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3.3 Coordination and Control of Behaviors
(fixed-action patterns) in orienting itself to the last sensed location of a food
source (taxis) when it loses sight of it.
The tight coupling of action and perception can often be quantified by
mathematical expressions. An example of this is orienting in angelfish. In
IDIOTHETIC order to swim upright, an angelfish uses an internal (idiothetic) sense of grav-
ALLOTHETIC ity combined with its vision sense (allothetic) to see the external percept of
the horizon line of the water to swim upright. If the fish is put in a tank with
prisms that make the horizon line appear at an angle, the angelfish will swim
cockeyed. On closer inspection, the angle that the angelfish swims at is the
vector sum of the vector parallel to gravity with the vector perpendicular to
the perceived horizon line! The ability to quantify animal behavior suggests
that computer programs can be written which do likewise.

3.3 Coordination and Control of Behaviors

KONRAD LORENZ Konrad Lorenz and Niko Tinbergen were the founding fathers of ethology.
NIKO TINBERGEN Each man independently became fascinated not only with individual behav-
iors of animals, but how animals acquired behaviors and selected or coordi-
nated sets of behaviors. Their work provides some insight into four different
ways an animal might acquire and organize behaviors. Lorenz and Tinber-
gen’s work also helps with a computational theory Level 2 understanding of
how to make a process out of behaviors.
The four ways to acquire a behavior are:

INNATE 1. to be born with a behavior (innate). An example is the feeding behavior in
baby arctic terns. Arctic terns, as the name implies, live in the Arctic where
the terrain is largely shades of black and white. However, the Arctic tern
has a bright reddish beak. When babies are hatched and are hungry, they
peck at the beak of their parents. The pecking triggers a regurgitation
reflex in the parent, who literally coughs up food for the babies to eat. It
turns out that the babies do not recognize their parents, per se. Instead,
they are born with a behavior that says: if hungry, peck at the largest red
blob you see. Notice that the only red blobs in the field of vision should
be the beaks of adult Arctic terns. The largest blob should be the nearest
parent (the closer objects are, the bigger they appear). This is a simple,
effective, and computationally inexpensive strategy.

SEQUENCE OF INNATE 2. to be born with a sequence of innate behaviors. The animal is born with a
BEHAVIORS sequence of behaviors. An example is the mating cycle in digger wasps.