1. In Chap 1 the beast of "the fields and all the birds of the air" had been made before the creation of the human couple. Here in v19 the story of their creation follows from God having merely planted the Garden and no animals have yet been mentioned. The Hebrew verb is an imperfective, suggesting that it is at this point that God made the animals. By translating the verb as a pluperfect Here the NIV and the ESV, in translating the initial verb "had formed," are attempting to harmonize the differences between Chaps 2-3 with Chap 1. A more precise translation is that found in the other versions as "the Lord God formed" (e.g., NASB, NKJ, NRS, RSV, KJV).
2. The suggestion by James McKeown (Genesis, 34) that the "parade of the animals before the human would highlight their dual sexuality—male and female—and thereby accentuate the loneliness of the human being" is interesting but lacks support from the text. The same can be said of Nahum Sarna's opinion that "by observing the otherwise universal complementary pairing of male and female, he [the man] becomes aware of his own exceptional status and of his solitariness" (Genesis, 22). Nowhere is it reflected in the text that Adam was even aware of his own solitariness, nor does the text hint in any way of the animals coming before Adam in pairs of male and female.