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Functional and genomic studies on the differences between the gametophyte and sporophyte life phases of plants remain scarce, yet unraveling these dynamics is crucial to understanding the biology of plants and the success of each phase under different conditions. Here, we provide a reference genome for the highly invasive fernLygodium microphyllumand compare the transcriptomic and epigenomic landscapes of its gametophyte and sporophyte life phases. Under ambient conditions, we found differential regulation and splicing of developmental genes (homeobox and MADS-box clades) may play a role in the genomic determination of the haploid and diploid life stages. We generated a base pair-resolution methylome of a fern gametophyte, and determined that methylation patterns are remarkably similar between vegetative tissues despite their morphological and functional differences. We further explored the physiological and transcriptomic responses of gametophytes and sporophytes to freezing stress, the most likely abiotic factor limiting further range expansion of this invasive species. While controlled by the same genome, we show that life phases and tissues use alternative molecular pathways in response to freezing and greater physiological resilience in the gametophyte life stage to this stressor. Our results underscore the need to incorporate both life phases when developing effective mitigation strategies, as differential responses to environmental stressors between phases reveal opportunities for management approaches (e.g., targeting gametophytes in addition to sporophytes). These genomic resources fill a gap in our understanding of fundamental plant biology and inform invasive species research. 

Active systems of self-propelled agents, e.g., birds, fish, and bacteria, can organize their collective motion into myriad autonomous behaviors. Ubiquitous in nature and across length scales, such phenomena are also amenable to artificial settings, e.g., where brainless self-propelled robots orchestrate their movements into spatial-temporal patterns via the application of external cues or when confined within flexible boundaries. Like their natural counterparts, these approaches typically require many units to initiate collective motion, so controlling the ensuing dynamics is challenging. Here, we demonstrate a simple mechanism that leverages nonlinear elasticity to tame near-diffusive motile particles in forming structures capable of directed motion and other emergent behaviors. Our elasto-active system comprises two centimeter-sized self-propelled microbots connected with elastic beams. These microbots exert forces that suffice to buckle the beam and set the structure in motion. We first rationalize the physics of the interaction between the beam and the microbots. Then we use reduced-order models to predict the interactions of our elasto-active structures with boundaries, e.g., walls and constrictions, and demonstrate how they can exhibit remarkable emergent behaviors such as maze navigation. These findings demonstrate that allowing and understanding changes in body morphology can enhance the capabilities of active matter systems and enable the design of robotic materials capable of space exploration, adaptation, and complex interactions with their surrounding environment.