How can slime mold learn? But it does….

Wired investigates an organism – not even an animal, doesn’t even have internal organs or nerves, much less a brain – that still somehow learns to avoid unpleasant things:

Petri dishes full of P. polycephalum cells, grown inside agar jelly, were placed near oatmeal and inside jelly. They were separated by a “bridge” of jelly, which the slime crawled across in around two hours. Two separate bridges were then contaminated with bitter concentrations of quinine and caffeine.

The slime initially hesitated, and even stopped for several hours before moving slowly across the bridge, attempting to not touch the bitter substance, to reach the food.

But after several days of trials, this time was cut down – which the team says means the slime had become habituated to the bitterness.

“What’s interesting about slime moulds is that they appear to be simple, but they are capable of amazing stuff,” said lead author Roman Boisseau.

This includes an ability for the mould to find its way around mazes and even choose the best diet for itself….