lacks differentiation between the two primary melanin pigments: eumelanin and pheomelanin. We examined spatial eumelanin and pheomelanin variation to unravel the impact of various ecological factors on pigment deposition, and to assess support for the complex version of Gloger's rule.Location: South America.Time Period: Contemporary.Major Taxa Studied: Sigmodontine rodents.Methods: We extracted pelage color data from 231 species and quantified the geographic variation in eu‐ and pheomelanin deposition. We performed linear multiple regression to investigate the influence of temperature, precipitation, predator diversity, and UVA‐B radiance in eumelanin (lightness) and pheomelanin (redness).Results: Our findings support the original formulations of Gloger's rule. Rodents in warmer and rainier regions, which also entails greater exposure to UV radiation and a diverse range of predators, exhibit darker‐colored pelage. In addition, redder rodents prevail in warmer environments. However, contrary to the rule predictions, we observe a reversal for reddish patterns in relation to precipitation, with rainier regions showcasing more intense red rodents.Main Conclusions: Our study breaks new ground by investigating previously unexplored facets of Gloger's rule in a continental mammalian group. We discovered compelling evidence that darker and redder coloration aligns closely with temperature and rainfall gradients. Although we found support for eumelanin–pelage predictions, expectations for pheomelanin pigmentation were only partially met. Our results might suggest that selective pressures act differently on dark and reddish coloration, revealing that coloration patterns in response to climate are more intricate than previously formulated.

Speciation rates vary greatly among taxa and regions and are shaped by both biotic and abiotic factors. However, the relative importance and interactions of these factors are not well understood. Here we investigate the potential drivers of speciation rates in South American freshwater fishes, the most diverse continental vertebrate fauna, by examining the roles of multiple biotic and abiotic factors. We integrate a dataset on species geographic distribution, phylogenetic, morphological, climatic, and habitat data. We find that Late Neogene-Quaternary speciation events are strongly associated with body-size evolution, particularly in lineages with small body sizes that inhabit higher elevations near the continental periphery. Conversely, the effects of temperature, area, and diversity-dependence, often thought to facilitate speciation, are negligible. By evaluating multiple factors simultaneously, we demonstrate that habitat characteristics associated with elevation, as well as body size evolution, correlate with rapid speciation in South American freshwater fishes. Our study emphasizes the importance of integrative approaches that consider the interplay of biotic and abiotic factors in generating macroecological patterns of species diversity.

Fish farming is commonplace worldwide, especially in Asian countries. World aquatic animals’ production was approximately 178 million tons in 2020, and from this total, around 89% was destined for human consumption (FAO, 2022 Food and Agriculture Organization of the United Nations – FAO, 2022. The state of world fisheries and aquaculture [online]. Rome. Retrieved in 2023, March 20, from https://www.fao.org/3/cc0461en/online/cc0461en.html https://www.fao.org/3/cc0461en/online/cc... ). The demand for animal protein increases the consumption of fish and its derivatives, and therefore reflects on the increase in fish farming (El-Hack et al., 2022 El-Hack, M.E.A., El-Saadony, M.T., Nader, M.M., Salem, H.M., El-Tahan, A.M., Soliman, S.M., & Khafaga, A.F., 2022. Effect of environmental factors on growth performance of Nile tilapia (Oreochromis niloticus). Int. J. Biometeorol. 66(11), 2183-2194. PMid:36044083. http://dx.doi.org/10.1007/s00484-022-02347-6. http://dx.doi.org/10.1007/s00484-022-023... ). In Brazil, this activity has been developing at a fast rate, mainly due to the demand of the domestic consumer market (Embrapa, 2020 Empresa Brasileira de Pesquisa Agropecuária – Embrapa, 2020. O mercado de peixes da piscicultura no Brasil: estudo do segmento de supermercados. Palmas: Embrapa Pesca e Aquicultura, 38 p., Boletim de Pesquisa e Desenvolvimento, no. 25. ). Nile tilapia (Oreochromis niloticus) is the most cultivated species in Brazil (IBGE, 2019 Instituto Brasileiro de Geografia e Estatística – IBGE, 2019. Pecuária. Retrieved in 2021, March 20, from https://cidades.ibge.gov.br/brasil/pesquisa/18/16459?ano=2019 https://cidades.ibge.gov.br/brasil/pesqu... ), and widely used in aquaculture worldwide (FAO, 2023 Food and Agriculture Organization of the United Nations – FAO, 2023. Oreochromis niloticus [online]. Rome: Fisheries and Aquaculture. Retrieved in 2023, March 20, from https://www.fao.org/fishery/en/introsp/3399/en https://www.fao.org/fishery/en/introsp/3... ).

There are strong physiological and behavioral differences that allow animals to live in forests versus savannas. For example, terrestrial forest‐dwelling mammals tend to be small compared to species living in savannas. Robust capuchin monkeys (genus Sapajus) are widespread in tropical South America, occurring in both forest and savanna environments, with forest species considered basal in an evolutionary context. Whether or not skull shape and size variations are associated with variation in resource use remains unknown, particularly for the two species living in savanna (Sapajus libidinosus and S. cay). Here we show that savanna species present convergent size and skull characteristics that may facilitate living in this new environment. Geometric morphometric methods were used to assess skull size and shape variation for 184 Sapajus specimens distributed across South America. We used phylogenetic generalized least squares to test size against environmental variables and multivariate morphological trajectories/partial least square analyses on the skull shape to detect shape differences in specimens between forest and savanna biomes. Our findings reveal Sapajus size reduction in the evolutionary transition from forest to savanna, a process related to increasing seasonality. Moreover, we found morphological parallelism in the skull (e.g., muzzle shortening) and (large) molars in the two savanna species, features that may facilitate the processing of harder food such as fallback resources. We associate these phenotypic differences to the evolutionary process of colonizing the savannas by primates (including early hominins), leading to morphological adaptations to tolerate stressful, seasonal environments, such as body size reduction and ingestion and mastication of tough foods.