Slime Molds Are Picky About Where to Eat, Despite Being Brainless

By Anna Rothschild

Slime molds have been popping up in the news quite a bit lately. A few weeks ago, they made headlines by mimicking the Japanese rail system. Now, a paper published in the Proceedings of the National Academy of Sciences shows that slime molds can make complicated choices about the amount and variety of nutrients they eat. It might not seem like a big deal that an organism—whether mold, mouse, or man—can make complex decisions about how to feed itself. Except that they have no brains. These amoeboid creatures have no specialized center dictating all their actions. So, as they spread across a landscape, they have no "mission control" to which to report their nutritional requirements. In the recent study, scientists placed 11 different foods around the outside of a Petri dish, each with a different protein-to-carbohydrate ratio. They then plopped a slime mold into the center of ...