As an aside, my son today told me today that our appendix was used by early man to help consume raw meat. Thus, we no longer need it today.
A recent study claimed the appendix was for growing and storing good bacteria for digestion.
The reverse is true!
In our evolutionary past, the appendix was larger, and was used to digest fibrous (vegetable) material.
Recent thinking suggests that the appendix might serve as a "safe house" for beneficial bacteria that might otherwise be lost after, e.g., a severe bout of diarrhea.
Regards,