I think ivory size must be genetic i certain areas. Out here in montana where i hunt, they are easy to tell apart. Bull ivory is at least twice the size of the cow ivory. My sister killed a bull last year that was 9 years old and the ivory was so worn that the main bulbous part was completely worn off, but the root was still twice as wide as cow ivory. I can vouch for elk in other regions though. I really think it must be a genetic mutation from region to region on how big the ivories grow.

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