Dear colleagues, My co-authors and I are pleased to share our new paper published in eLife this week, showing that echolocating whales can detect and react to sudden prey movements during close approaches with speeds similar to ultra-fast eye-tracking responses in human vision. We conclude that this evolutionary convergence on rapid sensor-motor feedback, coupled with extreme biosonar sampling rates, has critically enabled toothed whales to target agile, energetically-valuable prey cementing their position as top-predators in aquatic niches. Our paper can be found at the following link elifesciences.org/articles/68825<http://elifesciences.org/articles/68825>. Vance, H.M., Madsen, P.T., Aguilar de Soto, N., Wisniewska, D.M., Ladegaard, M., Hooker, S.K. and Johnson, M., 2021. Echolocating toothed whales use ultra-fast echo-kinetic responses to track evasive prey. eLife, 10:e68825. https://doi.org/10.7554/eLife.68825 Abstract Visual predators rely on fast-acting optokinetic responses to track and capture agile prey. Most toothed whales, however, rely on echolocation for hunting and have converged on biosonar clicking rates reaching 500/s during prey pursuits. If echoes are processed on a click-by-click basis, as assumed, neural responses 100× faster than those in vision are required to keep pace with this information flow. Using high-resolution biologging of wild predator-prey interactions, we show that toothed whales adjust clicking rates to track prey movement within 50-200 ms of prey escape responses. Hypothesising that these stereotyped biosonar adjustments are elicited by sudden prey accelerations, we measured echo-kinetic responses from trained harbour porpoises to a moving target and found similar latencies. High biosonar sampling rates are, therefore, not supported by extreme speeds of neural processing and muscular responses. Instead, the neurokinetic response times in echolocation are similar to those of tracking responses in vision, suggesting a common neural underpinning. Feel free to contact me with any questions (hmv@st-andrews.ac.uk). Best wishes, Heather Vance ----------------------