Thank you for the response. I feel guilty making you work so hard to explain it to me. I do think this is fascinating stuff!! I’m listening to an audiobook about the history of plagues called Get Well Soon, by Jennifer Wright. It’s not so long ago that humans were defenseless against microorganisms. How did they ever think they were Devine beings?? Obviously I’m being sarcastic here ;). I’m beginning to understand evolution at little better. Please do send any reading suggestions.