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Animal‐borne biologging technology allows researchers to understand the physiological responses of wild animals, especially songbirds, to environmental changes. Songbirds are of interest in studying these responses because of their visibility and relatively small body size yet high energetic demand of their various life‐history stages (e.g., molt, migration, breeding). Previous methods for monitoring responses, such as heart rate activity, have relied on surgical implantation of electrodes connected to bulky electronic devices which affect the well‐being of birds, indirectly influence bird behavior and create stress artifacts. A non‐invasive, lightweight solution is needed. This study introduces eutectogels, a long‐lasting gel made from deep eutectic solvents, combined with conductive threads and a wireless device to monitor the heart rate of house sparrows noninvasively through skin contact. In this work, heart rate and respiration rate measurements are validated on birds under anesthesia. These tests are repeated on birds that are awake but restrained. The eutectogel outperforms commercial electrodes and gels, yielding high signal‐to‐noise ratio measurements on restrained birds. The respiration rate is extracted and processed electronically from motion artifacts in the recorded signals without the need for a separate dedicated sensor. The system shows promise for future field studies on free‐living species. [ABSTRACT FROM AUTHOR]

Technologies capable of noninvasively sampling different locations in the gut upstream of the colon will enable new insights into the role of organ‐specific microbiomes on human health. Herein, an ingestible pill for the sampling of gut lumen based on one of the earliest hydraulic machines known as an Archimedes screw is reported. The design contains twisted wires as Archimedes screw driven by a motor, wirelessly activated using a magnet. The sampling performance of the screw‐pump pill is characterized using realistic in vitro models and validated in vitro using E. coli expressing different fluorescent proteins. The use of the Archimedes screw enables the pill to sample the dense GI environment. The pill is also tested ex vivo in the pig intestine and in vivo in pigs. Herein, the results show that the bacterial populations recovered from the pill's chamber closely resemble the targeted bacterial population of the microenvironment to which the pill is exposed. Such ingestible devices have the potential to revolutionize the understanding of the spatial diversity of the gut microbiome and its response to medical conditions and treatments. [ABSTRACT FROM AUTHOR]