Stepping Patterns in Tarantula Spiders
نویسنده
چکیده
The limb movements of many multilegged animals occur in metachronal sequences, often sequences running from posterior to anterior. Such sequences are not so conspicuous in animals with few legs. However, for the walking of certain insects with variable gaits it has been possible to produce a descriptive model based on metachronal rhythms with stepping pattern varying with frequency (Wilson, 1966 a). This same model can be extended to animals with four (or more) pairs of legs. For simplicity one can assume that legs on opposite sides of the animal always alternate and then make the following formulation for legs of one side. Number the legs 1, 2, 3, and 4, from front to back. Then the basic stepping sequence in the model is 4321. Again for simplicity, hold the interval between 4 and 3, 3 and 2, and 2 and 1 constant. Vary the repetition rate of the whole set. At low repetition rates the stepping pattern is
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