They are bioengineered to mimic the way deer antler bone grows through the skin.

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The sports world has been in a tizzy this week as Sports Illustrated alleged that earlier this year Ravens linebacker Ray Lewis used deer antler spray, which contains a growth hormone, to heal his torn triceps.

FORBES: Journalists and Performance-Enhancing Substances

In a story featured on SI.com yesterday, Sports Illustrated is reporting that Ray Lewis requested products (specifically, deer-antler spray which contains an NFL banned substance called IGF-1) from a small health supplements company based in Alabama.

FORBES: Should Ray Lewis Play in Super Bowl XLVII?

They include human teeth, the skull of a woolly rhinoceros, mammoth tusks and a tooth, flint tools and the antler of a giant deer.

BBC: Jersey Post mammoth stamps mark archaeological history