Can "Intelligent Design / Intelligent Origin Theory" be true if a species is so incredibly vulnerable to extinction? (Reproducing a large chunk of this, since I'm not sure how long it'll be before it retreats behind a firewall.)
...what can we make of the further complications that led the Large Blue butterfly (Maculinea arion) to extinction in Britain? It entrusts a critical stage in its life cycle to the tender care of a single species of red ant that is particularly finicky about where it nests.
The story goes like this: The Large Blue lays its eggs in the buds of thyme - the culinary herb that grows wild in Europe - in the tight-bud stage. If the butterfly is ready to lay its eggs before the buds appear, or not until after they have started to open, the brood is lost. The eggs hatch after one or two weeks, depending on the weather; warm weather speeds hatching. The young caterpillars feed on thyme flowers for about two weeks during late July and early August, then fall to the ground where they are "adopted" by red ants (Myrmica sabuleti) attracted by a sugary substance secreted from a dorsal gland. The ants carry the caterpillar back to their nest, where it then gorges on ant larvae. While hidden from its own predators, the caterpillar spends 10 months as a predator in the ant nest, and then pupates there. After three weeks pupation the butterfly emerges during the four weeks mid-June to mid-July.
M. sabuleti is a warmth-loving ant that thrives only in short, dry grassland on hot south-facing slopes that are heavily grazed. If the grass grows higher than 3-4 cm and shades the ground, cooling it, this ant dies out and other species of ant take over - ants that are not interested in providing free food and lodging for Large Blue caterpillars. Taller grass also crowds out thyme.
What happened in Britain was a constellation of events that conspired to spell disaster for the Large Blue. One was the increased use of chemical fertilizers that promote vigorous grass growth, which kills off small wild flowers such as thyme. Then, sheep were pulled off the land by a change in livestock farming. For a few years, rabbits spread and kept the grass short in habitats favored by the butterfly, but in the 1950s myxomatosis (a viral disease of rabbits) was introduced and eliminated them. Pastures also were previously burned over, which kept the grass short, but this is no longer done.
So here you have an insect that depends for its very existence on a fragile chain of circumstances that is easily broken by bad weather, changes in exposure to grazing due to human intervention and disease, loss of its unique food plant, and loss of its protector ant species. If I were to design such a silly system I'd at least choose the most abundant, hardy species of ant to host my caterpillars, and ensure that they could feed on other plants beside thyme, and at other stages than the bud. To me, the case of the Large Blue is conclusive disproof of the theory of intelligent design.
Interesting piece, but also interesting are the comments to the piece. For example:
ID is not about 'optimal design'
by Enezio E. de Almeida Filho
Intelligent Design Theory has nothing to do with 'optimal design', and this is something that Woodall seems to be unaware of. Has he read any books by William Dembski?
In that case, I wonder what an undesigned butterfly would look like?
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