A strong thesis statement for a literary analysis of themes within "The Call of the Wild" could be:
"In 'The Call of the Wild,' Jack London explores the theme that both the wild and civilization impose their own sets of rules, as Buck's journey reveals that survival requires an adaptation to these contrasting yet governing forces."
This thesis effectively encapsulates the main idea you want to convey, showing how Buck's experiences illustrate the broader theme of rules in both environments.