(Downloading may take up to 30 seconds.
If the slide opens in your browser, select File -> Save As to save it.)
Click on image to view larger version.

Fig. 2. Experimental tests and measures. (A) Response of a subordinate crayfish
separated from its dominant partner by an opaque divider. (Ai) Before the
stimulus touch. (Aii) After the touch; the animal has turned to face the
source of the touch. (B) Response of a subordinate in the presence of its
dominant partner. (Bi) Before the stimulus touch. (Bii) After the touch, the
animal moved forward away from the touch site. (C,D) Diagrams describing
measurements of the HP distance and the angle
values in orienting and
avoidance responses. The open crayfish outline shows the position of the
animal before stimulus; the gray crayfish shows the position of the animal
after stimulus. The HP distance is the distance from the head (H) to the point
of probe contact (P).
is the angle between the body axis and the HP
line segment. (C) Orienting responses. (Ci) Both
and HP are small when
an animal pivots backwards to face the probe. (Cii)
is large and HP is
small when an animal turns and advances past the probe. (D) Avoidance
responses. (Di)
becomes small and HP becomes large when an animal
walks backwards away from the probe. (Dii)
and HP both become large
when an animal walks forward away from the probe.