Pain: Evolution or Curse?
It doesn’t take much “evolution” to create a toxin, or to switch on or amplify the pain response. Are these good things gone bad?
Simple origin of scorpion sting: In “How scorpion gets its sting,” Science Daily says that scorpion venom may have started out as a benign protein in the defensin class. Defensins are so named for their ability to fight off viral, bacterial or fungal pests. A new paper compared scorpion venom to a particular defensin, and found that it could have evolved by a single genetic event. “The most significant findings of our paper are the predictability of scorpion toxicity evolution — arising via structural deletion of a loop on an ancestral defensin scaffold recruited into the venom to remove steric hindrance of peptide-channel interaction,” said the lead author of a paper in Molecular Biology and Evolution. This suggests that a simple one-time change to an existing protein led to a “functional shift of proteins from fighting against microbes to attacking prey.” The BBC News describes how the team converted a defensin into a toxin with the single change.
Short circuit turns up pain dial: Another Science Daily article describes how pain can be intensified by a “short circuit” in ion channels in the cell. Drugs that try to close the channels to reduce pain sometimes increase it. Why? The closure creates a leak, allowing more hormones to enter. “This ‘electrical leak’ activates the pain nerves, thus increasing the sensation of pain.” One particular ion channel, TRPM3, acts as a “molecular fire detector,” the article says.
Parasite prevents locust swarm: Locust plagues can be devastating to local economies, wiping out the food supply, as described in the Old Testament book of Joel and the plagues of Egypt. PhysOrg describes how locust swarms begin with runaway production of aggregation pheromones by gut bacteria. These hormones, however, are kept in check in some populations by a microsporidian parasite. Chinese scientists found that the parasite acidifies the locust hindgut, reducing the production of aggregation pheromones, effectively switching off swarming behavior and returning the insects to individual behavior. They don’t know why the parasite would want to reduce swarming, since it counter-intuitively would seem to reduce the parasites’ ability to spread. While they work on that, they hope that artificial pheromones can reduce swarming without pesticides. Their paper is published in PNAS.
Update 1/19/14: The locust genome has been decoded, Science Daily reported. Surprisingly, it is the largest genome of any animal deciphered so far: 6.5 gigabases. It seems the genome has been subject to excess transposable elements and gene repetitions, some of which may be implicated in the swarming behavior.
This entry augments the 12/17/13 entry about natural evil. It doesn’t solve all the theological/philosophical problems with the origin of natural evil, but does illustrate how minor changes can sometimes create major effects. Some aspects of the curse may not have involved direct creation of pain-causing machines, as much as God releasing nature to take its own course. Without the same level of divine providence, things could break down, forcing living things to adapt to broken things, using their designed mechanisms for robustness in the new regime of the curse. In other cases, balances that had been maintained by dynamic equilibrium (homeostasis) before sin were allowed to shift, leading to catastrophic consequences like locust plagues.
Man’s disobedience turned Earth into a rebel base. A holy God would be justified in destroying it, now that it contained a dangerous infection (consider the Flood – and the possibility that fallen angels brought the infection of evil to a new level). Still, God is longsuffering and gives man time to repent. He demonstrated His love for us in that, while we were still sinners, Christ died for us (Romans 5:8). The Creator became incarnate and lived among us, taking on our judgment on the cross, so that we might have a way out of the curse and have hope of paradise regained. See our previous commentary for reasons the evolutionary story is no comfort (or explanation) at all.