What can organisms without brains teach us about animal intelligence?

The word “intelligence” comes from the Latin inter-legere. Legere means “to choose” or “to speak” and comes from the root leg, Greek for “to gather.” Hence, “intelligence” can mean “to choose between,” implying that one gathers information about alternatives, then makes a decision.

Intelligence refers to a basic necessity of life; all living organisms need to make decisions. Yet, we equate intelligence with a brain. Such focus on the mammalian brain is not surprising. The mammalian brain is energetically expensive and thus must provide special abilities not found in brainless organisms.

But even humans base decisions on “best guesses”—obtaining complete information is almost always impossible. In addition, more and more evidence shows that we can make decisions without involving our brain. Ever wondered where the term “gut feeling” comes from?

This project applies established decision-making paradigms developed for animals to plants and slime moulds. The team aims to identify the origin of information storage and retrieval. They will use Pavlovian (classical) conditioning as our experimental paradigm for three reasons:

1. This is the form of learning that we know the most about in animals and thus allows for an in-depth understanding of learning in non-neuronal organisms,
2. It allows for direct comparison with animals, and
3. Other forms of learning are usually defined by how they differ from conditioning, hence requiring a good grasp of the properties of conditioning in the first place.

Madeleine Beekman’s research will pave the way for understanding what “extra” the mammalian brain provides. The project will thus work towards a true understanding of intelligence, and what confers brainy organisms like ourselves distinctive forms of intelligence.