If the concept of sin was invented for any creature, it was surely the echidna. For within the loins of this spiny little mammal – native to Australia and New Guinea – are hidden a multitude of deadly sins.
The first is lust. Every June to September, male echidnas trail after females in vast noisy groups like teenagers at a music festival. Their second sin is envy, because the echidna’s sperm is capable of bunching together into rival-hating blobs 100-sperm strong, whose goal it is to block off other potential suitors in the female’s reproductive tract. The third sin – sloth – applies only to the female echidna, as she is the only animal on Earth capable of being mated with while in the deep sleep of hibernation.
Thankfully, all four species of echidna score lower on the other sins. Unlike their wrathful cousin the platypus, they are not venomous, and they don’t score well on gluttony or greed either, because – unlike most other mammals – they lack a true stomach. And what about pride, the final sin? Let’s just say that the male echidna is rather well-endowed, with a four-headed penis otherwise unseen in nature. Whether or not you consider this something to be proud of is your call.
Subscribe to BBC Science Focus Magazine for fascinating new Q&As every month and follow @sciencefocusQA on Twitter for your daily dose of fun facts.