Thursday 1 September 2016

The honeybee: intelligence in a miniature brain


A previous post referred to the widespread occurrence of intelligence in the natural world, even in brainless amoebae. See Intelligence without brains. It is obvious to everyone that hives have a kind of collective intelligence – a mystery in itself. But the individual insect within the colony also has intelligence, despite its miniature brain, the size of a grass seed.


For every hundred thousand neurons in the human brain (85 billion in all) there is only one in the bee’s equivalent. Here are some examples from the New Scientist in What’s the buzz? by David Robson (24 November 2012). They involve mental feats by individual bees and a growing repertoire of complex behaviour by groups of them. (NB Workers are all females and fall into two groups: foragers and nurses. Drones are males with the sole purpose of mating.)

  • The waggle dance is performed in the hive by a forager to indicate to her fellow foragers the direction and distance of nectar bearing flowers. This is well known. However, while it is performing this dance another foraging bee will sometimes butt the head of the dancer to indicate that it has found a spider at a particular place.

  • Nurse bees perform a wide variety of housekeeping tasks: spring cleaning, mutual grooming, guarding entrances against intruders and air conditioning in hot weather. The air conditioning is achieved by sprinkling water over the honeycomb and using their wings to produce a cool draft.

  • Workers have been observed to have over 60 patterns of behaviour, including 6 different kinds of dance. (Lars Chittkka Current Biology, vol.19, p.R995). This compares with 120 for bottlenose dolphins, 50 for beavers and 30 for rabbits.

  • Bees are aware of the concept of symmetry. If they see a variety of symmetric shapes and a variety of asymmetric shapes, and if they are rewarded only when a symmetric shape is chosen, they will select any shape which has symmetry from a random collection of shapes of all kinds.

  • They can find their way through a maze using abstract signs. They can also understand that different signs mean different things in different situations. They are much better than most primates at this.

     

  • When confronted with a variety of tasks they are able to assess their chances of succeeding and act accordingly. (The evidence for this is not conclusive but it seems likely from experiments to date.)

The article also points out severe limitations of the bee’s intelligence. Visual processing is confined to recognising outlines and only a small part of a scene can be taken in at once. Memory recall is very limited. Nevertheless this is another example of the extraordinary ubiquity of intelligence in the natural world, even in organisms with no neurons or brains as we understand them, such as amoebae. And it is my opinion that this is somehow connected with the process of evolution. Far from being a blind random process of natural selection plus random mutations evolution proceeds by intelligent cooperation and competition. Intelligence is a sustainer and driver of life.

Recently I became aware of plants which were precisely conserving their starch supply through the night using a simple mathematical formula and inputs from both their biological clocks and the number of starch molecules present in the plants.

It is also becoming increasingly apparent that intelligence in nature is not caused by arrangements of matter. These are secondary to something much more fundamental which is beyond our power to discern.

  
 Where it comes from is another question. Humans have an extraordinary variety and amount of reasoning capacity but I believe it is much more than this which makes us fundamentally different from the natural world around us.