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Millions of years of evolution have allowed animals to develop unusual locomotion capabilities. A striking example is the legless-jumping of click beetles and trap-jaw ants, which jump more than 10 times their body length. Their delicate musculoskeletal system amplifies their muscles’ power. It is challenging to engineer insect-scale jumpers that use onboard actuators for both elastic energy storage and power amplification. Typical jumpers require a combination of at least two actuator mechanisms for elastic energy storage and jump triggering, leading to complex designs having many parts. Here, we report the new concept of dynamic buckling cascading, in which a single unidirectional actuation stroke drives an elastic beam through a sequence of energy-storing buckling modes automatically followed by spontaneous impulsive snapping at a critical triggering threshold. Integrating this cascade in a robot enables jumping with unidirectional muscles and power amplification (JUMPA). These JUMPA systems use a single lightweight mechanism for energy storage and release with a mass of 1.6 g and 2 cm length and jump up to 0.9 m, 40 times their body length. They jump repeatedly by reengaging the latch and using coiled artificial muscles to restore elastic energy. The robots reach their performance limits guided by theoretical analysis of snap-through and momentum exchange during ground collision. These jumpers reach the energy densities typical of the best macroscale jumping robots, while also matching the rapid escape times of jumping insects, thus demonstrating the path toward future applications including proximity sensing, inspection, and search and rescue. 

Biphilic surfaces having spatially distinct wetting have the potential to enable a plethora of applications ranging from fog harvesting, microfluidics, advanced manufacturing, and pumpless fluid transfer. However, complex and costly fabrication along with poor durability have hindered the widespread utilization of biphilic surfaces. Here, hierarchical biphilic micro/nanostructured surfaces passively functionalized by the atmosphere are demonstrated as a platform to create scalable and abrasion‐resistant biphilic interfaces. Biphilic hierarchical copper oxide (CuO) nanowires are fabricated on copper substrates via laser ablation followed by thermal oxidation. The surfaces spontaneously become globally superhydrophobic and locally hydrophilic due to the adsorption of airborne volatile organic compounds on the ultrahigh surface energy CuO nanowires. The curvature‐dependent spatial variation in nanowire morphology enables local roughness variation and wetting contrast without the need for selective functionalization. Coalescence‐induced droplet jumping and water vapor condensation experiments demonstrate global superhydrophobicity with discrete local hydrophilicity. In addition to enhanced fog harvesting rates, the surfaces are demonstrated to have repeatable self‐healing function with enhanced abrasion resistance compared to single‐tier structured surfaces. The work not only develops a facile method of fabricating scalable biphilic surfaces via nanoscale structure variation and atmosphere‐mediated surface modification, but also provides insights into the role of wetting contrast on droplet dynamics.