"A female digger wasp not only lays her egg in a caterpillar so that her larva can feed on it, but carefully guides her sting into each ganglion of the prey’s central nervous system, so as to paralyse it but not kill it. This way, the meat keeps fresh. It is possible the prey might be aware of being eaten alive from inside but unable to move a muscle to do anything about it."

(Richard Dawkins, River Out of Eden)

Is nature really so barbaric and callous? The digger wasp is but one example of the indifference of nature and evolution. But is it all so cruel? The natural world contains astonishing beauty and in this Blog I want to highlight some amazing evolutionary stories and share my awe and passion for one of the most important theories ever conceived by mankind.

Friday, 10 October 2014

Shrimp Claws Strike as Quickly as Bullets

Mantis shrimp sport powerful claws that they use to attack and kill prey by spearing, stunning or dismemberment. In captivity, some larger mantis shrimps are capable of breaking through aquarium glass with a single strike.

Mantis shrimp have two raptorial appendages on the front of their bodies which accelerate with the same velocity as a gunshot from a 22 caliber rifle. In less than three-thousands of a second they can strike their prey with 1,500 Newtons of force. If human beings were able to accelerate our arms at just one-tenth of this speed we would
be able to throw a baseball into orbit. 



The front limbs of the mantis shrimp move so quickly that the water around them boils. This process is known as supercavitation. When the supercavitation bubbles burst an underwater shock wave is produced that can kill the prey even if the shrimp missed them with it's strike. 






Mantis shrimp also have extremely sophisticated eyesight, their eyes are considered the most complex in the animal kingdom. They possess sixteen colour receptive cones (humans have only three) and can perceive both polarised light and multispectral images. It has been suggested that the capacity of these shrimps to see UV light enables observation of otherwise hard to detect prey on coral reefs, a great selective advantage.

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