In response to schrafinator:
All the food they would need for water is rain water (they probably had enough). Actually they would need enough food for 2 horses. Yes this is a lot but, they had enough room to store a lot of food. Here are some figures to back up this claim.
http://www.answersingenesis.org/...answersbook/arksize13.asp
In response to nwr:
Actually 8 people is not that bad as many animals, such as the grazers, did not have to be fed every day. i.e. they were likely given enough food at a time to last 2 or more days. As for the Aussie animals, I think that God has a sense of humor and directed animals to different places, Austrailia being his "oddity" place.
In response to Ringo:
I mean kinds as in equines, canines, bears, etc.
And Dinos did not have to be sexually mature. Who said that they all got off the ark and immediately began reproducing. I believe they migrated a ways before mating. And Dinos did not go extinct immediately after the flood. In fact "dragons" fit the criteria for dinosaurs very well minus the firebreathing part. The fact that so many different cultures have such similiar depictions of these beasts lends much credibility to their existance. The Bible even depicts a creature the sounds like one of the sauropods. (Job 40:15-24)
And you are correct that the number is larger than 40, but its actually 150 (Genesis 7:24). Still a reasonable number.