And out of the ground the LORD God formed every beast of the field, and every fowl of the air; and brought them unto Adam to see what he would call them: and whatsoever Adam called every living creature, that was the name thereof. And Adam gave names to all cattle, and to the fowl of the air, and to every beast of the field; but for Adam there was not found an help meet for him. Genesis 2:19-20
So how many species did Adam name?
Well, if you believe the Genesis story, "every living creature" was directly and immediately created by God in that failed matchmaking attempt. God hoped that one of them (the bot fly maybe) would strike Adam's fancy, but none of them did. Shucks! So God created Eve instead.
In the process, though, Adam named all of the species that God created. And he did it in a single afternoon.
So why is it taking us so long? Thousands of biologists have been working for for nearly 350 years, yet they still haven't named them all.
About ten days ago, the Integrated Taxonomic Information System (ITIS) recorded its millionth species. But that leaves another 750,000 known species that have yet to be included. And no one knows (except maybe Adam and God) how many unknown species are still out there. Some estimates put it at as many as ten million or so (not including extinct species).
So Adam must have identified and named millions of species on that fine afternoon in the garden of Eden. 350,000 species of beetles, 120,000 flies, 100,000 parasitic wasps, 20,000 nematodes. And he was just getting started. He must have needed that nap after he was done. (I sympathize with Adam. I spent a few hours this afternoon trying to identify a half dozen aquatic invertebrates.)
But it was all part of God's plan. He was trying to find a mate for Adam and he just got carried away with beetles, flies, wasps, and worms. Stuff like that happens in the Bible.