Genetic evidence from studies of flowering plants is showing that their evolution didn’t proceed by random mutation, but proceeded by building on previous genetic structure. It’s like a genetic Lego set:
Though a rose, carnation or tulip each has its own distinguishing feel, look and smell, they all share one common trait: the flower’s petals adorn its perimeter while the reproductive organs sit in the flower’s center.
In fact, just about every flowering plant ever cataloged follows this same pattern. Until recently scientists didn’t understand how this occurred.
[Plant biologist Detlef Weigel] “Now, we show that the pattern arose through clever recycling of another pattern that plants had previously used in shoots, for other purposes. This is a big step toward solving the “abominable mystery,” as Darwin put it ” the evolutionary origin of flowers and flowering plants.