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Snakebite envenoming is a set of intoxication diseases that disproportionately affect people of poor socioeconomic backgrounds in tropical countries. As it is highly dependent on the environment its burden is expected to shift spatially with global anthropogenic environmental (climate, land use) and demographic change. The mechanisms underlying the changes to snakebite epidemiology are related to factors of snakes and humans. The distribution and abundance of snakes are expected to change with global warming via their thermal tolerance, while rainfall may affect the timing of key activities like feeding and reproduction. Human population growth is the primary cause of land-use change, which may impact snakes at smaller spatial scales than climate via habitat and biodiversity loss (e.g. prey availability). Human populations, on the other hand, could experience novel patterns and morbidity of snakebite envenoming, both as a result of snake responses to environmental change and due to the development of agricultural adaptations to climate change, socioeconomic and cultural changes, development and availability of better antivenoms, personal protective equipment, and mechanization of agriculture that mediate risk of encounters with snakes and their outcomes. The likely global effects of environmental and demographic change are thus context-dependent and could encompass both increasing and or snakebite burden (incidence, number of cases or morbidity), exposing new populations to snakes in temperate areas due to “tropicalization”, or by land use change-induced snake biodiversity loss, respectively. Tackling global change requires drastic measures to ensure large-scale ecosystem functionality. However, as ecosystems represent the main source of venomous snakes their conservation should be accompanied by comprehensive public health campaigns. The challenges associated with the joint efforts of biodiversity conservation and public health professionals should be considered in the global sustainability agenda in a wider context that applies to neglected tropical and zoonotic and emerging diseases., Graphical abstract Image 1, Highlights • Distribution and abundance of snakes are expected to be affected by climate change. • Land-use change may also impact snakes but at smaller spatial scales than climate. • Human populations could experience novel patterns and morbidity of snakebite. • Reducing snakebite should be accompanied by actions that protect snake diversity.

Snakebite causes more than 1.8 million envenoming cases annually and is a major cause of death in the tropics especially for poor farmers. While both social and ecological factors influence the chance encounter between snakes and people, the spatio-temporal processes underlying snakebites remain poorly explored. Previous research has focused on statistical correlates between snakebites and ecological, sociological, or environmental factors, but the human and snake behavioral patterns that drive the spatio-temporal process have not yet been integrated into a single model. Here we use a bottom-up simulation approach using agent-based modelling (ABM) parameterized with datasets from Sri Lanka, a snakebite hotspot, to characterise the mechanisms of snakebite and identify risk factors. Spatio-temporal dynamics of snakebite risks are examined through the model incorporating six snake species and three farmer types (rice, tea, and rubber). We find that snakebites are mainly climatically driven, but the risks also depend on farmer types due to working schedules as well as species present in landscapes. Snake species are differentiated by both distribution and by habitat preference, and farmers are differentiated by working patterns that are climatically driven, and the combination of these factors leads to unique encounter rates for different landcover types as well as locations. Validation using epidemiological studies demonstrated that our model can explain observed patterns, including temporal patterns of snakebite incidence, and relative contribution of bites by each snake species. Our predictions can be used to generate hypotheses and inform future studies and decision makers. Additionally, our model is transferable to other locations with high snakebite burden as well., Author summary Snakebite is a neglected tropical disease affecting millions, and a major cause of death of agricultural workers in the tropics. In this research, the authors have developed a simulation model that includes data for agricultural activity across the days and seasons, as well as snake behavioral patterns, and the times and locations humans and snakes meet. Using this model, they predicted observed seasonal snakebite patterns in Sri Lanka, and they successfully showed how these patterns vary between different agricultural activities, including seasonal rice cultivation, and rubber and tea harvests. The findings arising from this study demonstrate that different combinations of human and snake activity, including species and farming practice differences, are likely to generate differences in snakebite patterns across locations. This model could be applied to analyze and predict snakebite in tropical regions around the globe to help mitigate the problem.

The tropical ascidian Herdmania momus (Savigny 1816) has been rapidly expanding its distribution in the Eastern Mediterranean Basin. To examine the role of temperature resilience on its invasion success, we conducted monthly field surveys for two years at Achziv (Israel) Marine Protected Area, and examined the survival of adult individuals from native (Red Sea) and invasive (Mediterranean) populations under different temperature treatments. In addition, temperature effects on fertilization and larval development were examined in controlled laboratory conditions. Results indicate that temperature has a significant effect on H. momus from its early life stages through adulthood. Field surveys revealed a significant decline in H. momus abundance in the Mediterranean with the decrease in seawater temperature. Low temperature inhibited development of early life stages, and individuals from both populations demonstrated low survivability under low temperature treatment. All the above may be derived from the tropical origin of H. momus, and may further limit its dispersal into colder areas. However, adult individuals from the invasive population demonstrated significantly higher survivability to the high temperature treatment in comparison to the native population from the Red Sea. Larvae development, metamorphosis and settlement were enhanced and with higher rates of success under the high temperature conditions. The high-temperature adaptation of the Mediterranean population of H. momus from fertilization to adulthood may thus contribute to its expanding distribution in the Eastern Mediterranean.

The observed amplitude of the rotational photometric modulation of a star with spots should depend on the inclination of its rotational axis relative to our line of sight. Therefore, the distribution of observed rotational amplitudes of a large sample of stars depends on the distribution of their projected axes of rotation. Thus, comparison of the stellar rotational amplitudes of the Kepler KOIs with those of Kepler single stars can provide a measure to indirectly infer the properties of the spin-orbit obliquity of Kepler planets. We apply this technique to the large samples of 993 KOIs and 33,614 single Kepler stars in temperature range of 3500-6500 K. We find with high significance that the amplitudes of cool KOIs are larger, on the order of 10%, than those of the single stars. In contrast, the amplitudes of hot KOIs are systematically lower. After correcting for an observational bias, we estimate that the amplitudes of the hot KOIs are smaller than the single stars by about the same factor of 10%. The border line between the relatively larger and smaller amplitudes, relative to the amplitudes of the single stars, occurs at about 6000K. Our results suggest that the cool stars have their planets aligned with their stellar rotation, while the planets around hot stars have large obliquities, consistent with the findings of Winn et al. (2010) and Albrecht et al. (2012). We show that the low obliquity of the planets around cool stars extends up to at least 50 days, a feature that is not expected in the framework of a model that assumes the low obliquity is due to planet-star tidal realignment., ApJ, in press