Data from: Form-function relationships within species are uncoupled from those across species in swimming and jumping performance in arboreal frogs

Description

Notes

Methods

Specimens and species

We collected 40 individuals of Hyla cinerea (eight females and 32 males) at Red Slough Wildlife Management Area (Oklahoma, USA) on June 24, 2023. Hyla cinerea is a hylid frog generally found during the breeding season on emergent vegetation in large, still water bodies (Dodd, 2023).  Males were identified by the presence of nuptial pads and a distended throat sac, whereas females lacked these features; sex was verified by internal inspection of the gonads after we completed all work with live animals. This research was conducted under Oklahoma State University IACUC protocol 20-09 and Oklahoma Department of Wildlife Conservation scientific collecting permit W2302.

The additional interspecific data from 38 arboreal and four semi-arboreal species (n = 177; 1–8 individuals per species) were obtained from previously published data (Moen et al., 2013, 2021a, b). These species have a common ancestor estimated at 114.9 million years old, and they belong to five different families: Mantellidae (n = 19 species), Hylidae (n = 14), Microhylidae (n = 5), Hyperoliidae (n = 2), and Rhacophoridae (n = 2).

Jumping and swimming trials

All specimens were measured for jumping and swimming performance by using a high-speed camera. All details of performance trials, video capture, and video processing followed Moen et al. (2013; 2021) and can be found in those papers. In brief, individuals performed both behaviors in several trials on different days, such that we could maximize our chance to collect the peak performance in both behaviors for each individual. Jumping take-off and burst swimming were recorded using high-speed cameras at 250 frames-per-second. We then extracted peak acceleration (m²/s) and peak velocity (m/s) for both performances per individual.

Morphological measurements

We collected five linear measurements on all preserved specimens using a digital caliper: femur length, tibiofibula length, tarsus length, and foot length on the left hindlimb, plus snout-to-vent length (SVL). We summed the hindlimb bone lengths to calculate total leg length, which is relevant to both jumping and swimming performance (Moen 2019). We also photographed the left foot pressed against a glass slide, then measured foot webbing areas between all digits and foot area (without webbing) in ImageJ (version 1.53e, Schneider et al., 2012). We summed these area measurements to calculate total foot area, which should be relevant to swimming performance (Gal & Blake, 1988; Nauwelaerts et al., 2001; Richards, 2008, 2010). Finally, we dissected out all upper- and lower-leg muscles of the left hindlimb, removed excess surface ethanol by patting them dry, and weighed them on a scale with 0.0001g precision. We then added all the muscle weights to calculate total leg muscle mass. These hindlimb muscles contain the major extensors relevant for jumping and swimming (Gillis & Biewener, 2000; James & Wilson, 2008; Nauwelaerts et al., 2007; Olson & Marsh, 1998; Prikryl et al., 2009), and their summed mass has been shown to strongly correlate with performance in both behaviors across frog species (Moen et al. 2013; Moen 2019).