Humans DO have gills (or rather gill-like slits). But only during early developmental stage :). These structures develop eventually into the upper lip, palate and jaw during embryonic development. Couple of resources: http://www.ucmp.berkeley.edu/chordata/chordatamm.html https://evolution.berkeley.edu/evolibrary/article/evodevo_02

Thanks for asking this question. I found the following at https://biologydictionary.net/chordate/. All chordates have a pharyngeal slit. This develops into gill arches in fish. Human embryos have gillslits, but they disappear before we are born and the tissue develops into other structures in the head and neck. Generally, the tissue is modified for various purposes in terrestrial vertebrates, such as for the jaws and the Eustachian tube connecting the ear to the throat. Source: https://biologydictionary.net/chordate/