Diverse mobile genetic elements shape bacterial genome evolution and provide countless genomics tools. Tn7-like transposons are notable for their tight control of targeted transposition. In addition, the modular features of Tn7-like transposons allowed them to coopt and evolve diverse targeting pathways. CRISPR-associated transposons (CAST) are prime examples of the cooption process. In this thesis, I briefly introduce Tn7-like transposons, transposition mechanisms, pathway diversity, examples of gene cooption, and evolutionary convergence in Chapter 1. Chapter 2 presents my discovery and characterization of a novel cooption of type I-D CRISPR system by a Tn7-like transposon. Chapter 3 presents how type I-F3 CAST convergently evolved dual pathway lifestyles using categorized spacers and the genetic cooption of XRE-family regulators. Chapter 4 presents my bioinformatic work on type V-K CAST and the convergently evolved dual pathway lifestyles using categorized spacers facsimile to the type I-F3 CAST.