Closer examination of the animals' anatomy revealed that the sea slugs had a large part of their penis coiled up in a spiral inside their bodies, which they would then use to replenish their missing part.

BBC: Sea slug's 'disposable penis' surprises

You can find strong statistics, and useless investment signals from butter production in Bangladesh, the US population of 9 year old kids, and now, in a dramatic breakthrough, relating average penis size to GDP growth, a key measure of stock market returns around the world.

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Scarborough Hospital said it was prevented by patient confidentiality from revealing whether any operation to re-attach the man's penis had been a success.

BBC: News | Health | Man severs own penis

Right whales have one of the smallest brain-to-body-size ratios of any cetacean, the longest penis in the animal kingdom (averaging more than seven feet or 2.3m) and testes with a combined weight of one tonne.

ECONOMIST: The lives of whales