ark@rabbit.UUCP (Andrew Koenig) (03/24/84)
I recall an article in Scientific American that pointed out that broccoli cabbage Brussels sprouts cauliflower kale kohlrabi are all essentially man-made plants, having been derived by selective breeding over the past century from a wild form most similar to kale.
rej@cornell.UUCP (Ralph Johnson) (03/25/84)
Cabbage, cauliflower, etc. are all the same species. They have all the same pests (sigh!) and interbreed. They are no different from each other than different types of dogs. There are quite a few examples of recent speciation in plants, almost all are due to chromosome doubling and other catastophic events. There is a new species taking over the marshes of Great Britain that is a cross between a native marsh grass and the American species "cordgrass". I think I heard that it required chromosome doubling on the part of one of the parents, and that the new species will not cross with either parent. Any European botonists know otherwise?