On the western coast of America, a combination of cool fog and salty sea spray keeps the soil moist all year round. In these wet conditions, you’ll find an unassuming plant called the yellow monkeyflower. Drive further inland, and the climate changes considerably. It’s hotter and drier, and every summer brings a harsh drought. But here too, the yellow monkeyflower blooms but its lifespan is shorter and its leaves are less luscious. Despite their different habitats and lifestyles, both groups of monkeyflowers are members of the same species. But that might eventually change.

Since their discovery in 1921, scientists have found examples of these genetic inversions all over the place. For example, around 1,500 of them separate the chimp genome