Anemomenotaktische Orientierung bei Skorpionen (Chelicerata, Scorpiones)

Summary

• 1. Scorpions can orient menotactically to horizontal air currents (Fig. 1).

• 2. Changing the wind velocity from 0,05–0,1 m/sec to 3–5 m/sec has no influence on the menotactic angle kept by an anemomenotactic oriented scorpion (Fig. 2).

• 3. The receptors percieving the direction of air currents are the trichobothria.

• 4. Orientation to horizon landmarks, anemomenotactic and astromenotactic orientation does not exclude each other but complete themthelves mutually:

• a) A scorpion orienting to horizon landmarks learns the corresponding anemomenotactic and astromenotactic angle (Fig. 4).

• b) While orienting anemomenotactically (which is normally the main means of orientation when landmarks are absent) they continously learn new astromenotactical angles (Fig. 5), thus compensating for the movement of the moon or sun which can not be compensated otherwise.

• c) Short calms and short changes of wind direction can be overcome by astrotaxis.