"When offered various bacteria as potential prey, [the viruses] attacked only it."
Any insights on how that might work, beyond attacking every option but only succeeding in one? Viruses are presumably too simple to make a strategic choice.
βTo enter a host cell, bacteriophages attach to specific receptors on the surface of bacteria, including lipopolysaccharides, teichoic acids, proteins, or even flagella. This specificity means a bacteriophage can infect only certain bacteria bearing receptors to which they can bind, which in turn determines the phage's host range. Host growth conditions also influence the ability of the phage to attach and invade them.β from Wikipedia
Any insights on how that might work, beyond attacking every option but only succeeding in one? Viruses are presumably too simple to make a strategic choice.