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Regardless of viscosity, several aspects of lungfish swimming were similar to those of other swimming vertebrates including: posteriorly propagated muscle activity that was unilateral and alternated between the left and right sides at each longitudinal location, and posterior increases in the amount of bending, the amplitude of muscle activity and the timing differences between muscle activity and bending. With increased viscosity (1\u20131000 cSt),significant increases occurred in the amount of lateral bending of the vertebral column and the amplitude of muscle activity, particularly in the most anterior sites, but the distance the fish traveled per tail beat decreased. The magnitude of the phase shift between EMG onset relative to bending increased by as much as 13% of a cycle with increased viscosity, so that the muscles were increasingly active during lengthening rather than shortening. Therefore, with increased viscosity the relationship between axial muscle activity and bending in the lungfish became more dissimilar rather than converging on the motor pattern used by other ectothermic vertebrates when undulating in fully terrestrial environments.<\/jats:p>","DOI":"10.1242\/jeb.013029","type":"journal-article","created":{"date-parts":[[2008,5,4]],"date-time":"2008-05-04T04:50:54Z","timestamp":1209876654000},"page":"1612-1622","source":"Crossref","is-referenced-by-count":54,"title":["The effects of viscosity on the axial motor pattern and kinematics of the African lungfish (<i>Protopterus annectens<\/i>) during lateral undulatory swimming"],"prefix":"10.1242","volume":"211","author":[{"given":"Angela M.","family":"Horner","sequence":"first","affiliation":[{"name":"Department of Biological Sciences, University of Cincinnati, PO Box 210006, Cincinnati, OH 45221-0006, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruce C.","family":"Jayne","sequence":"additional","affiliation":[{"name":"Department of Biological Sciences, University of Cincinnati, PO Box 210006, Cincinnati, OH 45221-0006, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"237","reference":[{"key":"2021042511181486400_REF1","doi-asserted-by":"crossref","unstructured":"Altringham, J. 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