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The genomic characteristics of adaptively radiated groups could contribute to their high species number and ecological disparity, by increasing their evolutionary potential. Here, we explored the genomic variation of Anolis lizards, focusing on three species with distinct phenotypes: A. auratus, one of the species with the longest tail; A. frenatus, one of the largest species; and A. carolinensis, one of the species that inhabits the coldest environments. We assembled and annotated two new chromosome-level reference genomes for A. auratus and A. frenatus, and compared them with the available genomes of A. carolinensis and A. sagrei. We evaluated the presence of structural rearrangements, quantified the density of repeat elements, and identified potential signatures of positive selection in coding and regulatory regions. We detected substantial rearrangements in scaffolds 1, 2 and 3 of A. frenatus different from the other species, in which the rearrangement breakpoints corresponded to hotspots of developmental genes. Further, we detected an accumulation of repeats around key developmental genes in anoles and phrynosomatid outgroups. Finally, coding sequences and regulatory regions of genes relevant to development and physiology showed variation that could be associated with the unique phenotypes of the analyzed species. Our results show examples of the hierarchical genomic variation within anoles, that could provide the substrate that promoted phenotypic disparity and contributed to their adaptive radiation. 

Abstract Methane (CH₄) is a potent greenhouse gas with a warming potential 84 times that of carbon dioxide (CO₂) over a 20‐year period. Atmospheric CH₄concentrations have been rising since the nineteenth century but the cause of large increases post‐2007 is disputed. Tropical wetlands are thought to account for ∼20% of global CH₄emissions, but African tropical wetlands are understudied and their contribution is uncertain. In this work, we use the first airborne measurements of CH₄sampled over three wetland areas in Zambia to derive emission fluxes. Three independent approaches to flux quantification from airborne measurements were used: Airborne mass balance, airborne eddy‐covariance, and an atmospheric inversion. Measured emissions (ranging from 5 to 28 mg m⁻² hr⁻¹) were found to be an order of magnitude greater than those simulated by land surface models (ranging from 0.6 to 3.9 mg m⁻²hr⁻¹), suggesting much greater emissions from tropical wetlands than currently accounted for. The prevalence of such underestimated CH₄sources may necessitate additional reductions in anthropogenic greenhouse gas emissions to keep global warming below a threshold of 2°C above preindustrial levels.