That's all wives-tale BS,.....however I do have several photos saved on my computer of a few different types of captive-bred snakes eating their own tales as far up as they could possibly swallow out of starvation or pure instinctive feeding response from seeing their own tails move, NOT to roll down hill to chase someone..LOL! 
The "getula" complex of common kingsnakes is the most noted for doing this because they are absolutely voracious feeders, even when not thin from lack of food. But I have also seen photos of cornsnakes that did this too, and that was definitely out of pure starvation unfortunately.
~Doug
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"a snake in the grass is a GOOD thing" 

serpentinespecialties.webs.com

