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Tropical cyclones (e.g., hurricanes and tropical storms), are considered one of the world's most destructive climatological forces, causing substantial damage especially in urban areas. However, for some arid ecosystems, tropical cyclones represent natural disturbance events, providing important sources of fresh water that support ecosystem functioning. For subsistence populations living in these regions, it is unclear whether they experience these events negatively due to the associated damages or positively within a predictable disturbance regime. Here, we assess these phenomena with traditional ranchers from Baja California Sur, Mexico, following Hurricane Kay (September 2022). We find that despite significant damage caused by the hurricane, nearly the entire sample perceived this tropical cyclone event as a net positive on their lives. This traditional ranching population has a culture that is adapted to the seasonal tropical cyclone disturbance regime, and expects extreme rain events annually to support ecosystem functioning, and therefore their economic livelihoods. To these ranchers, the climate shock is not when the hurricanes come, but rather, when hurricanes do not come. We situate our results within a disturbance ecology framework, highlighting the role of increasing aridity and probability of drought in the North American Arid West. 

Species interactions have long been predicted to increase in intensity toward the tropics and low elevations because of gradients in climate, productivity, or biodiversity. Despite their importance for understanding global ecological and evolutionary processes, plant-animal interaction gradients are particularly difficult to test systematically across large geographic gradients, and evidence from smaller, disparate studies is inconclusive. By systematically measuring postdispersal seed predation using 6995 standardized seed depots along 18 mountains in the Pacific cordillera, we found that seed predation increases by 17% from the Arctic to the Equator and by 17% from 4000 meters above sea level to sea level. Clines in total predation, likely driven by invertebrates, were consistent across treeline ecotones and within continuous forest and were better explained by climate seasonality than by productivity, biodiversity, or latitude. These results suggest that species interactions play predictably greater ecological and evolutionary roles in tropical, lowland, and other less seasonal ecosystems.