Wednesday 1 May 2013

At least I'm not a shark

Apologies for the lack of blogging activity lately, following my initial flurry. Rather predictably I've been busy being a Dad! As I may have mentioned, holding down a full time job while being as good a Dad as possible while also trying to retain some sense of self and former life – in other words drinking waaay too much and staying out past, ooh, 10 o'clock – can really take its toll.

Still, things are tougher in the animal world. Consider this piece from the fantastic science journalist Ed Yong. He points out that males have to compete for sex through a variety of elaborate rituals and cumbersome appendages, but that it doesn't end there.

In many animals, females exert a surprising amount of choice over who fathers their young. Even after sex, females can store the sperm of different partners in separate compartments and determine which ones get to fertilise her eggs.
For males, this means that sexual competition continues after sex. It’s not just about finding mates, but about ensuring that your sperm fertilises her eggs. This leads to fierce “sperm competitions” and bizarre adaptations, where males scrape away the sperm of past mates, guard or plug females so they can no longer accept partners, 'traumatically inseminate' her through her back, or even poison partners with toxic sperm to limit future sexual encounters.

But in sand tiger sharks this reaches new, cannibalistic levels… head over to the National Geographic site to find out more, but suffice to say that even if a male successfully fertilises a female's eggs he would be advised not to start bragging to all his mates about impending fatherhood just yet.


'I'm going to be a Dad! What? Oh no!'

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