Citation
Willink, Beatriz; Brenes-Mora, Esteban; Bolaños, Federico; Pröhl, Heike (2013), Data from: Not everything is black and white: color and behavioral variation reveal a continuum between cryptic and aposematic strategies in a polymorphic poison frog, Dryad, Dataset, https://doi.org/10.5061/dryad.43534
Aposematism and crypsis are often viewed as two extremes of a continuum of visual conspicuousness to predators. Theory predicts that behavioral and coloration conspicuousness should vary in tandem along the conspicuousness spectrum for antipredator strategies to be effective. Here we used visual modeling of contrast and behavioral observations to examine the conspicuousness of four populations of the granular poison frog, Oophaga granulifera, which exhibits almost continuous variation in dorsal color. The patterns of geographic variation in color, visual contrast, and behavior support a gradient of overall conspicuousness along the distribution of O. granulifera. Red and green populations, at the extremes of the color distribution, differ in all elements of color, contrast, and behavior, strongly reflecting aposematic and cryptic strategies. However, there is no smooth cline in any elements of behavior or coloration between the two extremes. Instead populations of intermediate colors attain intermediate conspicuousness by displaying different combinations of aposematic and cryptic traits. We argue that coloration divergence among populations may be linked to the evolution of a gradient of strategies to balance the costs of detection by predators and the benefits of learned aversion.
Reflectance&irradiance
Data collected by Beatriz Willink and Esteban-Brenes Mora. Date of collection: 20110701-20111112. No missing data. Data includes the mean reflectance of the dorsal and ventral skin of 99 frogs, the mean reflectance of each category of background substrates,at each population, and the mean irradiance at each population. See METHODS for details. Reflectance is a percentage of light. Units for irradiance are uW/m^2. In column headers, numbers show the frog ID. The color phenotype of each frog is included in the file Frog_color&contrast.csv
Frog_color&contrast
Data collected and prepared by Beatriz Willink, Esteban Brenes-Mora, Heike Pröhl. Date of collection: 20110701-20111112. No missing data. Data includes measures of color and visual contrasts (as seen by a model bird viewer) for the dorsal and ventral skin of frogs. Contrasts were calculated against natural backgrounds and with the local irradiance (see METHODS). Calculations for color elements (Qt, Hue and Chroma) are given in Endler. 1993. Biol. J. Linn. Soc 41:315-352. Calculations for contrasts are given in Appendix 1 of Pröhl and Ostrowski. 2011. Evol Ecol 25:993-1015. Qt is the sum of reflected light across all 1 nm intervals between 400-700 nm. Chroma and Hue are objective color color space measures. Chroma is the Euclidean distance from the origin of color space to the reflectance spectra. Hue is the angle clockwise from the axis defined by the long-wavelentgh segment of the spectra (Red). Units for contrasts are jnd (just noticeable differences). In column headers, CC means Color (chromatic) contrast and BC is brightness (achromatic) contrast. TR refers to contrasts calculated against trunks (all types of tree bark), MR refers to contrasts calculated against rocks, usually covered with moss, GL indicates contrasts calculated against green leaves and LL indicates contrasts calculated against leaf-litter
Focal_male_behavior
Data collected by Beatriz Willink during 20110613-20111112. No missing data. Behavioral data of focal males. Calling_time_no_fem is the total time (in seconds) a male was observed calling during all observations in which there were no females nearby. Quiet_time_no_fem is the total time (in seconds) a male was observed NOT calling during all observations in which there were no females nearby. Feeding_events is the number of feeding events in 150 min for each male. Movement is the number of minutes (out of 150) in which frogs moved over a distance of more than 5 cm. No_movement is the number of minutes (out of 150) in whichs frogs did not move. Inactivity_time is the number of minutes (out of 150) in which frogs did not move, forage or call, but were sitting still. Activity_time is the number of minutes (out of 150) in which frogs performed at least one conspicuous behavior, calling, moving or foraging. Calling_exposure is the average exposure at a distance of 1 m (and weighed by the time spent at all calling positions) of a frog's body while calling. See METHODS for details.
Escape_behavior
Data collected by Beatriz Willink during 20110805-20111112. No missing data. Data is the flight initiation distance (FID) in cm from an approaching bird dummy.
