The tactile‐stimulated startle response of tadpoles: acceleration performance and its relationship to the anatomy of wood frog (Rana sylvatica), bullfrog (Rana catesbeiana), and American toad (Bufo americanus) tadpoles

Abstract

I described the tactile-stimulated startle response (TSR) of wood frog (Rana sylvatica), bullfrog (Rana catesbeiana), and American toad (Bufo americanus) tadpoles. One purpose was to rank species in terms of maximum acceleration performance. Also, I tested whether anatomical indicators of performance potential were predictive of realized performance. TSRs were elicited in a laboratory setting, filmed at 250 Hz, and digitally analyzed. TSRs began with two, initial body curls during which tadpoles showed a broad spectrum of movement patterns. TSR performance was quantified by maximum linear acceleration and maximum rotational acceleration of the head/body, both of which tended to occur immediately upon initiation of motion (< 0.012 sec into the response). Bullfrog tadpoles had higher maximum acceleration than the other species, but other interspecific differences were not significant. The species' rank order for the anatomical indicator of linear acceleration potential was bullfrog > wood frog > American toad. The species' rank order for the anatomical indicator of rotational acceleration potential was bullfrog > wood frog = American toad. Thus, the anatomical indicators roughly predicted the rank order of interspecific average performance. However, the anatomical indicators did not correlate with individual tadpole performance. Variability in behavioral patterns may obscure the connection between anatomy and performance. This is seen in the current lack of intraspecific correlation between a morphological indicator of acceleration capacity and acceleration performance.

Unraveling the relative contribution of inter‐ and intrapopulation functional variability in wild populations of a tadpole species

“…In the present study, tadpoles from Mangkang population were the most functionally different individuals compare to others, which had higher trunk bending shape values, lower eye position values, and lower spiracle position values. These functional traits were more related to locomotion, indicating that the locomotion of these individuals was small magnitude of vertebral curvature but more endurance (i.e., some dorso‐ventral flexion, but little lateral flexion; Eidietis, ; Azizi et al., ). This probably because these individuals were sampled from the water bodies of Jinsha and Lancang rivers sutures that can have relative higher flow velocity.…”

“…Based on the criteria that functional traits should be easily quantified on a large number of individuals (Dumay, Tari, Tomasini, & Mouillot, ), and on the basis of published literatures (Azizi, Landberg, & Wassersug, ; Eidietis, ; Grosjean, Randrianiaina, Strauß, & Vences, ; Grosjean, Strauß, et al., ; Raharivololoniaina, Grosjean, Raminosoa, Glaw, & Vences, ; Strauß et al., ; Van Buskirk & McCollum, ), nine complementary functional traits were selected to reflect the main ecological functions of tadpoles in freshwater ecosystems. These traits include total length (TL), body length (BL), body maximum height (BMH), body maximum width (BMW), tail length (TAL), tail muscle width (TMW), tail muscle height (TMH), oral disk width (OD), interocular distance (IO), and distance from tip of snout to opening of spiracle (SS; Figure ; Glos, Teschke, and Vences (); Fei et al., ; Aguayo, Lavilla, Vera Candioti, & Camacho, ; Baldo, Maneyro, & Laufer, ; Grosjean, Strauß, et al., ).…”

Natural variation in morphology of larval amphibians: Phenotypic plasticity in nature?

“…The functional consequences of variation in tail shape are not fully understood. Relationships between tail depth and swimming speed or acceleration can be positive Leimberger 1997, Dayton et al 2005), but are usually negative or absent (Van Buskirk and McCollum 2000a, b, Richardson 2002, Teplitsky et al 2005, Eidietis 2006, Johnson et al 2008. On the other hand, a large and conspicuous tail fin attracts predator attacks away from the vulnerable head/body region, so the deep tail may improve predator escape by functioning as a lure .…”

Effects of Tail Clipping on Larval Performance and Tail Regeneration Rates in the Near Eastern Fire Salamander, Salamandra infraimmaculata

“…Few studies exist that assess the fitness effect of a truncated tail in urodele aquatic larval stages [27,28,29] and patterns seen in anurans may not necessarily be extrapolated to urodeles for several reasons. The kinematic patterns of swimming differ between urodele larvae and anuran tadpole [16,30]. Consequently damage to the tail tissues may affect locomotor abilities differently between the two orders.…”