Science in School: The Blob

Aarna Pal-Yadav

When someone says “the blob,” you probably think a giant, hungry, slime-thing because that’s how sci-fi classics from the 1950s portray them. This is not actually the case. Physarum polycephalum has been dubbed “the blob” by visitors of the Paris Zoological Park. Unlike its namesake, the blob is a unicellular, mustard-yellow organism the size of a small animal – and no, it does not eat people- but it does have many other interesting characteristics. It’s not an animal, it’s not a plant, and it’s not a fungi – so what is it? It’s been classified as a protist because it doesn’t fit in any category. Even through “the blob” has existed for over one billion years, it’s only gained the attention of the public since the Paris Zoological Park opened the aptly named “The Blob” exhibit for it this month.

Even though this strange organism has no brain nor neurons, it can learn, make decisions, store long-term memories, and find its way through a maze.

Also, blobs hate light, drought, salt, and caffeine, but love oats for not apparent reason. Even though it has no eyes, it can detect oats put into its environment by researchers and digest them without a mouth or stomach. Researchers found if one blob trained to ignore caffeine (instead of running away) fused with another blob, the new organism would ignore caffeine. This shows that when the blobs fuse, they share knowledge.

The blob learned to ignore caffeine when researchers in Japan tested them. They set up a track in which oats was placed opposite to the blob with caffeine in the middle. At first, the blob was unwilling to go near the caffeine but it soon learned that touching the caffeine doesn’t harm it.

Furthermore, researchers put the organism on a miniature model of Tokyo in which the rail systems were made of oats. The blob turned itself into a replica of the rail system in order to reach the oats quickly.

The blob is amorphous, meaning it has no form or limbs. Despite this, it can move at four centimeters per hour. To put that in perspective, its mile time would be about 4.66 years. That doesn’t sound like much, but considering it has no limbs, that’s quite good! It moves through a process called “shuttle streaming” in which it shoots out a goo, known as protoplasm, which propels the organism forward.

Additionally, Rachel Feltman of Popular Science found that when a blob is cut by a scalpel, the cell’s many nuclei (the organelle with the cell’s hereditary information) attempt to reform the cell by coming together. As Dr. Feltman put it, “Really, though, this super-quick healing ability is less like healing and more like being able to drop your arm and then pick it back up and pop it on, Mr. Potato-Head-style.” Also, since the cell has many nuclei, the cell can spread itself and grow significantly.

Last but not least, the blob has 720 sexes, so the reproduction process is quite complex. When they do reproduce, however, the blob’s cytoplasm (the fluid of the cell) is from both parents. In humans, however, the cytoplasm is only from the mother’s side. Overall, all single-celled organisms aren’t boring – the blob is only one example of a unicellular organism with amazing qualities.