It’s a good thing that animals aren’t susceptible to motion sickness, or that massive flooding entailing covering over all the land would cause a bit of chop, right?
As for the poo problem, well, that’s what toilets are for. I mean, duh!
But seriously, OP (because I really expect you to come back and engage in a good faith debate here and all), what about those fish? Massive global flooding of fresh water (and all that debris stuff when the land gets flooded over completely in a short time span) is not going to bode well for the fishes and stuff. As an example of this try pouring in several gallons of fresh water (and dirt and assorted crap) into your salt water fish tank then take note of what happens to the fish in there (conversely, you could do the same with your fresh water tank, to demonstrate what happens to the lakes and fresh water seas that would be flooded eventually with all that salt water stuff when some sort of equilibrium occurs…after, um, 40 days of massive flooding and…er, well, it’s hard to keep a straight face here and hard to believe that anyone who actually thinks about this can be credulous to believe this now that we know how big the earth is, and stuff about animals and plants…and geology…and meteorology…and, all that science stuff…). Er, where was I? Oh, yeah…did you try the experiment? Those things floating at the top now? Those are the dead fish. So, getting back to the fish thing, how? Did they have fish tanks on the Ark as well?
Because, you know, this would have to be a pretty big boat. Maybe the translation was wrong wrt the units of measurement. Because my back of the envelop calculation seems to indicate that the Ark would have had to be several times larger…probably an order of magnitude larger at least…to house even 2 of ever species, plus all of the stuff they would need to keep them alive for 40 days (or a year, or a parsec, or whatever), including all of the aquatic species that the original authors of the Bible didn’t know about or consider.
Or, you could just man up and say that God did it and not try and go for a rational, scientifically based explanation as to how it could have happened in reality, since, you know, it wouldn’t be believable to anyone who has even a basic understanding of the issues. Good grief, folks bought into Battleship, Pacific Rim AND Independence Day, I’d just go with the ‘God worked his magical powers to bring forth water instantly and without any actual physical effect or evidence, save all the good fish, plants and pandas, as well as a couple of people, then magically made the waters go away again without leaving any evidence and then put the good animals, plants and assorted pandas and shit right back where they came from instantaneously, while making it SEEM that other human populations outside of the Middle East had actually been all around the world during the supposed time this all happened anyway. As for dinosaurs, well, lol, they were just a trick, created by the same folks who built the glaciers, and one day a name tag will be found on one that attributes it correctly’. I think that would work better.