The following has been contributed by a friend, after reading the latest claims by the bushmeat people in the paper by Faria et al. I hope you like it. I think it provides a fresh and rather astute asessment of what is going on.
Ed Hooper, 3 November 2014
Once upon a time medical science was accused of causing a great plague with millions of victims. The accusation caused much weeping and gnashing of teeth, consternation, denials and lawsuits.
Medical science tried to defend itself, but its proofs fell to pieces when examined closely.
So medical science consulted haruspices* who promised to read the entrails of the plague and absolve medical science of responsibility. That would be good, said medical science.
[*Haruspices, singular haruspex, practitioners of haruspicy: divination by reading entrails of the dead.]
So the haruspices studied the entrails of the plague and divined deep into the past. We see that the plague was present 100 years ago, before your responsibility could begin, said the haruspices. You are absolved.
Medical science honored the haruspices, but still there were unbelievers.
Tell us more, asked medical science.
In the year 1920 we see an individual harboring the plague, replied the haruspices. The face of the individual is hidden by the mists of time, but we see this individual harboring the plague in a river-port city on the great Congo River in Africa. The entrails tell us that all of the plague descends from this one individual.
Tell us more, asked medical science, how did this individual get the plague?
This individual got the plague indirectly from a chimpanzee living in the jungle more than 500 miles to the north, said the haruspices. From there traders must have brought the plague down rivers and across rivers to the individual in the port city. Chimpanzees don't like to cross rivers.
What happened to the traders?
The entrails show that after delivering the plague, the traders, and anyone else who had caught the plague, died off leaving only the one individual in the port city to pass it on.
Then what happened?
The entrails tell us, said the haruspices, that after 1920 the plague spread at an exponential rate of 10% per year, with a doubling time of about 7 years.
Before he died, probably of the plague, our first individual had to pass the plague on to two more people so that by 1927 there were 2 carriers of the plague.
Then these 2 people had to pass the plague on so that by 1934 there were 4 carriers of the plague. Maybe more than 4 people caught the plague, but they had to die before passing it on. Otherwise the entrails would have gone all crazy.
The entrails tell us that for 1941 there were 8 people carrying on the plague in the port city on the great Congo River.
Of course, peering through the mists of time by examining entrails is not an exact divination, and there could be some variation in these numbers, said the haruspices. Nevertheless, for the year 1948 we see 16 people carrying the plague in the port city. The carriers were so few and hard to see, even close up, that the doctors and hospitals in the port city did not notice that people were dying of the plague.
But the numbers kept growing, said the haruspices. By 1955 our divination has to account for rounding errors, so there were 33 living carriers of the plague that year; most earlier victims having died awful deaths, of course.
The plague continued to grow exponentially at a 10% rate each year.
The effective number of plague carriers was 37 in 1956, 40 in 1957, 45 in 1958, 49 in 1959, said the haruspices, although some adjustment for what we call the the mean viral generation time might be required, such is the mystery of divination.
Right about then, in the late 1950s, the haruspices declared, the entrails show something strange happened. The plague suddenly mutated into 10 sub-plagues, a starburst it is called, and the sub-plagues started growing exponentially at a new much higher rate of 27% each year.
We have actually examined an entrail from 1959, said a haruspex, the oldest ever found, so we know this is true.
Then, with the sudden starburst and the jump in exponential growth, the plague leaped from the Congo basin and into the world. Soon it was everywhere, and millions were dying.
And, said the haruspices, the entrails prove it is all because of Africans eating wild game instead of processed food. Medical science is absolved.
But, said a sceptic, what if instead of crossing rivers themselves, chimpanzees were brought in cages and on boats from the northern jungles to a compound way upstream on the great Congo River for medical science trials and experiments in 1957-1960 that involved a million African subjects? Couldn't that lead to a simpler explanation for the origin of the plague and the starburst of the sub-plagues?
Oh, no! said medical science. That would be an ugly theory. Only a heretic, a conspiracy theorist would propose such an awful thing. You must not suggest such things in public.