[net.bio] Macro-evolution example?

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?