
Benzoxazinoids are produced in very different plants, such as the zebra plant Aphelandra squarrosa (left), the golden dead-nettle Lamium galeobdolon (right) and maize. Comparative studies of the plant metabolites and the genes expressed have now demonstrated how flexible plant metabolism is. The formation of benzoxazinoids in the three species is based on different enzyme classes and has thus evolved independently of one another.
© Karin Groten, Max Planck Institute for Chemical Ecology
Imagine for a moment that you're a supremely intelligent designer and you just designed a metabolic pathway for producing a substance in plants that is intended to deter other creatures you designed earlier to eat the plants, from eating them.
No! I know that's not an intelligent thing to do but work with me on this one!
Then, the same problem you've created which the animals you've designed doing what you've designed them to do, and eating other plants you've designed, so how do you solve that problem?
Being intelligent, you give those plants the same metabolic pathway to produce the same deterrent substances you've just designed, don't you?
Well, yes, if you were truly intelligent you would, but not if you're creationism's putative intelligent [sic] designer. If you're creationism’s putative intelligent [sic] designer, you set about creating entirely new metabolic pathways for each plant to produce the same deterrent chemicals! In metaphorical design terms, it’s the equivalent of inventing the wheel anew every time you need to put wheels on a cart.
Would you employ such a designer?
Creationists regard this as supreme intelligence - which probably tells us a great deal about creationists and probably explains why they're creationists in the first place.
You might think this example is made up to make creationists look even more gullible, but it's actually based on real science as revealed recently by researchers from the Max Planck Institute for Chemical Ecology, Jena, Germany. These researchers have found that distantly related plants use different enzymes and different biochemical pathways to produce the defence compounds, benzoxazinoids, and with different enzymes come different sets of genes.
The researchers found that these biochemical pathways have evolved in plants at least three time and don't have their origins in a common ancestor.