ABOVE: ILLUSTRATION © MARK MAWSON, GETTY IMAGES
It was a simple but insightful experiment. At the turn of the 20th century, American biologist Edmund Wilson squashed starfish eggs under a microscope and watched what happened as cellular material spilled out between two glass coverslips. He noted that the cellular goo contained spherical globules that fused into larger globules—behavior characteristic of liquid droplets suspended in another, chemically distinct liquid. Wilson also observed that only droplets of the same type (which he judged by their color or apparent density) fused upon contact with each other.
These observations led Wilson to conclude that “the living protoplasm” contains numerous liquid droplets that vary in their “chemical nature.”1 Despite having been overlooked for the last century, this has turned out to be a prescient description of the interior of eukaryotic cells.
In addition to membrane-encased organelles—the nucleus, mitochondria, and Golgi apparatus, to name a few—eukaryotic ...
