anag last edited by anag
Why early human embryo do not possess gills but possess gill slits? Please explain.
sunitasaxena last edited by
all vertebrate embryos develop “branchial clefts” (also called “pharyngeal arches” or “branchial arches”) at an early stage, and these are almost certainly the vestigial remnants of the clefts of our fishy ancestors, which develop into gills. Those branchial clefts are sometimes called “gill arches,” even in species, like reptiles, bird, and mammals, that never have gills. In humans, for example, the clefts disappear and transform into other parts of the body, including the jaw, the middle ear, and the larynx