I can't get the aphids out of my mind. (I'll resist a quip about 'bugging'.)
You lose an element of self control when breakfast time is at half past five, before leaving for work at six. Piers appears with his customary industrial-sized portion of muesli, while I am working on my equally customary slice of toast and yeast extract. 'Wholesome crusts make strong disciples.' I tell him about the honeydew on the lime trees. "'Syphuncles'," he says, correcting my quoted 'cornicles' for the tubes where the goo excretes. "Hmmm." I can't hold back the self-justification; "I do try to get stuff in my blogs accurate."
I hasten to the other end of the aphid anatomy. "Yea, but did you know about the pressure relief valve in their heads? The sap's..." "Phloem," Piers corrects (there are two types of sap.) "Yea, phloem... is at up to 40 bar. When they poke into the plant cell structure to feed on the sap, this valve stops their heads getting blown off! How about that for a neat bit of evolutionary advantage?" By now we're roaring like schoolboys. "Bad luck for the millions of others before one happened to come along with that genetic mutation!" Piers throws in for good measure. "I'm going to do a question for Reasons to Believe," I grin, and grab the car keys.
Reason To Believe (RTB) are top guys. In 2003 I did a magisterial quartet of Sunday morning teachings on Paul's speech in Athens. At Acts 17 verse 24, 'The God who made the world and everything in it is the Lord of heaven and earth', I included what I considered to be the best current position on the scripture and science dialogue. I touched on the age of the earth, common origin evolution and human ancestry. I researched painstakingly; and afterwards got letters of complaint. It was an imperfect attempt - had I tried to have it both ways? I prayed that somehow, somewhere, God would connect me with an author or ministry that grappled with the question credibly. Meanwhile I was wavering.
I briefly enjoyed the Intelligent Design material, covering 'irreducible complexity' and the like. Then on an Xmas Day walk to Flamborough Head, I scrutinised the dizzying chalk cliffs. I couldn't bring myself to reconcile that it had all got laid down in three hours one Thursday afternoon about 3,000BC, as the young earth catastrophic flood brigade would probably wish I could. And yet I also know of instant creative miracles, where stumps produced feet (Smith Wigglesworth) or a withered arm grew (the gospels).
After we moved to Leeds in 2006, I spent another four years on this pilgrimage. Then I came across an audio of Hugh Ross (RTB's founder) in a debate on an apologetics-related website. He calmly stated that 'the earth was formless and empty' (Genesis 1:2) was about as good as the Hebrew could get to describing the creation of a planet around a sun emerging in a galactic star nursery. He went on to say that the early atmosphere would be translucent but opaque, so 'light' (from the perspective of an observer) would exist but the sun would be unidentifiable. After a stable the water cycle was established ('separated the water under the expanse from the water above it', verse 6), the atmosphere would be transparent as now. I was awed. Why hadn't anyone explained this before?
On of the regular Reasons To Believe podcasts invites questions, which are answered unscripted online. I've had a couple included. So, I was as good as my word to Piers. I sent them:
'I was trimming the shrubs under the mature lime trees in our garden, and noticed the vast amounts of honeydew on the leaves. My biology-savvy friend says this is the excretion from aphids. He explained how they consume masses of sugary sap (phloem) to get sufficient nitrogen for their diet. I checked out that aphids penetrate plants with a feeding device called a stylet. The phloem is at high pressure: I've seen up to 40 bar quoted, but seven to ten seems common. So, to stop its guts being blown out, aphid's head anatomy has a cibarial pump to regulate the pressure. Remarkably, when aphids switch to feeding on xylem sap, at negative pressure, the same pump draws in the foodstuff. And there's even protective regulation by osmosis for the relative chemical concentrations between the aphid's digestive system and the sap. Is this unique?'
Listen for it on http://www.reasons.org/explore/type/i-didnt-know-that
I'll spare you an elaboration on the aphid's use of its own fluids to overcome the plant's in-built defences against losing nutrients, and the osmotic regulation process. Hmmm. Genetic mutation evolutionary advantage?
My aphids source was http://www.societyofbiologyblog.org/a-shootful-of-sugar/
You lose an element of self control when breakfast time is at half past five, before leaving for work at six. Piers appears with his customary industrial-sized portion of muesli, while I am working on my equally customary slice of toast and yeast extract. 'Wholesome crusts make strong disciples.' I tell him about the honeydew on the lime trees. "'Syphuncles'," he says, correcting my quoted 'cornicles' for the tubes where the goo excretes. "Hmmm." I can't hold back the self-justification; "I do try to get stuff in my blogs accurate."
I hasten to the other end of the aphid anatomy. "Yea, but did you know about the pressure relief valve in their heads? The sap's..." "Phloem," Piers corrects (there are two types of sap.) "Yea, phloem... is at up to 40 bar. When they poke into the plant cell structure to feed on the sap, this valve stops their heads getting blown off! How about that for a neat bit of evolutionary advantage?" By now we're roaring like schoolboys. "Bad luck for the millions of others before one happened to come along with that genetic mutation!" Piers throws in for good measure. "I'm going to do a question for Reasons to Believe," I grin, and grab the car keys.
Reason To Believe (RTB) are top guys. In 2003 I did a magisterial quartet of Sunday morning teachings on Paul's speech in Athens. At Acts 17 verse 24, 'The God who made the world and everything in it is the Lord of heaven and earth', I included what I considered to be the best current position on the scripture and science dialogue. I touched on the age of the earth, common origin evolution and human ancestry. I researched painstakingly; and afterwards got letters of complaint. It was an imperfect attempt - had I tried to have it both ways? I prayed that somehow, somewhere, God would connect me with an author or ministry that grappled with the question credibly. Meanwhile I was wavering.
I briefly enjoyed the Intelligent Design material, covering 'irreducible complexity' and the like. Then on an Xmas Day walk to Flamborough Head, I scrutinised the dizzying chalk cliffs. I couldn't bring myself to reconcile that it had all got laid down in three hours one Thursday afternoon about 3,000BC, as the young earth catastrophic flood brigade would probably wish I could. And yet I also know of instant creative miracles, where stumps produced feet (Smith Wigglesworth) or a withered arm grew (the gospels).After we moved to Leeds in 2006, I spent another four years on this pilgrimage. Then I came across an audio of Hugh Ross (RTB's founder) in a debate on an apologetics-related website. He calmly stated that 'the earth was formless and empty' (Genesis 1:2) was about as good as the Hebrew could get to describing the creation of a planet around a sun emerging in a galactic star nursery. He went on to say that the early atmosphere would be translucent but opaque, so 'light' (from the perspective of an observer) would exist but the sun would be unidentifiable. After a stable the water cycle was established ('separated the water under the expanse from the water above it', verse 6), the atmosphere would be transparent as now. I was awed. Why hadn't anyone explained this before?
On of the regular Reasons To Believe podcasts invites questions, which are answered unscripted online. I've had a couple included. So, I was as good as my word to Piers. I sent them:
'I was trimming the shrubs under the mature lime trees in our garden, and noticed the vast amounts of honeydew on the leaves. My biology-savvy friend says this is the excretion from aphids. He explained how they consume masses of sugary sap (phloem) to get sufficient nitrogen for their diet. I checked out that aphids penetrate plants with a feeding device called a stylet. The phloem is at high pressure: I've seen up to 40 bar quoted, but seven to ten seems common. So, to stop its guts being blown out, aphid's head anatomy has a cibarial pump to regulate the pressure. Remarkably, when aphids switch to feeding on xylem sap, at negative pressure, the same pump draws in the foodstuff. And there's even protective regulation by osmosis for the relative chemical concentrations between the aphid's digestive system and the sap. Is this unique?'
Listen for it on http://www.reasons.org/explore/type/i-didnt-know-that
I'll spare you an elaboration on the aphid's use of its own fluids to overcome the plant's in-built defences against losing nutrients, and the osmotic regulation process. Hmmm. Genetic mutation evolutionary advantage?
My aphids source was http://www.societyofbiologyblog.org/a-shootful-of-sugar/
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