Although I have posted on this article before, I don’t think Wolf-Ekkehard Loennig and Heinz-Albert Becker’s Nature Encyclopedia of Life Sciences article on carnivorous plants has received the attention it merits. The section on the origin of carnivorous plants (pp 5-6) discusses not only the spectacular examples of irreducible complexity that can be seen in these plants, but also the issue of “evolutionary convergence”. While the similarities between species in the same branch of the evolutionary “tree” may suggest common descent, similarities also frequently arise independently in separate branches, where they are better explained by common design than common descent. Loennig and Becker note that “carnivory in plants must have arisen several times independently of each other…the pitchers might have arisen seven times separately, adhesive traps at least four time, snap traps two times and suction traps possibly also two times.”
I used one of these carnivorous plants as an example of irreducible complexity back in 1985 in an appendix of my first book here. These elaborate traps have no conceivable function until almost perfect, until they are able to catch and digest insects, and the authors point out that even the functioning traps are of dubious survival advantage to the plants–they seem to thrive just fine without catching anything. The idea that the struggle for survival could have driven the construction of these traps is, to put it mildly, ludicrous.