Mechanics of Righting Behavior in the Tarantula (Theraphosidae)

The ability for an organism to right itself (correcting the orientation of its body when overturned) in its environment is crucial to survival. Righting behavior can vary widely among taxa, and is largely based on body morphology. Tarantula righting behavior is not only needed in critical situations (falling and landing upside down), but is necessary after molting, when the tarantula must intentionally turn itself upside down in order to shed the old cuticle. In order to describe and analyze the mechanics of this behavior, 33 external markers were painted on leg joints and abdomen. Two species of tarantula, Grammostola rosea and Aphonopelma sp., were filmed with four spatially calibrated, and time-synchronized, high speed video cameras. Righting behavior was digitized in Matlab to create a 3D model for visualization and analysis. We observed a stereotypical sequence of behaviors within each species used to rotate the body into the prone position. In all species, the third and fourth pair of legs are initially used to lever the cephalothorax off of the substrate. Aphonopelma rotates the prosoma primarily with the tarsus of the right second and third legs, while G. rosea uses the patella of the right third leg to rotate the prosoma. The efficiency with which tarantulas conduct this stereotypical behavior displays how such morphologically complex organisms can have an extraordinary amount of control when moving their bodies

Grantor dc:publisher

Wake Forest University

Year dc:date.issued

2018

Author dc:creator

• ODonnell, Dan John

• 3D digitizing

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10339/90769

OAI identifier oai:identifier

oai:wakespace.lib.wfu.edu:10339/90769