The behavioral responses of amphibians and reptiles to microgravity on parabolic flights

Department of Anatomy & Neurobiology, Sir Charles Tupper Medical Building, Dalhousie University, Halifax, Nova Scotia, Canada B3H 1X5.
Zoology (Impact Factor: 1.67). 02/2005; 108(2):107-20. DOI: 10.1016/j.zool.2005.03.001
Source: PubMed


In the present study, we exposed 53 animals from 23 different species of amphibians and reptiles to microgravity (mug). This nearly doubles the number of amphibians and reptiles observed so far in mug. The animals were flown on a parabolic flight, which provided 20-25s of mug, to better characterize behavioral reactions to abrupt exposure to mug. Highly fossorial limbless caecilians and amphisbaenians showed relatively limited movement in mug. Limbed quadrupedal reptiles that were non-arboreal in the genera Leiocephalus, Anolis, and Scincella showed the typical righting response and enormous amounts of body motion and tail rotation, which we interpreted as both righting responses and futile actions to grasp the substrate. Both arboreal and non-arboreal geckos in the genera Uroplatus, Palmatogecko, Stenodactylus, Tarentola, and Eublepharis instead showed a skydiving posture previously reported for highly arboreal anurans. Some snakes, in the genera Thamnophis and Elaphe, which typically thrashed and rolled in mug, managed to knot their own bodies with their tails and immediately became quiescent. This suggests that these reptiles gave stable physical contact, which would indicate that they were not falling, primacy over vestibular input that indicated that they were in freefall. The fact that they became quiet upon self-embrace further suggests a failure to distinguish self from non-self. The patterns of behavior seen in amphibians and reptiles in mug can be explained in light of their normal ecology and taxonomic relations.

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Available from: Richard Wassersug
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    • "But recent data from Bob Full's lab at the University of California, Berkeley, has revealed that, like primates, airborne lizards are likely to use their tails for in-air stabilization and body reorientation. Before 2008, occasional reference was made to the fact that lizards use their tails in midair to influence body movements (e.g., Higham et al. 2001; Young et al. 2002; Wassersug et al. 2005). But in a series of articles over the past several years, Jusufi et al. (2008) (2010) (2011) and Libby et al. (2012) have used evidence from experiments as well as physical and mathematical models to clearly identify the importance of the lizard tail as an in-air stabilizer. "
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