Why do so many global trade issues come down to China's apparently insatiable demand for animal penises and other body parts?

Tigers, rhino, and deer are just a few of the poor creatures that many Chinese men turn to when seeking help in the bedroom.

That ugly trend comes though yet again today in this analysis from The Economist.

At issue: Canadian Prime Minister Stephen Harper's trip this week to China.

One of the conservative leader's economic goals in China is to persuade Beijing to kick-start a deal that opened Canada's seal products industry to the booming Chinese market.

The measure was important for Canada's small seal industry, which is collapsing due to export restrictions in the US and Europe, as well as high-profile global protests against the practice.

The problem for Harper — not the seals — is that protesters in China have delayed the start of the trade agreement, which was signed last year.

According to The Economist, Harper is now pitching hard to get Canada's seal business going in China:

“Our government will continue to vigorously defend this humane and highly regulated industry and seek new international markets for Canadian seal products, including China," he said upon departure.

Harper is trying to help Canada's highly-subsidized sealing industry, where culling has been cut nearly in half since 2009 (37,000 seals were killed last year, according to The Economist).

So why are the Chinese, in particular, interested in seals?

There's seal meat and seal oil, of course.

But, when powdered and mixed with wine, seal penis is sold as an aphrodisiac.

According to a 1998 report by marine biologist and journalist Susan Scott, seal penis has been know to sell for up to $500 a piece in traditional Chinese medicine shops in Toronto.

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