Analysis of the organ structure in fossils allows us to make estimates of how far back evolutionary relationships go. The wild cabbage plant is a good example. Humans have over more two thousand years, cultivated wild cabbage as a food plant, and generated different vegetables from it by selection. This is of course, artificial selection rather than natural selection. Kale, cauliflower. Broccoli, cabbage, Red cabbage and Kohl rabi all these have same ancestor.