It doesn’t take much to turn a friendly bacterium into a killer.
A Medical Xpress article, “From friend to foe: How benign bacteria evolve to virulent pathogens,” describes how quickly good germs can become dangerous to humans through interactions with the immune system:
Isabel Gordo and colleagues from the Instituto Gulbenkian de Ciencia in Oeira, Portugal, have for the first time devised an experimental system to observe and study the evolution of bacteria in response to encounters with cells of the mammalian immune system. They found that in less than 500 bacterial generations (or 30 days), the bacteria became more resistant to being killed by immune cells and acquired the ability to cause disease in mice.
Commensal bacteria, like E. coli, live within the human body. The researchers forced unnatural interactions with E. coli by exposing them to macrophages – immune cells capable of swallowing invaders. This put intense selection pressure on the bacteria:
When the scientists looked at the interaction between new variant bacteria and macrophages more closely, they found that the small colony variants were more resistant to being digested by macrophages than the ancestral strain, and the mucoid variant was less likely to be gobbled up. When they infected mice with mucoid variant bacteria, they also found that the variants have increased ability to cause disease in mice.
This means that harmless bacteria, resistant to the normal give-and-take of symbiosis, were able to swarm and overwhelm the host, disrupting cooperative interactions and leading to disease. All this happened quickly, within a few hundred bacterial generations. The question then arises: why are so few bacteria harmful, and so many beneficial?
Update 12/20/13: Of all the surprises: a panel of experts recently discussed the benefits of parasites. Not just freeloaders, most of them are necessary for the ecology, and many are now being used to treat disease. (This is not to downplay the harm of some, like malaria and liver flukes.) Overall, parasites have gotten a bad rap, one parasitologist believes. The 53 minute audio panel is available from Ideas with Paul Kennedy.
The problem of natural evil challenges every worldview, because every living thing is stressed by pain and suffering. The evolutionist cannot call it evil, because it just is—it’s what evolution, a mindless, amoral process, produced. For theists dealing with the problem of evil (theodicy), the theistic evolutionist and old-earth creationist have to suppose that millions of years of suffering, pain and death were normal parts of the “very good” creation (see last chapters of Coming to Grips with Genesis for detailed analysis of the various theodicies). Only the Biblical view can regard natural evil as an unnatural intruder, the consequence of sin and the Fall of man. A straightforward, natural reading of Genesis as historical narrative (the way the apostles and Jesus Himself took it) locates the creation of humans near the beginning of the creation (on the sixth regular, normal day), after God had pronounced everything He had made “very good” (Genesis 1:31). With moral evil the fault of Adam and Eve’s disobedience, and natural evil a judgment due to sin, Biblical creationists can understand the groaning of all creation Paul described in Romans 8, and also can look forward to a paradise restored when the curse is lifted.
Understanding the basic principles, though, leaves many difficulties about the details. One possibility based on this news item above is that the curse on the world due to sin might have involved God relaxing His maintenance processes in creation. On this view, God did not create bad bacteria and parasites de novo, but (in an anthropomorphic sense) “took His hands off” the controls and let mutations occur apart from His direct control. Accordingly, mutations that broke the macrophages’ ability to regulate the numbers of bacteria could lead to terrible diseases. Still, this cannot explain all natural evil. Some of it appears designed for suffering. In Genesis 3, specific pain-causing effects were named as part of the judgment. Some think God gave Satan, as the “god of this world” mankind had chosen to follow, limited dominion to inflict evil for judgment or testing, but only within God’s permissive will (see Job 1). If you think things are bad now, even more horrendous things appear at the end of days in Revelation: beings sent to inflict torment on rebellious mankind. It is the right of a holy God to punish evil. Perhaps we should be asking how rebels can get off with such light punishment. Nature documentaries like to film the chase scenes – the cheetah taking down the antelope – because it would be boring to film the antelope growing up in good health for 10 years, with plenty of food. God remains merciful and gracious, extending His common grace even to beings who rebel against Him (see Acts 14:15–17). For more thoughts about natural evil, see point 3 of this outline rebutting skepticism.
Nevertheless, we all know that suffering strikes people unequally: bad things happen to good people, to innocent children, and to saints. These things cause us to cry out, “Why?” Jesus, the Lord of Creation who certainly knew, did not provide the kind of answer many of us are looking for. He said the sun and rain fall on the righteous and the unrighteous. He said unless each of us repents, we will all perish like those who became victims of political suffering and natural accidents. He said “Blessed are the merciful, for they will receive mercy.” He treated natural disasters (earthquakes, disease epidemics, asteroid impacts) and wars as part of what this period in earth history must expect – but He said He will never leave or forsake those who trust Him.
Natural evil presents other questions. Predator-prey relationships are part of the “balance of nature” today, so in what sense are they evil? What was the extent of the curse? How could a biosphere operate without death? We might be underestimating the changes that took place as a result of the curse on sin. We “see through a glass, darkly” Paul said (I Corinthians 13). Some day we will know fully as we are fully known. It’s important to think, read the Bible, and come to a point of having at least partial answers to these questions. Even if our answers are not exhaustive, they can provide sufficient grounds for trusting the Creator. Sufficient grounds can then motivate involvement in alleviating suffering the best we can, while we look forward to the “blessed hope” of the restoration of all things in a new creation without pain, death, and evil. When you are confident with that, get busy and help your brethren.
This is where the rubber meets the road. What are you going to believe? If you are an evolutionist, there is no hope. This is the new normal. Got sick? That germ was fitter than you. Got born into a dictatorship? The tyrant was fitter than you. Have a genetic disease or disability? Stuff happens. Got injured? Too bad. Tough luck. Sorry, pal. Who cares. That’s life. Buck up. Better luck next time. When it happens to you, better pray there is a merciful Christian around to stand beside you and give you hope. That’s the reason for Christmas, isn’t it? – good news of great joy for all people … and on earth peace among those with whom He is pleased.