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Friday, October 31, 2014

Leaf Miners and Amazing Symbiosis

Posted by jlwile on April 29, 2010

This is the ADULT form of a leaf miner. Image from:
http://en.wikipedia.org/wiki/File:Cameraria_ohridella_8419.jpg

I ran across a short article on Creation Ministries International’s website that really intrigued me. It was about “green islands” on decaying leaves, which are patches of green on a leaf that is otherwise dead. I have seen these “green islands” many times, and I just assumed they were the result of areas in the leaf where the majority of chlorophyll just hadn’t completely decayed away. Perhaps that region was chlorophyll-rich and thus would take longer to lose its chlorophyll than the rest of the leaf. However, when the green spot is strongly localized, it is probably the result of the larval version of a leaf miner insect.


This really intrigued me, so I spent some time looking into leaf-mining insects, and what I found was truly incredible. First, there are a lot of leaf miners. Some are moths, some are flies, some are beetles, and even some are wasps. The adult lays her eggs in within the tissue of a leaf, and when the eggs hatch, the larvae begin eating the insides of the leaf. This, of course, protects the larvae, because they are not exposed to predators. They stay inside the leaf until they are ready to pupate (start metamorphosis into their adult form).

Now, of course, if a larva is “unlucky” enough to hatch shortly before or after the leaf falls from the tree, this could be a problem. After all, the larva is eating the living tissue inside the leaf and therefore needs the leaf to stay alive while it is feeding. What happens if the leaf dies before the larva is ready to pupate? Well, that’s where the “green islands” come in. It seems that the larva can keep the portion of the leaf it is eating alive so that it can continue to eat and develop, and that’s why the area around the larva stays green!

So how does the larva do this? How does it keep its part of the leaf alive, even when the rest of the leaf is dead? Well, for a long time, this was quite a mystery. However, in 2007 David Giron and his colleagues published a study in which they analyzed dead leaves with leaf miner infestations. They looked at the tissues near the leaf miner larvae (which were still green) and compared them to dead tissues in the same leaf, living tissues in an uninfected leaf, and dead tissues in an uninfected leaf. They found that certain plant hormones (called cytokinins) were in abundance in the areas around the leaf miner larvae. In some cases, there were more cytokinins in the area around the leaf miner larvae that there were in the living tissue from an uninfected plant!

So the conclusion was clear. The leaf miner larvae were doing something to increase the amount of cytokinins in their area of the leaf, which was keeping that area alive. But what exactly were they doing? The authors weren’t sure. As they say:

First, high levels of cytokinins in mined areas could result from the overexpression of the plant genes which produce cytokinins in the infected zone. Oral secretions of feeding insects contain many specific compounds able to interact with plant gene expression…Second, cytokinins in mined tissues could result from an accumulation process rather than a synthesis per se. Feeding activity of leafminers is known to alter biophysical properties of leaves and consequently respiration and transpiration rates…Such processes strongly impact the flow of nutrients within a leaf and could potentially result in the accumulation of cytokinins in mined areas. Third, insects themselves could potentially synthesize cytokinins.

Well, it turns out that one of the co-authors (Wilfried Kaiser) on that study recently did another study that helps to narrow down the possibilities. He found that leaf miner larvae are infected with bacteria from the genus Wolbachia. It turns out that lots of insects are infected by these bacteria, so that wasn’t surprising.

The surprising thing happened when Kaiser cured the leaf miner larvae of their infection by administering an antibiotic. The leaf miner insects remained healthy, but they could no longer produce green islands. Thus the bacteria make the “green islands.” What’s still not completely clear is whether the bacteria make the cytokinins responsible for the “green islands” or they do something to help the leaf miner make them. We know that bacteria (the simplest living things on the planet) are significantly better chemical producers than the most high-tech chemistry lab we have, so my bet is that the bacteria are making the cytokinins.

Regardless of exactly how the bacteria help the leaf miner insects, this is yet another stunning example of mutualistic symbiosis. Quite some time ago I blogged about mutualism in nature. While simple forms of mutualism are easy to explain in an evolutionary framework, the complex ones are extremely hard to understand in an evolutionary framework. They are all over creation, however, so any theory that tries to explain origins must account for them at some point.

I personally think that mutualism shows us that lots of creatures were made for each other, and they are just one more facet of the amazing design that we see all around us.

Comments

11 Responses to “Leaf Miners and Amazing Symbiosis”
  1. “Extremely hard to understand” doesn’t mean it is untrue. Your writing is riddled with these types of slight-of-hand twisted meanings. For instance, quantum mechanics is super-duper extremely hard to understand, but it produces the the most precise predictions of any scientific theory ever tested.

    And there are virtually limitless examples of complex mutualisms in nature. It took me a couple minutes to find this one also involving chloroplast.

    Well of course they were “made for each other”! The question is by who or what? What DATA is there that supports the divine intervention of G-d as the maker?

  2. jlwile says:

    There are no twisted meanings here, Shooter. You simply cannot face the data, so you desperately hope you can find something wrong with the way I present it.

    When something is extremely hard to understand in a given scientific framework, that is evidence for the fact that there is something wrong with the framework. Quantum mechanics might be extremely hard to understand for someone who doesn’t have the training, but that is a reflection of the person, not quantum mechanics. The framework of quantum mechanics makes most of the data very easy to understand. Thus, quantum mechanics is probably a valid framework. There are a multitude of data that are extremely hard to understand in an evolutionary framework, indicating there is something very wrong with the framework.

    Thanks for reinforcing my point. I agree that there are virtually limitless examples of complex mutualism in nature, including the one you point out. Many of these complex mutualistic relationships are a serious problem for evolution and strong evidence for design in nature.

    The data that support that these mutualistic relationships were set up by God are all around you. I have covered several in this blog. You can find more here, here, and here.

  3. You call this evidence? My favorite parts:

    “There is an immeasurably and unimaginably huge universe out there (even though the most important part of it appears to be here).”

    “Scientists at ICR hold to the presupposition that the “uncaused First Cause” is the Creator who exists outside of the physical creation He made.”

    “Yet even more amazing (and the universe is amazing) is the historic fact that the Creator-God, after purposefully creating the time-space-matter universe, chose to enter it in the God-human person of Jesus Christ—for the sole purpose of providing a means by which humanity could have a personal relationship with the Creator.”

    The sole purpose was providing a personal relationship with God-human? That’s not even accurate Christian theology. If the ICR can’t even get theology (made-up stuff) right, how could they get science (how the world actually works) right?

  4. Or this?

    “So – what is the origin of music?

    It came from God. It was given to man at the moment of creation when ‘the morning stars sang together’ (Job 38:7). The Bible alone provides an acceptable explanation for the origin of music and musical instruments. We read in Scripture that God surrounds Himself with angelic choirs and the songs of the redeemed sinners (Rev. 14:2-3). A heavenly choir of angels sang at the birth of Christ. We are told to ‘sing to the Lord’ as Ills saints, to ‘praise His holy name’ (Psalm 30:4). Again, we are exhorted to ‘sing joyfully to the Lord’ and to ‘praise the Lord with the harp’, ‘make music to Him on the ten-stringed lyre’, ‘play skilfully and shout for joy’ (Psalm 33). The purpose of music was, and is, to praise God.

    Music provides joy because music has been provided by God.”

    I see the citations, but I can’t find any mention of the scientific journals Job (and why would the subject of Jobs deal with where music came from?), Rev. (Maybe it’s entirely written by Reverends?) or Psalm (And I know for a fact that Roxy Music didn’t use harps or lyres on their song Psalm).

  5. Signature in the Cell is a joke. Ha (Christian) ha ha (Christian). Although this one (Christian) contains something that isn’t funny at all:

    “I could go on about human features that betray a design that certainly is not intelligent. I will add only one more consideration. More that twenty percent of all human pregnancies end in spontaneous abortion during the first two months of pregnancy. That is because the human genome, the human reproductive system, is so poorly designed. Do I want to attribute this egregiously defective design to God, to the omnipotent and benevolent God of the Christian faith? No, I don’t. It would not do to say that God designed intelligently the human genome and that it then decayed owing to natural processes. If God would have designed the human genome, surely He would have done it so that this enormous misfortune would not happen. Think of it: twenty percent of all human pregnancies amount to twenty million abortions every year. I shudder at the thought of this calamity being attributed to God’s specific design of the human genome. To me, this attribution would amount to blasphemy.”

  6. jlwile says:

    Wow Shooter, I have upset you yet again. I know that when faced with the overwhelming evidence for God you do anything you can to distract attention from the data. Nevertheless, it is is fun to see that happen time and time again! If only you had the integrity of Dr. Anthony Flew, who gave up on his atheism when faced with the evidence.

    Obviously you are not the person to judge someone’s theology. Of course ICR has their theology correct when it comes to the atonement. Without the sacrifice of Christ, there would be no ultimate forgiveness of sin, so there would be no way for people to have a personal relationship with God. Of course, ICR presents an enormous amount of evidence for God’s existence, which you desperately avoid mentioning…

    Indeed, the very existence of music is a gift from God. If you listen to music, you have Him to thank, whether you admit it or not. Once again, you desperately avoid mentioning all the evidence posted at Answers in Genesis as well…

    Signature in the Cell is anything but a joke. This is why even an atheist scholar recognizes its importance. Indeed, many of the so-called reviews you linked do nothing more than demonstrate the desperation that people experience when they see that their preconceived notions are so fantastically wrong. The Biologos review is particularly bad, demonstrating that the reviewer had not even read the book and still clings to the fully-debunked idea of junk DNA.

    It is fun to read such reviews, as they demonstrate how effective Signature in the Cell really is! Just for completeness, here are some serious reviews of the book:

    Blown Away

    The Constructive Curmudgeon

    Spectrum

    Telicom

    The quote from the Biologos review also demonstrates how poorly Ayala reasons. Of course God designed the human genome, as its stunning complexity clearly reveals. At the same time, however, a very important event occurred a while back. It is called the Fall. That’s when all sorts of terrible things entered creation, including genetic decay. The human reproductive system is not poorly-designed, as anyone with a modicum of understanding of anatomy and physiology knows. However, the effects of the Fall cannot be avoided, as Ayala’s quote demonstrates.

  7. “Without the sacrifice of Christ, there would be no ultimate forgiveness of sin, so there would be no way for people to have a personal relationship with God.”

    Well, ICR said a personal relationship was “the sole purpose” of Christ and didn’t mention any intermediary steps. But what do you say about Moses? Surely he had a personal relationship with God before Jesus was even born.

    Oh, The Fall, right, that’s a scientific argument (not!): A snake told a woman to eat an apple, she did and because of that, 20% of all pregnancies are naturally aborted.

    Your last link is priceless. I really enjoyed the first blue box:

    The Gospel in Genesis 3:15?

    “And I will put enmity between you and the woman, and between your seed and her Seed; He shall bruise your head, and you shall bruise His heel.” —Genesis 3:15 [WTF?]

    Genesis 3:15 is known by the term Protevangelium, or “first gospel”—a prophetic picture of the time when Satan would be defeated by the woman’s triumphant “Seed.”

    The text itself invites us to find an interpretation [that we make up] that goes beyond mere biology. Satan, a spirit being, cannot produce seed; and clearly a woman does not produce seed. So, even at the simplest reading of this pronouncement, [no, the simplest reading is that it is crazy talk] the seed apparently refers to a spiritual being who has the serpent’s same attitude [what kind of attitude is that, bitchy?]

    Based on other scripture, it appears that the serpent’s “seed” refers to those who willfully set themselves against the seed of the woman [didn't this just say woman clearly doesn't produce seed?] (John 8:44; Ephesians 2:2–3). The age-long conflict between the Kingdom of God and the Kingdom of Satan (Matthew 13:37–40:1; John 3:8–12) will continue until the end (Revelation 12:17). “He” that crushes the serpent’s head refers to a future descendent [sic] of the woman and is a singular noun—which many Bible scholars believe is a reference to Jesus Christ

    There are many Bible scholars that believe that the earth is 6,000 years old too. Whoops, I can’t use that here.

  8. jlwile says:

    Shooter, you really don’t understand theology. This, of course, is not surprising. You don’t understand science, either, so why should you be better at theology? Moses certainly did not have a personal relationship with God. God spoke to him from time to time, and he did God’s bidding, but a personal relationship is much deeper than that, and such a relationship is not possible without the sacrifice of Christ. Once again, the atonement’s sole purpose was to allow a personal relationship with God. It accomplished this sole purpose by providing the ultimate sacrifice for our sins.

    The Fall certainly is a scientific argument. It is an event in history that affected the natural world quite significantly, and any attempt at explaining the natural world without reference to it will be flawed. This is why Ayala’s argument is so shoddy.

    I am glad that you enjoyed the last link. One day, those words you read might actually sink in.

    You certainly can use the fact that there are many Bible scholars who (not “that”) believe the earth is 6,000 years old. That is more consistent with the data at hand than the scientifically irresponsible notion of the earth being more than 4 billion years old!

  9. What is the scientific evidence that a snake told a woman to eat an apple, and when she did, a supernatural being got really pissed and condemned mankind to earthly suffering?

    What is the date of this historical event and what is the scientific evidence to support that date?

  10. jlwile says:

    Shooter, I know that logic isn’t your strong suit, but please try to pay attention here. Ayala is discussing the point from a CREATIONIST perspective. He is saying IF the creationist view is right, THEN God created a poor genome. So, for the sake of argument, he is ASSUMING the creationist viewpoint and seeing what it leads to. The problem is that he is not really assuming the creationist viewpoint, as the creationist viewpoint includes the Fall. Thus, from the creationist viewpoint, the Fall is a part of history, and it must be included if Ayala wants to see what the creationist viewpoint leads to. He doesn’t include the Fall, which shows how shoddy his reasoning is.

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