5 things you should know about slime mould

11 April 2019
In the lab with... Jules Smith-Ferguson
Jules Smith-Ferguson is a research student in our Experimental and Evolutionary Biology Lab, exploring the concept of minimal cognition by experimenting with slime mould.
Jules Smith-Ferguson holding an agar plate with slime mould growing on it

Jules Smith-Ferguson: see more of his research @suchisslime on Instagram

How can an organism without a brain make complex decisions, learn things or have a memory? That’s what research student Jules Smith-Ferguson is trying to find out.

“I’ve always been interested in the behaviour of different organisms, especially types of behaviours people consider cognitive like memory, learning and decision making,” he explains.

During his honours where he investigated the concept of minimal cognition in the History and Philosophy of Science, Jules was first introduced to slime mould.

Physarum polycephalum growing on an agar plate

The slime mould Physarum polycephalum is grown in agar plates and typically fed oats.

“The behaviours this organism is capable of and the experiments people had done with it, blew me away.”

Since starting his PhD in the Experimental and Evolutionary Biology Lab, he has been exploring the minimally cognitive behaviours of the slime mould, Physarum polycephalum.

“I wanted to explore this living system and try to work out what it can do and how. It has some rather remarkable behaviours for something which is essentially a big bag of slime,” he said.

24 hour timelapse of slime mould growing.
Credit: Marta Ferracin.

“It’s also about continuing the history of research on non-conventional organisms – the types of things most people don’t know exist but that can draw fascination from anyone, whether they’re super keen on science or not.”

In case you haven’t heard of slime mould before, we asked Jules to share some of his favourite facts about this curious organism.

5 things you should know about slime mould


You can chop it up and put it back together
Slime mould can be chopped up into lots of smaller little pieces, which given enough time can all move around as individuals. You can then bring the pieces back together, and after a little reorganisation, they will act as one big individual again.


It’s just a big bag of slime
Slime mould is just one giant cell with lots of nuclei inside - and these things can grow to be quite large under the right conditions. To think you're looking at this huge bag of slime and there's no cell wall or cell membranes dividing it up internally is pretty crazy. 


Slime is actually beautiful (at least to me)
The yellow colour is amazing. It forms these networks of tubules and waves of migrating slime that can create beautiful patterns. Sometimes I just like looking at it. 


Thrives off a diet of oats and water
Slime mould loves to eat oats! We grow it on agar plates which gives it enough moisture to thrive and we also put oats on the plate for it to eat. The growth rate depends on how much food you give it and how big it is to start with, but it'll take 2 to 3 days for a small subsection of slime to eat the oats and fully explore a 14cm petri dish.


You wouldn’t believe what it can do
Slime mould has been used for a range of things in research that are really fascinating. It has been shown to find the shortest path through a maze, it can recreate human designed transport networks, it has external and internal memory systems and can transfer information between two different slime moulds (kind of like one slime mould teaching another slime mould how to behave).