A few days ago I spotted a mosquito on the bathroom wall. Now we’ve all seen mosquitos before but on this occasion I was fascinated by it’s size and anatomy – especially its incredible legs; thin as the finest silk thread.

How does Nature make such structures – and make them functional? Scientist though I am, it baffles my brain and I can quite see why some people believe in “intelligent design”.

Surely those legs cannot be anything more than stiff supports. Insects have an exoskeleton in contrast to our endoskeleton. The legs need nerves, muscles and circulation to make then more than fixed supports. Legs can move, allowing their owner to walk, clean itself, and even jump. The muscles have to attach to the inside of the exoskeleton, and there have to be nerves – and a method of supplying energy – to trigger them into action.

Insect circulation doesn’t work the way ours does as they do not have hearts: basically they use haemolymph which can diffuse around their small bodies, or be pumped by, for instance, muscular membranes. Some insects use this as a system of hydraulics, in combination with the muscles, to move legs etc. – apparently muscles to move a joint one way, and hydraulics for the reverse. All of which must be under some form of nerve control – and they don’t have that many nerves running from their tiny brains.

Even more weirdly, some insects (eg. jumping spiders, plant hoppers) have a system of gears which work their legs. Crazy or what?

Just how can these structures be created? You would think they’re so tiny they cannot be even one cell thick – but they have to be many, many cells thick. Which just goes to show how tiny our cells are.

I know evolution has had billions of years to achieve its designs, but I still struggle with how any living thing works or has evolved. Yes, I know the theories, and I can understand it as abstract pieces of mechanics and chemistry. However I really struggle coming to terms with how it all evolved, how it all works – together – and the sheer complexity of living organisms. When you think about it, it really shouldn’t be possible.