Cod evolve right outta here

According to the New Scientist, our appetite for cod is causing them to go into turbo-evolution.

It seems there are two types of cod - ones who keep to deeper waters and those who are happiest higher up.

But those latter fish get have a much higher chance of getting caught up in a net.

So, through (un)natural selection, more and more cod still alive today are those who like to stay low.

Now scientists always thought fisherman exerted a selective pressure on fish, which in some cases has led to smaller fish. The smaller fish escape the nets and therefore their 'small' gene gets passed on.

But researchers always thought this was a slow process. But the latest study from the Iceland cod fishery, practically the only large cod fishery in the world, has shown the process could be much, much quicker.

Scientists reckon Iceland's cod stocks could go the way of the Newfoundland cod fishery, which crashed in 1992 and has never recovered.

So enjoy your cod and chips - it might be your last.

This reminds me of the 'Samurai crab' of Japan. These bear a shell which for all the world looks like a Samurai warrior. It's uncanny.

Locals believe the crabs are the reincarnations of past warriors.

But this is a case of man playing god. Over the centuries fishermen have thrown back any crab with such markings on its shell. Who would want to eat their old mate?

And so, over time, more and more of the Samurai crabs survived, while their plain old mates ended up on a dinner plate.

In the end there were only crabs with blokes face on their shells left.

Weird Science Factoid: The animal with the largest brain in relation to its body is the ant. So next time someone says you have the brain of an ant, take it as a compliment!

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