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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Squint on head turn in a Snowy Owl (Bubo scandiacus). (a) Pre-blink; (b) Both lids start to come together, the pupil remaining visible; (c) A small gap remains between the lids.