Irreducible match of orchid and moth?

Irreducible match of orchid and moth?

From a book by Darwin on orchids I had heard contained a passage about a prediction Darwin had made based on the length of the “nectary” of a species of orchid in Madagascar that was ten to eleven inches long. Quite a long “nectary,” which raised the question, what species could reach that far inside the orchid to enjoy its nectar and pass along the orchidʼs pollen to the next orchid? Darwin reasoned that “in Madagascar there must be moths with probosces capable of extension to a length of between ten and eleven inches!” No such moth species was known at the time, and they were only discovered years after Darwinʼs death. The length of the nectary appears to have evolved along with the length of the tongue of a particular moth species (perhaps other moth species were also evolving longer tongues at first, but only this species was able to keep up with the lengthening of the orchid?).

Was a designer playing games in designing this oddly irreducible match between this species of orchid and this species of long-tongued moth? Or did this irreducible match come about by virtue of the moths with the longest tongues surviving to continually lick up a source of nectar available only to them? Any strong opinions either way?
Best, Ed

The writings of Charles Darwin on the web
by John van Wyhe Ph.D.

Darwin, On the various contrivances by which British and foreign orchids are fertilised. London, John Murray, 1862.

Chapter V.

I fear that the reader will be wearied, but I must say a few words on the Angræcum sesquipedale, of which the large six-rayed flowers, like stars formed of snow-white wax, have excited the admiration of travellers in Madagascar. A whip-like green nectary of astonishing length hangs down beneath the labellum. In several flowers sent me by Mr. Bateman I found the nectaries eleven and a half inches long, with only the lower

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inch and a half filled with very sweet nectar. What can be the use, it may be asked, of a nectary of such disproportional length? We shall, I think, see that the fertilization of the plant depends on this length and on nectar being contained only within the lower and attenuated extremity. It is, however, surprising that any insect should be able to reach the nectar: our English sphinxes have probosces as long as their bodies: but in Madagascar there must be moths with probosces capable of extension to a length of between ten and eleven inches!

[…]

If the Angræcum in its native forests secretes more nectar than did the vigorous plants sent me by Mr. Bateman, so that the nectary becomes filled, small moths might obtain their share, but they would not benefit the plant. The pollinia would not be withdrawn until some huge moth, with a wonderfully long proboscis, tried to drain the last drop. If such great moths were to become extinct in Madagascar, assuredly the Angræcum would become extinct. On the other

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hand, as the nectar, at least in the lower part of the nectary, is stored safe from depredation by other insects, the extinction of the Angræcum would probably be a serious loss to these moths. We can thus partially understand how the astonishing length of the nectary may have been acquired by successive modifications. As certain moths of Madagascar became larger through natural selection in relation to their general conditions of life, either in the larval or mature state, or as the proboscis alone was lengthened to obtain honey from the Angræcum and other deep tubular flowers, those individual plants of the Angræcum which had the longest nectaries (and the nectary varies much in length in some Orchids), and which, consequently, compelled the moths to insert their probosces up to the very base, would be fertilized. These plants would yield most seed, and the seedlings would generally inherit longer nectaries; and so it would be in successive generations of the plant and moth. Thus it would appear that there has been a race in gaining length between the nectary of the Angræcum and the proboscis

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of certain moths; but the Angræcum has triumphed, for it flourishes and abounds in the forests of Madagascar, and still troubles each moth to insert its proboscis as far as possible in order to drain the last drop of nectar.

I am familiar with this puzzling case. But, try to write out a specific detailed Neo-Darwinian genetic sequence for it.

Me? I canʼt even write out a genetic sequence to make Cambellʼs soup. Darwin knew there were moths with longer tongues than most other species of orchid pollinators [like butterflies and bees and flies] and those moth species pollinated orchids with longer nectaries than most. Darwin assumed in this extraordinary case it was a moth with a tongue ten to eleven inches long getting to the nectar. He was right.

Do I know why the orchidʼs nectary evolved to such a length, or why the mothʼs tongue continued evolving to such a length to reach the base of the nectary? Perhaps because as the nectary grew longer the nectar became the sole property of whomeverʼs tongue could reach it, and thus a nitch for food opened up that no other creatures could reach, ensuring that whomever reached that niche could have all the spoils to themselves, a rich prize. And only those whose tongues could reach it, continued to reach it. While the shorter tongued cousins of the long-tongued moths settled for more hotly contested shorter nectaries, or grew extinct.

Philosophe, If you are out of your depth, perhaps you will accept my suggestion that no one can describe the genetic sequence, which at best would only be a series of guesses.

What is a philosophe? Someone from Voltaireʼs day? And what did it used to mean to call someone “Ms. Philosophe?” (Is Ms. an abbreviation of “Monsieur?”)

I agree with you that I am out of my depth. Who isnʼt “out of their depth” at this point and with our limited knowledge? I bet that moth and its near cousins in Madagascar are no where near having their genomes elucidated and compared and evolutionists are no where near understanding how everything functions and changes in such species.

For the rest, you seem to be describing a directed evolutionary theory, not evolution with chance alteration of the genome, a path I am confident you do not want to follow. It did not require much ingenuity to propose that such a flower would require an insect with a long tongue, or one small enough to make the trek by foot.

I thought about the question the same way, and thought why not a really small insect like a teeny beetle creeping down that ten to eleven inch long nectary for the nectar? Maybe because a single moth with a long tongue made more sense based on the cousin species of moths that already pollinate cousin species of that species of orchid in Madegascar, and Darwin assumed that evolution works with whatʼs already there?

Perhaps you might like to try your hand at writing some scenarios for the separate development of the human sex organs. You might even make the explanation amusing, perhaps leading to a Hollywood contract.

Wow, what a challenge! And a Hollywood contract to boot! But didnʼt Woody Allen already do the movie version of Everything You Ever Wanted To Know About Sex But Were Afraid To Ask? Seriously, Lynn Marguilis has written on the evolution of sex, though I donʼt know if sheʼs talked much about the evolution of human sex organs. From what little I know it does appear that in the womb early on we are all “female” moreso than “male,” relatively speaking. The gonads remain relatively in place for females while the male of the species has his gonads descend via two openings in the lower abdomen, and the tubules that lead from his gonads to his urethra have to grow longer since they are stretched up and around the tubules leading from his kidneys to his bladder (do I have that right?). The male prostate is another confusing matter, and doesnʼt appear to function very well where it is, causing difficulties with urination, especially as we age. (Speaking of difficulties as we age, whatʼs with “wisdom teeth” anyway?) As you can see Iʼm out of my depth in this matter as well. But are I.D.ers more in their depth concerning such subjects?

Daring scientists to explain one thing and then another thing, first the moth and orchid, then the evolution of sexual organs, including all the environmental/sexual/embryonic selective pressures and the kind and order of genomic mutations that occured over periods of thousands to millions of years, seems quite a task to demand of anyone.

Knowing that such matters have not been explained, I.D.erʼs jump in and explain it their way, by saying “it was a Designer!” I.D. class in college is going to be relatively short if most explanations come down to “Thatʼs just the Designer doing his thing, donʼt ask him how! That would be like trying to peek in Godʼs closet and thereʼs no point to that, since we already know itʼs I.D.” (Less Christian instructors will add that the Designer might also be aliens or time travelers.)

It does not appear to me that the I.D. explanation will take science any where, though it will doubtlessly absorb the minds of children with unquestioning reverence of some sort, toward either God, aliens or time travellers.

Still, I must add that there are also Darwinian Christian evolutionists who have reverence for God. Todayʼs prime example might be biologist Kenneth Miller who continues to debate with I.D.ers head to head.
Another such Christian appears to be Howard Van Till who refuses to align himself with the I.D. movement. Around the turn of the century there were others. See Darwinʼs Forgotten Defenders: The Encounter Between Evangelical Theology and Evolutionary Thought by David N. Livingstone. They appear to agree that perhaps a creation that required constant miraculous adjustments over zillions of years wasnʼt such a great reflection on the creator after all. But if creatures evolved naturally and death and change were part of natural processes, as natural as new stars being formed and new elements being formed from simpler elements inside stars, then the Creator was all the more impressive in having been able to set such things up right from the beginning. I mean, itʼs one thing to have to keep pulling rabbits out your hat every day or century or year, but to make human beings out of seventeen-billion-year-old hydrogen, well, thatʼs even more impressive than making a human being out of a single cell in nine months. Itʼs quite a trick, makes the constant dipping into the magic hat look repetitive, tiresome. And then to also produce creatures curious enough to study and rediscover the whole natural process and follow the clues backward, why thatʼs quite an inspiration to enhance curiosity. Can I.D. truly compare with that?

“How I hate the man who talks about the ‘brute creation’ with an ugly emphasis on brute…As for me, I am proud of my close kinship with other animals. I take a jealous pride in my Simian ancestry. I like to think that I was once a magnificent hairy fellow living in the trees, and that my frame has come down through geological time via sea jelly and worms and Amphioxus, Fish, Amphibians, Reptiles, and Apes. Who would exchange these for the pallid couple in the Garden of Eden?”
W. N. P. Barbellion

“When the rationality of the hross tempted you to think of it as a man…it became abominable — a man seven feet high, with a snaky body, covered, face and all, with thick black animal hair, and whiskered like a cat. But starting from the other end you had an animal with everything an animal ought to have…and added to all these, as though Paradise had never been lost…the charm of speech and reason. Nothing could be more disgusting than the one impression; nothing more delightful than the other. It all depended on the point of view.”
C. S. Lewis, Out Of The Silent Planet (a Christian science-fiction novel)

So what if Darwinism gives atheists solace. Are the atheists to be denied solace? Is God, the true God and creator, really as insecure as creationists assert, and always going around blaming people for if they donʼt believe in him and praise him for everything? Maybe heʼs not particularly proud of everything he sometimes gets praise for? Like miraculous football passes, or finding oneʼs eyeglasses? Maybe he leaves a lot up to us, and likewise up to nature, because letting things do their own thing is cooler than being a micro-manager? Maybe thatʼs Godʼs lesson to us. And likewise, maybe he doesnʼt take credit when things go wrong either, like extinctions or volcanoes. A cosmos that runs itself and evolves itself is gonna have things that run into one another, jury-rigging is expected. Maybe this is not the best of all possible worlds, just the best of all possible Self-Evolving worlds? Anyway, thatʼs my three hundred dollars and Two Cents on those matters.

I originally brought up the “irreducible long-tongued moth and long-nectary orchid” because it seemed pretty straightforward: Lengthening nectary, lengthening tongue over time. Seems like it could happen, knowing other moths with longish tongues and orchids with longish nectaries. Though a designer might just as well have left both the length of the tongue and the length of the orchidʼs nectary of average size. (Thereʼs only a single known species of bedbug that stab-rapes other males of the same species so as to inject them with his sperm that then finds its way through the stabbed maleʼs organ into the female he has stab-raped. Other species of bedbug only stab-rape the female in the abdomen and the males do not stab-rape each other. Likewise though the Bombardier beetle has a moving squirt appendage which can direct its heated chemicals. Other cousin species donʼt have the moving appendage, and they spray the chemicals outward and also on themselves. And beetles of that type already produce the hydroquinones that are used in other capacities in beetles and already have anatomical divisions that could be used as the two chambers to store those chemicals. And thereʼs only one bird species than can fly backwards. And thereʼs only one species of orchid and moth with such very long tongues and nectaries. So for every marvelously specialized species there appear to be lots of less highly specialized cousins sharing similar anatomies and physiologies.)

Was the lengthening of the orchid and the lengthening of the mothʼs tongue directed? Who knows? The antlers on the heads of Irish elk apparently grew to increasing lengths over time, and then no more Irish elk, they became extinct. (Because of the increasing size and length of their enormous antlers? I donʼt know. No one knows. But the antlers of the Irish elk do appear to be of an awkward length — jutting out so far to each side — that I imagine just swinging itʼs head quickly from one to side to the other might create enough momentum to strain itʼs neck — not a genuine hypothesis, just a joke based on the momentum of twisting and twirling objects, not to mention how such antlers could make it difficult to maneuver and double park in a forest full of trees). Perhaps that orchid with its long nectary might become extinct one day, having specialized itself into extinction, and if that moth is only especially attracted to that orchidʼs nectar it too could become extinct. There are tapir-like species in the fossil record that show up again later in time with increasingly elongated noses and a pair of elongated teeth until species with longer noses and longer front teeth appear and finally the first elephants with trunks and tusks appear. All thatʼs left today are the modern day tapir and the modern day elephant with those other species between them having gone extinct. If I.D. is life-giving and every one of its irreducible specializations demonstrates the farsighted perfection of an intelligent Designer, then why all the extinctions? Why are the earliest birds more like ancient reptiles than modern day birds? I mean if we found a hummingbird (the only one that can fly backwards) among the earliest birds, Iʼd be surprised, but we donʼt. We find birds with reptilian shaped triangular skulls with the same shaped individual skull bones as reptiles, and other features that label them as “birds in progress.” (How competent a Designer are we talking about?) And then once the progress has been achieved every early birds is wiped out. In this case the early bird did not catch the worm, it caught the grave. And this happens time and again. Mammal-like reptiles. Wiped out. All those mesyonchids with those weird shaped ear bones that resembled early whaleʼs ears, wiped out, not good enough I guess. (How competent a Designer are we talking about?) All those early Eocene whales, Ambulocetus, Rhodocetus, Basilosaurus, wiped out. Leaving only the species we see today, which still pop out embryonic hind legs in the womb where they are reabsorbed — or in some cases are not completely reabsorbed and we find a grown whale with bumps on its hind regions that contain (when x-rayed) a small femur, tibia, fibula and phalanges. (How competent a Designer are we talking about?)

Those are questions that I think are as valid as any others.

1 comment:

  1. If they believe moth and orchid are irreducibly unevolving, they should rethink its caterpillar to moth stage. :smile:

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