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Natural history museums are vital repositories of specimens, samples and data that inform about the natural world; this Formal Comment revisits a Perspective that advocated for the adoption of compassionate collection practices, querying whether it will ever be possible to completely do away with whole animal specimen collection.

Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexual dichromatism in this radiation and examine whether the presence of dichromatism is associated with increased rates of net diversification. We find that sexual dichromatism evolved once within hyperoliids and was followed by numerous independent reversals to monochromatism. We detect significant diversification rate heterogeneity in Afrobatrachia and find that sexually dichromatic lineages have double the average net diversification rate of monochromatic lineages. By conducting trait simulations on our empirical phylogeny, we demonstrate that our inference of trait-dependent diversification is robust. Although sexual dichromatism in hyperoliid frogs is linked to their rapid diversification and supports macroevolutionary predictions of speciation by sexual selection, the function of dichromatism in reed frogs remains unclear. We propose that reed frogs are a compelling system for studying the roles of natural and sexual selection on the evolution of sexual dichromatism across micro- and macroevolutionary timescales.

GrayiaGünther 1858 is a genus of relatively large (1.2–2.5 m) aquatic Afrotropical snakes. Recent molecular phylogenies recovered Grayia in its own distinct subfamily (Grayiinae), which was supported as the sister group to Colubrinae. Tropical African snakes are generally understudied, so the relationships within Grayia are poorly known. High degrees of intra- and interspecies variation can make identification difficult, and previous studies involving Grayia included misidentified specimens in other genera. The goal of this study is to create a phylogenetic tree that can be used to understand the relationships and taxonomy of Grayia via an integrative taxonomic approach that combines molecular data for 60 specimens and morphological data for 719 specimens. Two nuclear (BDNF, NT3) and four mitochondrial genes (COI, cyt b, 16S, and ND4) were used to construct phylogenetic trees with Maximum Likelihood and Bayesian Inference algorithms. The phylogenetic trees recovered two clades, Grayia caesar + G. tholloni and G. ornata + G. smythii, which the time-calibrated Bayesian Evolutionary Analysis Sampling Tree (BEAST) analysis estimated to have diverged from each other in the mid-Oligocene. This deep divergence, combined with distinct morphological differences, led us to resurrect the name XenurophisGünther 1863 as a subgenus [G. (Xenurophis) caesar, G. (Xenurophis) tholloni]. Molecular and morphological evidence further supports a new cryptic species of Grayia from the Upper and Middle Congo River and its tributaries. This new species is estimated to have diverged from its nearest sister species, G. ornata, in the Late Miocene—which coincides with the divergence dates of sister taxa within other Central African snake genera. Grayia ornata sensu stricto was found to consist of several evolutionary lineages, which mirror the patterns recovered in other Central African vertebrates. [ABSTRACT FROM AUTHOR]

Sex chromosomes of some closely related species are not homologous, and sex chromosome turnover is often attributed to mechanisms that involve linkage to or recombination arrest around sex-determining loci. We examined sex chromosome turnover and recombination landscapes in African clawed frogs (genus Xenopus) with reduced representation genome sequences from 929 individuals from 19 species. We recovered extensive variation in sex chromosomes, including at least eight nonhomologous sex-associated regions—five newly reported here, with most maintaining female heterogamety, but two independent origins of Y chromosomes. Seven of these regions are found in allopolyploid species in the subgenus Xenopus , and all of these reside in one of their two subgenomes, which highlights functional asymmetry between subgenomes. In three species with chromosome-scale genome assemblies (Xenopus borealis , Xenopus laevis , and Xenopus tropicalis), sex-specific recombination landscapes have similar patterns of sex differences in rates and locations of recombination. Across these Xenopus species, sex-associated regions are significantly nearer chromosome ends than expected by chance, even though this is where the ancestral recombination rate is highest in both sexes before the regions became sex associated. As well, expansions of sex-associated recombination arrest occurred multiple times. New information on sex linkage along with among-species variation in female specificity of the sex-determining gene dm-w argues against a "jumping gene" model, where dm-w moves around the genome. The diversity of sex chromosomes in Xenopus raises questions about the roles of natural and sexual selection, polyploidy, the recombination landscape, and neutral processes in driving sex chromosome turnover in animal groups with mostly heterogametic females. [ABSTRACT FROM AUTHOR]

Lygodactylus is the most speciose gekkonid group in Africa, with several additional, candidate species already identified from previous studies. However, in mainland Africa, several groups remain only partially resolved, and there are several taxonomic inconsistencies. Lygodactylus gutturalis was described from Guinea-Bissau in the 1870s and since then, the species has been recorded from West to East Africa, and it is widely distributed through different biomes and ecoregions. However, this taxon has never been studied in detail. In this work, we use an integrative approach, including molecular phylogenetic analysis, morphometrics, skull osteology, and biogeography to provide the first systematic revision of the L. gutturalis species complex. The L. gutturalis complex is a subgroup within the L. picturatus group and includes nine well-differentiated species. We elevate Lygodactylus gutturalis dysmicus to full species status, recognize Lygodactylus depressus as the sister species to L. gutturalis , describe five new species (Lygodactylus kibera sp. nov. , Lygodactylus karamoja sp. nov. , Lygodactylus mirabundus sp. nov. , Lygodactylus leopardinus sp. nov. and Lygodactylus gamblei sp. nov.), and propose an additional candidate species that requires further research. Also, in order to shed light on some taxonomic inconsistencies between the L. gutturalis and Lygodactylus angularis groups, we revisit the L. angularis group, within which we elevate Lygodactylus angularis heeneni and Lygodactylus angularis paurospilus to full species status. The L. gutturalis subgroup diversified during the Late Miocene (between 5–15 Mya), probably as a consequence of multiple vicariant events driven by the expansion of the African savannahs and the establishment of climatic refugia. [ABSTRACT FROM AUTHOR]

Abstract: Recent years have seen an explosion in FRAND litigation, in which parties commit to license intellectual property under "fair, reasonable and non-discriminatory" (FRAND) terms, but they cannot agree on [...]