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In biodiversity research, the retrieval of genetic material from organisms is a common and essential component for assessing genetic diversity. The welfare of the organism, however, needs to be balanced against the overall goal of the intended research. One sampling technique often applied to retrieve DNA material from small reptiles is the removal of a small portion of the distal end of the tail. While most squamate reptiles have tail autotomy, some species (e.g. many iguanid lizards and snakes) do not regenerate tail tissue. We therefore explored the efficacy of a minimally disruptive technique, buccal swabbing, as an alternative to tissue sampling via tail clipping, particularly for species without tail autotomy, using dwarf chameleons (Bradypodion spp.) as a case study. The two sampling techniques were compared to assess the efficacy of DNA retrieval. We also evaluated the financial implications of each technique. The results indicate that buccal swabs paired with a specialised DNA extraction kit offer a feasible (although expensive), once-off alternative to tissue sampling, but with no material left for biobanking. Deviations in swab type used and the DNA extraction process (i.e. using more affordable extraction procedures) resulted in poor DNA retrieval and unreadable sequences. This finding suggests that buccal swabbing can be a suitable alternative when finances are not constrained, an expensive extraction kit is available, and biobanking is not a concern. For researchers from low- to middle-income economies, this expensive alternative may hamper research progress by placing a financial obstacle in the way, and therefore the next best option is tissue sampling. Significance: This study provides guidance on the efficacy of buccal swabs as a viable alternative to tissue samples collected via tail clipping for DNA retrieval from small reptiles. The results indicate that swabs may be a feasible alternative to tissue samples when finances are not constrained. Deviations in buccal swabbing method (i.e. using more cost-effective alternatives) performed poorly in DNA retrieval and do not offer competitive alternatives to tissue samples. Although buccal swabs were shown to offer an alternative to tissue samples, the financial implications to research in low- to middle-income economies may hinder research goals unnecessarily.

A horizon scan was conducted to identify emerging and intensifying issues for biodiversity conservation in South Africa over the next 5–10 years. South African biodiversity experts submitted 63 issues of which ten were identified as priorities using the Delphi method. These priority issues were then plotted along axes of social agreement and scientific certainty, to ascertain whether issues might be “simple” (amenable to solutions from science alone), “complicated” (socially agreed upon but technically complicated), “complex” (scientifically challenging and significant levels of social disagreement) or “chaotic” (high social disagreement and highly scientifically challenging). Only three of the issues were likely to be resolved by improved science alone, while the remainder require engagement with social, economic and political factors. Fortunately, none of the issues were considered chaotic. Nevertheless, strategic communication, education and engagement with the populace and policy makers were considered vital for addressing emerging issues.

Differing ecological conditions are considered drivers of directional selection among or between populations, resulting in ecological speciation. In particular, divergence of phenotypes in differing habitats, or convergence of phenotypes in similar habitats, can be the result of directional selection. Accordingly, species of dwarf chameleons ( Bradypodion ) that occur in structurally similar habitats tend to converge on a similar phenotype. Conversely, dwarf chameleons from contrasting habitats have been shown to diverge in phenotype. Thus, ecological speciation appears to be a mechanism for diversification in this genus. Using a combination of morphological (functional and ornamental traits) and population genetic analyses (microsatellite loci), we examined whether three closely related Bradypodion lineages have diverged for these dimensions. We assess whether habitats differ in structure for features related to divergence in morphological traits or whether convergence of traits corresponds to similarity in habitat structure. We find that the three taxa differ significantly at a population genetic level, but some allele sharing suggests incomplete lineage sorting or gene flow. Differences among taxa for functional traits related to gripping of branches (e.g., distal limb size [hands/feet]) can be explained by the perch diameters used by chameleons, whereas the degree of ornamentation differs among taxa in different habitats but is convergent for those in similar habitats. These outcomes are congruent with an ecological model of speciation, with taxa having diverged genetically but showing phenotypic convergence when in similar habitats and divergence when in different habitats.

The Kunming-Montreal Global Biodiversity Framework recognises the global importance of genetic diversity conservation.Additions to the biotechnological toolbox have expanded the scope and potential of biodiversity research.Biotechnological methods face ethical concerns despite their potential for advancing conservation genomics.Addressing existing inequities is essential for leveraging genomics in biodiversity-rich developing regions that host the majority of biodiversity. The Kunming-Montreal Global Biodiversity Framework marks a significant step toward conserving genetic diversity on a global scale. Sequencing advancements have broadened biodiversity studies by enabling the mapping of species distributions, increasing understanding of ecological interactions, and monitoring genetic diversity. However, these tools are hindered by inequalities and biases, particularly in biodiversity-rich developing countries. To navigate these challenges, we propose strategies using the existing biotechnological toolbox to make biodiversity data more accessible and useful for research and development. This includes increasing funding for database curation, improving metadata standards, addressing inequalities in technological capacity, and supporting holistic capacity-building programmes. Implementing these strategies can unlock new opportunities for biodiversity research aligned with sustainable development principles and can contribute to improved conservation outcomes. The Kunming-Montreal Global Biodiversity Framework marks a significant step toward conserving genetic diversity on a global scale. Sequencing advancements have broadened biodiversity studies by enabling the mapping of species distributions, increasing understanding of ecological interactions, and monitoring genetic diversity. However, these tools are hindered by inequalities and biases, particularly in biodiversity-rich developing countries. To navigate these challenges, we propose strategies using the existing biotechnological toolbox to make biodiversity data more accessible and useful for research and development. This includes increasing funding for database curation, improving metadata standards, addressing inequalities in technological capacity, and supporting holistic capacity-building programmes. Implementing these strategies can unlock new opportunities for biodiversity research aligned with sustainable development principles and can contribute to improved conservation outcomes.

Phenotypic performance in different environments is central to understanding the evolutionary and ecological processes that drive adaptive divergence and, ultimately, speciation. Because habitat structure can affect an animal's foraging behaviour, anti-predator defences, and communication behaviour, it can influence both natural and sexual selection pressures. These selective pressures, in turn, act upon morphological traits to maximize an animal's performance. For performance traits involved in both social and ecological activities, such as bite force, natural and sexual selection often interact in complex ways, providing an opportunity to understand the adaptive significance of morphological variation with respect to habitat. Dwarf chameleons within the Bradypodion melanocephalum-Bradypodion thamnobates species complex have multiple phenotypic forms, each with a specific head morphology that could reflect its use of either open- or closed-canopy habitats. To determine whether these morphological differences represent adaptations to their habitats, we tested for differences in both absolute and relative bite performance. Only absolute differences were found between forms, with the closed-canopy forms biting harder than their open-canopy counterparts. In contrast, sexual dimorphism was found for both absolute and relative bite force, but the relative differences were limited to the closed-canopy forms. These results indicate that both natural and sexual selection are acting within both habitat types, but to varying degrees. Sexual selection seems to be the predominant force within the closed-canopy habitats, which are more protected from aerial predators, enabling chameleons to invest more in ornamentation for communication. In contrast, natural selection is likely to be the predominant force in the open-canopy habitats, inhibiting the development of conspicuous secondary sexual characteristics and, ultimately, enforcing their overall diminutive body size and constraining performance.

Yeasts have been used to manage a large number of plant diseases, but little is known about the mechanisms used by these biocontrol agents. The objectives of the present study were to evaluate the antagonistic effect of yeasts against Rhizoctonia solani and possible mechanisms of action in cowpea plants. Seventy yeast isolates were obtained from leaf, root and stem tissues of cowpea and common bean plants. Screening experiments were conducted in a greenhouse at temperatures ranging from 15 to 26 °C in the first and from 22 to 31 °C in the second experiment. Candida saopaulonensis C6A, Cryptococcus laurentii FVC10 and Bullera sinensis FVF10 (R1) reduced disease severity by 57.4%, 48.5% and 66.3%, respectively. Cowpea plants treated with FVF10 (R1) showed the highest peroxidase and catalase activities. The mechanisms of action were based on competition and induction of enzymes such as peroxidase, catalase and ascorbate peroxidase in cowpea. Candida saopaulonensis C6A, C. laurentii FVC10 and B. sinensis FVF10 (R1) are potential biocontrol agents of damping-off and stem rot caused by R. solani on cowpea plants.

Genetic diversity provides the capacity for species to evolve in response to environmental change, and its importance in assessing the status of species is well established. However, there is a paucity of genetic monitoring studies. The Endangered western leopard toad (Sclerophrys pantherina), endemic to South Africa, is a good candidate for genetic monitoring, due to its restricted distribution consisting of two disjunct populations (within the City of Cape Town (CoCT) and the Overstrand), with the CoCT population having experienced more drastic habitat alteration due to urbanisation, and presumably a large population decline. To establish a baseline for genetic monitoring, we examined the change in genetic diversity and structure within the CoCT population across two time periods (2008 and 2018) using 12 microsatellite markers. Despite monitoring occurring over only four generations, there is evidence of increased inbreeding and a shift in the genetic structure. These changes are likely due to previous, severe impacts on the population, with 91% of natural habitat lost in the study area. There is also evidence of at least three historical bottlenecks that are likely the initial cause of inbreeding, with extreme habitat loss in the twentieth century leading to the genetic changes detected within the last decade. Although declines in allelic richness were not detected, the inbreeding and change in genetic structure can be considered early warning signs of genetic erosion, even over a short monitoring interval. This provides a baseline for future monitoring, with the ultimate goal of tracking long-term trends to guide conservation actions.

Histone modifications regulate the structural status of chromatin and thereby influence the transcriptional status of genes. These processes are controlled by the recruitment of different enzymes to a specific genomic site. Furthermore, obtaining an understanding of these mechanisms could help delineate alternative treatment and preventive strategies for cancer. For example, in gastric cancer, cholecalciferol, curcumin, resveratrol, quercetin, garcinol and sodium butyrate are natural regulators of acetylation and deacetylation enzyme activity that exert chemopreventive and anticancer effects. Here, we review the recent findings on histone acetylation in gastric cancer and discuss the effects of nutrients and bioactive compounds on histone acetylation and their potential role in the prevention and treatment of this type of cancer.

Summary The head is a complex integrated system that is implicated in many vital functions. As such, its morphology is impacted by different and sometimes conflicting demands. Consequently, head shape varies greatly depending on the environment and dietary ecology of an organism. Moreover, given its role in territory defence and mating in lizards, it is also subjected to strong sexual selection in these animals. We investigated the relationships between head shape, bite performance and diet in 14 of the 17 extant Bradypodion species to determine whether variation in diet can explain the observed diversity in bite force and head shape in this genus. We also evaluate differences between sexes in terms of the relationships between head shape, bite force and diet and predict tighter relationships in females given that the head in this sex is principally under natural selection. Our results show that there is indeed a correlation between head shape, diet and bite force, but the direction and magnitude are sex‐dependent. Whereas we observed a correlation between absolute bite force and head shape in both sexes, size‐corrected bite force was correlated with mandible and quadrate shape in females only. Despite strong correlations between bite force and prey hardness, and between prey hardness and head shape, we did not find any relationship between head shape and prey evasiveness. These data suggest that the cranial system in chameleons of the genus Bradypodion evolves under natural selection for the ability to eat large or hard prey. Moreover, significant differences in the ecomorphological relationships between the two sexes suggest that sexual selection plays a role in driving the evolution of bite force and head shape. These data suggest that ecomorphological relationships may be sex‐dependent. Lay Summary

Recent scientific evidence shows that genetic diversity must be maintained, managed, and monitored to protect biodiversity and nature's contributions to people. Three genetic diversity indicators, two of which do not require DNA‐based assessment, have been proposed for reporting to the Convention on Biological Diversity and other conservation and policy initiatives. These indicators allow an approximation of the status and trends of genetic diversity to inform policy, using existing demographic and geographic information. Application of these indicators has been initiated and here we describe ongoing efforts in calculating these indicators with examples. We specifically describe a project underway to apply these indicators in nine countries, provide example calculations, address concerns of policy makers and implementation challenges, and describe a roadmap for further development and deployment, incorporating feedback from the broader community. We also present guidance documents and data collection tools for calculating indicators. We demonstrate that Parties can successfully and cost‐effectively report these genetic diversity indicators with existing biodiversity observation data, and, in doing so, better conserve the Earth's biodiversity.