I’m surprised that none of you pointed out that Caledonian’s original ‘objection’ - “It’s not logically necessary for ducks’ and robins’ disease transmissions to be symmetrical!”—was explicitly pointed out by me in the original text.
That’s probably because that wasn’t my original point.
My original point—which was the first three sentences of my very first post in this thread—is as follows: “What? No. It’s not even vaguely reasonable to say that a transfer of a disease between two species is equally likely either way.”
The point is correct. We would in fact expect it to be quite likely for any disease transfer to function far more effectively in one direction than equally well in both.
The reason favoring a robin->duck transfer over a duck->robin transfer is irrational is that we have no justification for saying which way the preferential transfer would occur. That was the correct point which you should have made, instead of the incorrect one that you did.
That’s probably because that wasn’t my original point.
My original point—which was the first three sentences of my very first post in this thread—is as follows: “What? No. It’s not even vaguely reasonable to say that a transfer of a disease between two species is equally likely either way.”
The point is correct. We would in fact expect it to be quite likely for any disease transfer to function far more effectively in one direction than equally well in both.
The reason favoring a robin->duck transfer over a duck->robin transfer is irrational is that we have no justification for saying which way the preferential transfer would occur. That was the correct point which you should have made, instead of the incorrect one that you did.