Wednesday, March 01, 2006

Wasps may help clean up blowies

It is now March and I have about 30 items in my backlog dated February that I haven't yet posted. So I am going to try cut them down to the bare minimum and post them singly or in small groups in rapid succession with my brief comments (bold and in square brackets), until I have cleared my February backlog. But then no doubt I will have a March backlog! I sympathise with Sisyphus!

Wasps may help clean up blowies, ABC, February 10, 2006. ... Queensland researchers are closer to coming up with a control for the age-old rural problem of blow flies. They are a particular concern in intensive agricultural systems like cattle feedlots and poultry farms. The Department of Primary Industries is trialing a native wasp at a cattle property in the Brisbane Valley. The department's Rudolf Urech says spalangia wasps are being bred in Mundubbera before being released into the feedlot near Toogoolawah. "The parasitic wasp will sting the fly pupae and by that they kill the fly and produce another wasp," he said. "Those parasitic wasps are one of the natural existing controls of flies and all we are doing is enhancing the number of wasps in the feedlot and by that helping nature along to control the flies." ... [These "parasitic wasps [that] are one of the natural existing controls of flies" presumably are in the Ichneumonidae family, of which Darwin after admitting to Asa Gray that he wrote "atheistically" claimed, "I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars":

"With respect to the theological view of the question. This is always painful to me. I am bewildered. I had no intention to write atheistically. But I own that I cannot see as plainly as others do, and as I should wish to do, evidence of design and beneficence on all sides of us. There seems to me too much misery in the world. I cannot persuade myself that a beneficent and omnipotent God would have designedly created the Ichneumonidae with the express intention of their feeding within the living bodies of Caterpillars, or that a cat should play with mice. Not believing this, I see no necessity in the belief that the eye was expressly designed. On the other hand, I cannot anyhow be contented to view this wonderful universe, and especially the nature of man, and to conclude that everything is the result of brute force. I am inclined to look at everything as resulting from designed laws; with the details, whether good or bad, left to the working out of what we may call chance. Not that this notion at all satisfies me. I feel most deeply that the whole subject is too profound for the human intellect. A dog might as well speculate on the mind of Newton. Let each man hope and believe what he can." (Darwin C.R., letter to Asa Gray, May 22, 1860, in Darwin F., ed., "The Life and Letters of Charles Darwin," [1898], Basic Books: New York NY, Vol. II., 1959, reprint, p.105)

Actually, I have no problem with the "beneficent and omnipotent God" revealed in the Bible, for the purpose of having ecosystems of richer species diversity (see Ps 104:24), having created (mediately) parasitic wasps as a biological control of other rapidly multiplying insects like flies which, if they were allowed to multiply unchecked, would in short order cover the land to a depth of metres extinguishing all other land animal life and then extinguishing themselves!

Others like Macbeth (and I) see in such "marvels ... a tour de force by a virtuoso", citing the aptly namely "potter wasp" Eumenes amedei:

"... many animals behave in incredibly complicated and mysterious ways. ... These are marvels, beyond any doubt; but there is no compelling reason to regard them as adaptations. Each is a tour de force by a virtuoso, but the virtuoso seems to be exercising his own fantasy rather than adapting himself to mundane conditions in a utilitarian way. The books are full of examples of this virtuoso work, which is especially common among insects. I will set out one case at length to show how many refinements there can be and how the whole performance shows a master hand. In early summer the small wasplike Eumenes amedei of northern Africa and southern Europe emerges from the pupal state as an elegant insect with yellow and black bands. Soon after mating, the female prepares a house in which her young can develop and sufficient food can be stored. She chooses an exposed and sunny situation on a rock or wall, and builds a circular fence of small stones and mortar, the mortar being made from dry flinty dust mixed with her own saliva. The stones are chosen with care, flint being preferred to limestone, and the fragments selected are all much the same size. Her choice of the most polished quartz fragments suggests (if we are anthropomorphic) that she is not indifferent to the esthetic effect of her handiwork. As the wall grows higher, the builder slopes it toward the center and so makes a dome which, when finished, is about the size of a small cherry. A hole is left at the top, and on this is built a funneled mouthpiece of cement. The next task is to collect the food supply for the future grub. This consists of small caterpillars about half an inch long, palish green, and covered with white hairs. These caterpillars are partially paralyzed by the sting of the Eumenes and are unable to make any violent effort to escape. They are stored on the floor of the cell. Since they remain alive, they keep fresh until the grub is ready to eat them; if they were killed outright, their flesh would soon dry up or rot. When the cell is stocked, a single egg is laid in each house, and the mouthpiece at the top of the cell is closed with a cement plug, into which a pebble is set. The egg is not laid upon or among the caterpillars, as in many allied species. These caterpillars are only partially paralyzed, and can still move their claws and champ their jaws. Should one of them feel the nibblings of the tiny grub, it might writhe about and injure the grub. Both the egg and the grub must be protected, and to this tend the egg is suspended by tiny thread of silk fastened to the roof. The caterpillars may wriggle and writhe, but they cannot come near it. When the grub emerges from the egg, it devours its eggshell) then spins for itself a tiny silken ribbon-sheath in which it is enfolded tail- uppermost and with head hanging down. In this retreat it is suspended above the pile of living food. It can lower itself far enough to nibble at the caterpillars. If they stir too violently, it can withdraw into its silken sheath, wait until the commotion has subsided, then descend again to its meal. As the grub grows in size and strength, it becomes bolder; the silken retreat is no longer required; it can venture down and live at its ease among the remains of its food. The stone cells are not all stored with the same wealth of caterpillars. Some contain five and some ten. The young females, larger than the males, need twice as much food. But note that the cells are stocked before the eggs are laid, and that biologists generally believe that the sex is already determined when an egg is laid. How does the Eumenes know the future sex of her eggs? How is it that she never makes a mistake? (Macbeth N., "Darwin Retried: An Appeal to Reason," Gambit: Boston MA, 1971, pp.70-72)

The author of my zoology textbook, while not going as far as Macbeth, nevertheless considers the behaviour of Eumenes (which BTW is not in the family Ichneumonidae but in the (presumably closely related) family Vespidae) as something very special, for fashioning "dainty little narrow-necked clay pots, into each of which she lays an egg. ... paralyzes a number of caterpillars, pokes them into the opening of a pot, and closes up the opening with clay":

"Much of the behavior of insects, however, is not a simple matter of orientation but involves a complex series of responses. ... A female potter wasp Eumenes scoops up clay into pellets, carries them one by one to her building site, and fashions them into dainty little narrow-necked clay pots, into each of which she lays an egg. Then she hunts and paralyzes a number of caterpillars, pokes them into the opening of a pot, and closes up the opening with clay. Each egg, in its own protective pot, hatches to find a well-stocked larder of food awaiting it." (Hickman C.P., Jr., Roberts L.S. & Larson A., "Animal Diversity," [1995], McGraw-Hill: Boston MA, Second Edition, 2000, p.224)

No explanation is given how (or why) a Darwinian `blind watchmaker' process would go to such trouble! But I have (and indeed the article) explained why an Intelligent Designer would do it - biological control.

I have added Darwin's quote above to my "Problems of Evolution" book outline, section PE 3.4.1. "Evolution is anti-God (atheistic)", with the comment:

In the following quote, Darwin admitted to the Christian botanist Asa Gray that he wrote "atheistically" but then weakly tried to excuse himself by claiming that he "had no intention to" do so and then tried to shift the blame onto God for creating "the Ichneumonidae [a family of parasitic wasps which have an important role in maintaining biological control of flies] with the express intention of their feeding within the living bodies of Caterpillars" and even "that a cat should play with mice"!: [Darwin quote here] It is revealing that Darwin admitted that his reason for seeing "no necessity in the belief that the eye was expressly designed" was because of his disbelief in "a beneficent and omnipotent God"! That is, Darwin's science was ultimately based on his religious views, i.e. his belief in what God would not do.

Stephen E. Jones, BSc (Biol).
"Problems of Evolution"

1 comment:

John Umana said...

Evolution/ID debate: a cosmological perspective
The focus of science should be: what can be known from the scientific record? It is often stated that scientific statements must be verifiable, that is, capable of verification. Science restricts itself to the measurable, observable universe of matter and energy in their various forms. Yet I submit that far more can be known from scientific investigation and analysis about ultimate questions than has been recognized by many scientists. In fact, the question “Why is there any matter at all?” is also a scientific question, though we may not yet have an answer to it. Why is there energy?
In considering the evolution/ID debate, I’d like first to offer a distinction. A great deal of the debate, sometimes rather heated, on evolution suffers from confusion because lots of scientists fail to distinguish two different senses of the term ‘evolution.’ Please see
Best regards,
John Umana
Washington, DC