Explore the evolution of gravel bikes and their relationship with mountain bikes. Several sources discuss the increasing similarities between the two types, such as wider tyre clearance and slacker geometry, raising concerns about gravel bikes losing their unique identity and potentially becoming obsolete. However, other sources argue that key differences, particularly weight and intended use, will ensure the continued existence of gravel bikes, even as they become more versatile. The debate centres on whether gravel bikes' increasing capabilities will cause them to merge with or surpass mountain bikes in the market, or if a distinct niche will remain. A final source presents a discussion about this very topic, concluding that while the lines are blurring, both types of bike will likely persist.