I thought this was pretty much known already. I was told in 4th grade science class (1957) that rats had large appendices and the thought was it helped them handle the wood they ingested in their day to day rattiness. I have had occasion to see a sheep’s innards, and I can testify they have quite large appendices, and I was told that vets thought it had to do with germs for digesting or processing somehow all the fibrous matter in their diet. So I’d thought this for quite some time.
You should have published!