The first occurrence.
And God said: “Let Us make man in Our image, after Our likeness; and let them have dominion over the fish of the seas, and over the winged creatures of the heavens, and over the cattle, and over all the earth, and over every creeping thing that creeps upon the earth.” Gen 1:26
The primitive root.
dalet ד = door, thus enter, move, hang
gimel ג = foot, thus foot, walk, gather
hey ה = man w/raised arms, thus look, reveal, wonder, worship, breath
The story: The back and forth (dalet) movement of the foot (gimel) which, on a fish, is his tail, propels him rapidly through the water. Fish spawn most typically by broadcasting (hey, in the sense of revealing) eggs and sperm through the water. Our English word “dog” is from this root, as his tail moves rapidly back and forth.