3. The Bait
Some nooks catch bits of cheese, while others develop scents that mice are attracted to. Nooks with bait are much better at attracting mice and now we don't have to chase them. We can just wait by the baited nook and smash the mouse with a shovel when it walks in. Eventually natural selection favors nooks with bait and plain nooks become irrelevant for catching mice and either die out or become repurposed.
A branching out of the mousetrap evolutionary tree happens when the floors of some of the nooks baited by scent alone, become sticky. In these nooks the mice become stuck and, if ignored by us, eventually die of starvation. These nooks eventually evolve into modern glue traps. Other nooks, baited by cheese, follow a different evolutionary path...