This false-color confocal image shows fatty-acid liposomes compartmentalized in a clay vesicle. The clay vesicles are approximately 100 microns in diameter, and the pores in the clay tend to range in size from about 50 to 100 nanometers (nm), with a very small percentage of vesicles able to exclude molecules as small as 17 nm. Fatty acid molecules, thought to be the components of primitive organic cell membranes, have been shown to travel through the pores into the vesicle and automatically assemble into micron-sized liposomes. Credit: Photo courtesy of Anand Bala Subramaniam