Yes all we can do is guess about why dogs were belligerent to Ted Bundy even on first meeting him, but their behavior was so belligerent it seems worth a thoughtful guess.
Have you ever had a dog act belligerent toward you?
How many encounters did Bundy have with dogs that did not elicit belligerent behavior? That seems worth a thoughtful guess also.
Three times seems like it could be coincidence. Twenty times, fifty times, now that would be pretty noteworthy.
Canine behavior has been widely studied, we know lots about their senses and how sensitive they are and I have never heard of a single study that suggested that any canines can sort saints from sinners or demons.
In my experience, dogs act belligerently toward strangers a lot and their owners say something like "Oh he doesn't usually act like that.", more often than not.
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