Single-celled organisms were believed to be little more than blobs of jelly in Darwins day. So-called 'simple' life forms. But there is nothing simple about them. Even within the humblest bacterium there are myriad chemical processes taking place and even miniature machines.

One molecular machine called kinesin transports proteins from one part of the cell to another along molecular roadways called microtubules.

Kinesin is responsible for transporting molecular cargo -- including chromosomes (e.g. during cell division), neurotransmitters and other important material -- along microtubule tracks from one region of the cell to another. It is driven by ATP hydrolysis, thereby converting chemical energy into mechanical energy which it can use for movement. A kinesin molecule typically possesses two tails on one end, which attach to the cargo, in addition to two globular heads (often called "motor domains") on the other end.

Watch this incredible animation of it apparently 'walking'!

Some bacteria have a miniature outboard motor called a flagellum. It has all the parts you would find on an electric motor only this one is so small you could fit 800 on the cross-section of a human hair!

The bacterial flagellum is an example of an 'irreducibly complex' machine. Take one part away and it no longer works. All parts must exist at the same time and be assembled together in the correct order. This suggests 'design' and therefore a 'designer'. If you visited Earth from another planet and discovered an electric motor, a clock, an ipod, a 747...you would never conclude that such devices fell together piece by piece by accident over a long period of time. No - you would conclude that they were designed - that there was some intelligence behind their construction.