Large growth rings

[russian/sulcata/tortoise]

I was looking at some tort pics and i noticed some torts have very large growth rings. why does this happen?

 

[Star-of-India]

Large growth rings are from what you might expect, a well fed growing tortoise. Like most living things, growth comes in spurts, generally seasonally with wild torts depending upon food supply. Captive torts grow in spurts and phases too depending upon food supply, the species and their individual genetics.

 

[russian/sulcata/tortoise]

Thank you!!! amazing answer!