Gut microbial communities are part of the regulatory array of various processes within their hosts, ranging from nutrition to pathogen control. Recent evidence shows that dung beetle's gut microbial communities release substances with antifungal activity. Because of the enormous diversity of gut microorganisms in dung beetles, there is a possibility of discovering novel compounds with antifungal properties. We tested the antifungal activity mediated by gut microbial communities of female dung beetles against nine phytopathogenic fungi strains (Colletotrichum asianum-339, C. asianum-340, C. asianum-1, C. kahawae-390, C. karstii-358, C. siamense-220, Fusarium oxysporum-ATCC338, Nectria pseudotrichia-232, Verticillium zaelandica-22). Our tests included the gut microbial communities of three species of dung beetles: Canthon cyanellus (roller beetle), Digitonthophagus gazella (burrower beetle), and Onthophagus batesi (burrower beetle), and we followed the dual confrontation protocol, i.e., we challenged each fungal strain with the microbial communities of each species of beetles in Petri dishes containing culture medium. Our results showed that gut microbial communities of the three dung beetle species exhibit antifungal activity against at least seven of the nine phytopathogenic fungal strains. The gut microbial communities of Onthophagus batesi significantly decreased the mycelial growth of the nine phytopathogenic fungi strains; the gut microbial communities of Canthon cyanellus and Digitonthophagus gazella significantly reduced the mycelial growth of seven strains. These results provide a basis for investigating novel antifungal substances within gut microbial communities of dung beetles.
Anthropogenic climate change is already causing dangerous and widespread disruptions in global ecological and social systems and affects the lives of billions of people around the world. Even with scaled-up risk management and adaptation, the limits of adaptation will often be reached. Currently, very little is known about the degree to which societies can adapt to climate change, and where and when limits to adaptation will be reached. In this paper, we conceptualize adaptation limits through a novel methodological framework, assess adaptation limits along adaptation pathways, and propose a research strategy for empirical and model-based limits assessments based on biophysical and socio-economic data. Assessing limits is central to national and international adaptation policymaking. More efficient adaptation can also help climate mitigation efforts.
As emerging methods for carbon removal and controversial proposals around solar radiation modification are gaining traction in climate assessments and policy debates, a better understanding of how the public perceives these approaches is needed. Relying on qualitative data from 44 focus groups (n = 323 respondents), triangulated with a survey conducted in 22 countries (n = over 22 000 participants), we examine the role that climate change beliefs and attitudes towards climate action play in the formation of public perceptions of methods for carbon removal and solar radiation modification. We find that nationally varying degrees of perceived personal harm from climate change and climate worry predict support for these technologies. In addition to different perceptions of the problem, varying perceptions of the solution – i.e. the scope of climate action needed − shape publics’ assessment. Various tensions manifest themselves in publics’ reflections on the potential contribution of these climate technologies to climate action, including “buying time vs. delaying action”, “treating the symptoms vs. tackling the root causes”, and “urgency to act vs. effects only in the distant future”. We find that public perceptions are embedded in three broader narratives about transformation pathways, each reflecting varying notions of responsibility: (i) behavior change-centred pathways, (ii) top-down and industry-centred pathways, and (iii) technology-centred pathways. These results suggest that support for the deployment of the climate technologies studied hinges on them being tied to credible system-wide decarbonization efforts as well as their ability to effectively respond to a variety of perceived climate impacts.
Studies of reproductive biology and resources availability to floral visitors by plant species are important to understand the plant-pollinator interactions that drive species adaptation. We aim to understand the relationship between reproduction mechanisms of Deuterocohnia meziana (Bromeliaceae) and pollinators. The species occurs in Bolivia and Paraguay, and it is the only species of the genus found in Brazil, where it is restricted to ironstone outcrops. These areas are currently threatened by the iron mining industry. Additionally, they face risks from fire occurrence and grazing by cattle. We analyzed the floral biology, reproductive system, phenology, and pollination ecology of a natural population of Deuterocohnia meziana, from ironstone outcrops in Brazil. The species exhibits diurnal anthesis, with stigma receptive throughout anthesis, and 77% of pollen viability. Deuterocohnia meziana produces relatively large amounts of nectar, especially early in the morning (32.8 ± 9.4 μl), with a mean sugar concentration of 23.5 (± 3.2) ºBrix. It is self-incompatible with a peak flowering occurring in August (dry season), although flowers are observed continuously throughout the year. The species exhibits two types of inflorescences, young and mature, among which an average of 13.1 and 3.6 flowers open per day, respectively. Hummingbirds and bees are the effective pollinators, although butterflies and ants also visit D. meziana flowers. The species is reliant on exogenous pollen and pollinators for fruit set. The continuous conservation of D. meziana populations and their communities is essential for preserving plant-pollinator mutualism and the floral community adapted to ironstone outcrops.