114
7 Communication
or two brothers. He wouldn’t, of course. The evidence shows that it doesn’t work in
practice.
Group selection, with more tightly cooperating groups growing and displacing their rivals, may have contributed to the evolution of sociality in early hominids, but evolution of social insects rather followed individual-level selection,
from queen to queen, with the worker caste being an extension of the queen phenotype (Wilson, 2012). Ant and bee queens stepped on an unusual pathway of evolution. Whereas other animals gradually improved the body design of coming generations, the queens honed instead the self-organized interaction network within their
extended bodies distributed among their progeny. This overcame the limitations of
insect anatomy, which does not allow them to grow to a vertebrate’s size.
It is quite common to marvel at the clever organization of ant, termite, and bee
communities. They are, of course, as much unlike ours as insects are unlike mammals, but these creatures with diminutive brains have managed to build clean and
ventilated nests, collectively forage, care for their larvae, even domesticate other insects, and survive in this way for a hundred million years. Ants, as well as other social insects, are indistinguishable and mutually replaceable within their caste. There
is no one in charge in the anthill; the queen does not rule, she just bears her progeny,
replacing short-lived worker ants. Not unlike bacteria, ants self-organize by interacting chemically, by emitting or sensing pheromones, or visually and mechanically,
when encountering other ants. These interactions are not specifically addressed, ants
distinguish their kin and nestmates from a stranger but don’t say “hello, John, nice
to see you again”: any ant in a particular colony is like any other ant. What counts,
is the frequency of encounters that provides “quorum sensing”. There is no persistent specialization. Any worker ant can carry out any work, although the response to
stimuli varies with age, and it may be possible to discern an elite of “exceptionally
active or entrepreneurial individuals” (Oster and Wilson, 1978).
Workers are mobilized for urgent tasks, be it food delivery or nest repair, and in
case of trouble either hide in the nest or attack the invader, but no one tells them
what to do, and they have to decide it independently. This calls for a sophisticated
communication language. Decisions on work allocation are taken in response to a
pattern of inputs, either attractive or repulsive, including environmental stimuli, frequency of encounters with workers busy on particular tasks, and visual and olfactory
signals. Relevant information may assume specific forms; thus, ants mark trails to
food sources using pheromones, and bees indicate them by “dancing” movements.
Processing this involves a kind of mental computation, and requires memory. The
cognitive power of an insect’s brain makes feasible what a microbe swarm could
never achieve.
Still, all actions are “robotic”; it would be quite feasible to program automata
to operate in this way. This would not need a billion euro budget of the European
Human Brain Project (Sect. 7.2). It can also be imitated by a not too complicated
mathematical model (Gordon, 1999). Moreover, cooperation is not perfectly coordinated: among a group of ants carrying a load, one can observe individuals pulling
in opposite directions.
7 Communication
or two brothers. He wouldn’t, of course. The evidence shows that it doesn’t work in
practice.
Group selection, with more tightly cooperating groups growing and displacing their rivals, may have contributed to the evolution of sociality in early hominids, but evolution of social insects rather followed individual-level selection,
from queen to queen, with the worker caste being an extension of the queen phenotype (Wilson, 2012). Ant and bee queens stepped on an unusual pathway of evolution. Whereas other animals gradually improved the body design of coming generations, the queens honed instead the self-organized interaction network within their
extended bodies distributed among their progeny. This overcame the limitations of
insect anatomy, which does not allow them to grow to a vertebrate’s size.
It is quite common to marvel at the clever organization of ant, termite, and bee
communities. They are, of course, as much unlike ours as insects are unlike mammals, but these creatures with diminutive brains have managed to build clean and
ventilated nests, collectively forage, care for their larvae, even domesticate other insects, and survive in this way for a hundred million years. Ants, as well as other social insects, are indistinguishable and mutually replaceable within their caste. There
is no one in charge in the anthill; the queen does not rule, she just bears her progeny,
replacing short-lived worker ants. Not unlike bacteria, ants self-organize by interacting chemically, by emitting or sensing pheromones, or visually and mechanically,
when encountering other ants. These interactions are not specifically addressed, ants
distinguish their kin and nestmates from a stranger but don’t say “hello, John, nice
to see you again”: any ant in a particular colony is like any other ant. What counts,
is the frequency of encounters that provides “quorum sensing”. There is no persistent specialization. Any worker ant can carry out any work, although the response to
stimuli varies with age, and it may be possible to discern an elite of “exceptionally
active or entrepreneurial individuals” (Oster and Wilson, 1978).
Workers are mobilized for urgent tasks, be it food delivery or nest repair, and in
case of trouble either hide in the nest or attack the invader, but no one tells them
what to do, and they have to decide it independently. This calls for a sophisticated
communication language. Decisions on work allocation are taken in response to a
pattern of inputs, either attractive or repulsive, including environmental stimuli, frequency of encounters with workers busy on particular tasks, and visual and olfactory
signals. Relevant information may assume specific forms; thus, ants mark trails to
food sources using pheromones, and bees indicate them by “dancing” movements.
Processing this involves a kind of mental computation, and requires memory. The
cognitive power of an insect’s brain makes feasible what a microbe swarm could
never achieve.
Still, all actions are “robotic”; it would be quite feasible to program automata
to operate in this way. This would not need a billion euro budget of the European
Human Brain Project (Sect. 7.2). It can also be imitated by a not too complicated
mathematical model (Gordon, 1999). Moreover, cooperation is not perfectly coordinated: among a group of ants carrying a load, one can observe individuals pulling
in opposite directions.