New Article: Shining new light on mammalian diving physiology using wearable near-infrared spectroscopy Dear MARMAM, We are pleased to announce the publication of our new paper in PLoS Biology: McKnight JC, Bennett KA, Bronkhorst M, Russell DJF, Balfour S, Milne R, Bivins M, Moss SEW, Colier W, Hall AJ and Thompson D (2019) Shining new light on mammalian diving physiology using wearable near-infrared spectroscopy. PLoS Biol 17(6): e3000306. https://doi.org/10.1371/journal.pbio.3000306 Abstract: Investigation of marine mammal dive-by-dive blood distribution and oxygenation has been limited by a lack of noninvasive technology for use in freely diving animals. Here, we developed a noninvasive near-infrared spectroscopy (NIRS) device to measure relative changes in blood volume and haemoglobin oxygenation continuously in the blubber and brain of voluntarily diving harbour seals. Our results show that seals routinely exhibit preparatory peripheral vasoconstriction accompanied by increased cerebral blood volume approximately 15 s before submersion. These anticipatory adjustments confirm that blood redistribution in seals is under some degree of cognitive control that precedes the mammalian dive response. Seals also routinely increase cerebral oxygenation at a consistent time during each dive, despite a lack of access to ambient air. We suggest that this frequent and reproducible reoxygenation pattern, without access to ambient air, is underpinned by previously unrecognised changes in cerebral drainage. The ability to track blood volume and oxygenation in different tissues using NIRS will facilitate a more accurate understanding of physiological plasticity in diving animals in an increasingly disturbed and exploited environment. Please feel free to e-mail me at jcm20@st-andrews.ac.uk if you have any questions. Best wishes, Chris McKnight & co-authors