Excrements probably was most of what they spent their time picking up and this wouldn't take very long at all seeing as how most of these animals again are very small due to their age.
Where does it say in the bible that animals were brought at a young age? Did you make this up?
Insects have no nostrils
I know I shouldn't buy into this argument, but if 'kinds' doesn't include insects, then why do we see the varieties we have today? Floating vegetation mats? Hope there are enough "floating mats" to cater to all the various environmental requirements of every 'kind' of insect we see in nature.
It's deep and getting deeper, I can see...
"My own suspicion is that the Universe is not only queerer than we suppose, but queerer than we can suppose. J.B.S Haldane 1892-1964