So that Adam could name them.
But the bigger context isn't just so that the animals could have names. God makes the beasts and brings them to Adam one by one right after the verse where God determines it isn't good for Adam to be alone. God decides to make a helper for Adam and the animals are God's first try! Adam goes through them all and it doesn't work out. In the very next verse God puts Adam to sleep and takes that infamous rib to make woman.
You can read the story in Genesis 2:18-22.
Above is a detail from a fresco in Castle Bernau, Fischlham, Austria, painted in 1995 showing the naming scene.
