Ow does the nature of Roman generalship change across the course of the Republic?

This is for a Roman history (Republic) course: How does the nature of Roman generalship change across the course of the Republic? What (if anything) changes and why (or why not)? Think structurally herenot just who a general fights, but what it means to be a general and what expectations surround this role. Be specific and historical hereground your discussion in the context of specific individuals and their context. Please restrict the examples to the Roman Republic period only. Scipio Africanus is a must. Thanks!