Humans contain 'alien' genes not passed on from our ancestors, researchers have discovered.

They say we acquired essential 'foreign' genes from microorganisms co-habiting their environment in ancient times.

The study challenges conventional views that animal evolution relies solely on genes passed down through ancestral lines - and says the process could still be going on.

Or, we acquired them from technologically advanced beings who deliberately 'engineered' them into our germ line.To read more, click here.