A Matter of Selection

One part of the Brassica oleracea plants that exhibit the most variation are the leaf length by the stem, lengthwise. For example, one kohlrabi leaf (by the stem) is 12 cm and a collard’s leaf is 38 cm (by the stem). I think that there is a lot of variability in domestic forms of Brassica Oleracea because artificial and selective breeding makes the plants have particular traits plant breeders want in their plants. Another reason is because of descent with modification, along with natural variation and mutations. The plants could randomly change at anytime due to mutations and natural variation. Natural variation is the process where mutations randomly occur when the genes are copied. The part of the plants that seems to be the same is the stems width. I think this is because they all are the same species and they only had mutations that affected other traits. Evidence of this is that 3 kohlrabi stems were about 1 cm in width and 3 collard stems were about 1 cm in width as well. In order for plant breeders to change this characteristic, they would have to breed with other plants or place the plants in an environment so they might be able to adapt to their new environment.