Speaking of which...
I'm thinking about performing an experiment. I'd like to create an airtight enclosure and raise insects in it. The reason I want it air tight is because I want the atmosphere to contain around 40% oxygen. I've read that one of the reasons insects use to grow to such large size millions of years ago was due to an increased amount of oxygen in the atmosphere (around 30-35%), and it would be interesting to see if it would have any affect on the size of modern insect species to live in an oxygen rich environment. Any ideas on how to construct such a habitat?