Meeting Abstract
Differences in morphology between closely related species are known to impact function and consequently affect organismal performance. The diverse hyobranchial apparatus morphologies of salamanders enable varying degrees of tongue projection performance during terrestrial prey capture. Many plethodontid salamanders possess a specialized morphology and employ elastic mechanisms to achieve high-power tongue projection. The salamandrid salamanders Salamandra salamandra and Chioglossa lusitanica are also specialized terrestrial feeders. Chioglossa, however, possesses an extreme hyobranchial morphology similar to plethodontids, suggesting that it may approach the tongue projection performance of plethodontids. High-speed imaging (3000 Hz), in conjunction with kinematic and inverse dynamic analyses, reveals that feeding performance is increased in Chioglossa relative to Salamandra. Relative maximum tongue-projection distance is 1.4 times greater in Chioglossa, and maximum tongue-projection velocity, acceleration, and muscle-specific power are 10, 40, and 400 times greater, respectively. The high muscle-mass-specific power of Chioglossa is comparable to that estimated in plethodontid salamanders with elastic projection. These results reveal an elastic tongue-projection mechanism in Chioglossa that likely evolved independently of that of plethodontids.
