Tiny brain is no bar to intelligence, say scientists

Insects could be as bright as much bigger animals, despite their teeny-tiny brains, say scientists at Queen Mary, University of London.

Insects can show some pretty intelligent behaviours. Honeybees, for example, can count, categorise similar objects like dogs or human faces, understand ‘same’ and ‘different’, and differentiate between shapes that are symmetrical and asymmetrical.

This raises the question: what are big brains for?

While some increases in brain size do affect an animal’s capability for intelligent behaviour, many size differences only exist in a specific brain region, maybe conferring more highly developed senses or an ability to make precise movements. Research suggests that bigger animals may need bigger brains simply because there is more to control.

Professor Lars Chittka of Queen Mary’s Research Centre for Psychology, says: “In bigger brains we often don’t find more complexity, just an endless repetition of the same neural circuits over and over. This might add detail to remembered images or sounds, but not add any degree of complexity. To use a computer analogy, bigger brains might in many cases be bigger hard drives, not necessarily better processors.”

This must mean that much ‘advanced’ thinking can actually be done with very limited neuron numbers. Computer modelling suggests that counting could be achieved with only a few hundred nerve cells, and only a few thousand could be enough to generate consciousness.

Engineers hope that this kind of research will lead to smarter computing with the ability to recognise human facial expressions and emotions.

The research appears in Current Biology.