First published online January 17, 2007
Journal of Experimental Biology 210, 375-382 (2007)
Published by The Company of Biologists 2007
doi: 10.1242/jeb.02674
Hair plate mechanoreceptors associated with body segments are not necessary for three-dimensional path integration in desert ants, Cataglyphis fortis
Matthias Wittlinger1,*,
Harald Wolf1 and
Rüdiger Wehner2
1 Department of Neurobiology, University of Ulm, Albert-Einstein-Allee 11,
D-89069 Ulm, Germany
2 Institute of Zoology, University of Zürich, Winterthurerstrasse 190,
CH-8057 Zürich, Switzerland

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Fig. 1. Manipulated hair plates. (A) Schematic drawing of a Cataglyphis
worker ant, lateral view. The positions of the manipulated hair plates are
indicated (red rectangles); (a) neck joint, (b) alitrunkpetiole joint,
(c) petiolegaster joint. Drawing adapted from
(Wehner, 1983 ). (B) Scanning
electron micrograph (SEM) of the petiolegaster joint; ventral view.
Hair plates are in the centre of the image, not manipulated. (C) SEM of the
petiolegaster joint, ventral view; the hair plates had been shaved with
a razor splinter (one of the experimental animals that contributed to the data
in Fig. 4B).
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Fig. 2. Immobilisation of body parts. (A) Body posture in walking ants,
Cataglyphis fortis. (B) Animal with its head fixed to the alitrunk.
(C) Gaster (metasoma) fixed to the alitrunk in a prolate position of
approximately 180°. (D) Gaster fixed onto the alitrunk in an erect
(<90°) position. Drawing adapted from
(Wehner, 1983 ).
Beeswaxresin glue indicated in red.
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Fig. 3. Experimental situation and channel layout. (A) Channel cross section; (B)
single channel segment for hill training; (C) hill training and flat training
channels; (D) test channel. The search behaviour exhibited by Cataglyphis
fortis foragers after having run off their home vector is illustrated
schematically below the test channel (search trajectory). Not drawn to
scale.
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Fig. 4. Training across the artificial hill set-up (compare
Fig. 3C), experimental data I
(shaving). The top panels show search density plots (abscissae, homing
distances; ordinates, cumulated relative search densities between the first
and sixth turning points; see Materials and methods). The bottom diagrams
display box-and-whisker plots (medians of the initial six turning points),
derived from the same data sets (N=1520 ants for each
experimental situation). 00, 01 and 11 are double-digit
codes for the particular test situation, the first digit represents the
outbound run and the second digit represents the homebound run; 0 denotes the
normal situation, 1 denotes the manipulated condition. (A) Animals with the
hair plates in their neck region shaved. (B) Animals with the hair plates in
the petiolegaster region shaved. (C) Animals with both neck and
petiolegaster regions shaved.
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Fig. 5. Training across the flat channel set-up, experimental data I (A,B) and II
(C). Diagrams and details of presentation are the same as described in
Fig. 4. (A) Animals with the
hair plates in their neck region shaved. (B) Animals with the hair plates in
their petiolegaster region shaved. (C) Animals with their gaster fixed
in an erect (<90°) position.
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Fig. 6. Training across the artificial hill set-up, experimental data II
(immobilisation). Diagrams and details of presentation are the same as
described in the legend of Fig.
4. (A) Animals with their gaster fixed in a prolate
( 180°) position. (B) Animals with their head fixed in a normal
position. (C) Animals with their gaster fixed in an erect (<90°)
position.
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© The Company of Biologists Ltd 2007