Continuous variation in an aposematic pattern affects background contrast, but is not associated with differences in microhabitat use

Variation in aposematic signals was once predicted to be rare, yet in recent years it has become increasingly well-documented. Despite increases in the frequency with which polytypism and polymorphism have been suggested to occur, population-wide variance is rarely quantified. We comprehensively sampled a subpopulation of the poison frog Oophaga sylvatica, a species which is polytypic across its distribution and also shows considerable within-population polymorphism. On one hand, color pattern polymorphism could be the result of multifarious selection acting to balance different signaling functions and leading to the evolution of discrete sub-morphs which occupy different fitness peaks. Alternatively, variance could simply be due to relaxed selection, where variation would be predicted to be continuous. We used visual modeling of conspecific and heterospecific observers to quantify the extent of within-population phenotypic variation and assess whether this variation produced distinct s..., In March 2020, we photographed 35 Oophaga sylvatica (Perla morph) at the private forest reserve ‘Bosque Protector la Perla’ near La Concordia, Ecuador. This represented a comprehensive survey of every individual observed in the area by a team of five experienced observers, over two days. The Perla morph is approximately 26 mm in length and is predominantly black with a red pattern that varies from small spots to larger irregular blotches, to whole patches of homogenous color. Previous work suggests that the frogs' colors have very high internal and external contrast, and that UV reflectance is minimal both from the frogs and their natural leaf litter background (Yeager and Barnett 2020).
We photographed each frog within the microhabitat where it was first observed, following methods detailed in Yeager and Barnett (2020), Yeager and Barnett (2021). In brief, each image was taken using a quartz converted UV sensitive Canon EOS 7D camera combined with a metal body NIKKOR EL 80 mm lens. As ..., , # Data from: Continuous variation in an aposematic pattern affects background contrast, but is not associated with differences in microhabitat use

Data used in:

Yeager & Barnett.\
Can continuous variation in a polymorphic aposematic signal represent an adaptive benefit?\
Justin Yeager & James B. Barnett

For further information contact:

Justin Yeager\
Email:

## Description of the data and file structure

### ## ==== INTERNAL CONTRAST DATA - K-MEANS & CLUSTER ANALYSIS ====

Data files:

* 01_InternalContrast_Bird.txt internal chromatic & achromatic contrast, & pattern energy from the blue tit (bird) visual model

* 02_InternalContrast_Snake.txt internal chromatic & achromatic contrast, & pattern energy from the coachwhip (snake) visual model

* 03_InternalContrast_Frog.txt internal chromatic & achromatic contrast, & pattern energy from the O. pumilio (frog) visual model

Format: tab-delimited text

Column identification:

* visual_mod...

警戒信号（aposematic signals）的变异曾被学界预测为极为罕见，但近年来相关记录正日益增多。尽管愈发频繁地有研究提出多型种（polytypism）与多态现象（polymorphism）的存在，种群水平的变异仍极少被量化。我们对毒蛙林氏箭毒蛙（Oophaga sylvatica）的一个亚种群开展了全面采样：该物种在其整个分布范围内均呈现多型性，且种群内部亦存在显著的多态现象。一方面，体色图案多态可能源于多重选择压力的共同作用——这些选择压力平衡了不同的信号功能，最终演化出占据不同适合度峰值的离散亚形态。另一方面，种群变异也可能仅源自选择压力松弛，此时变异理应呈现连续分布。我们通过针对同种与异种观测者的视觉建模，量化了种群内部的表型变异程度，并评估该变异是否产生了显著的[原文截断]。

2020年3月，我们在厄瓜多尔拉孔科迪亚附近的私人森林保护区"Bosque Protector la Perla"内，拍摄了35只林氏箭毒蛙佩拉形态（Perla morph）个体。本次调查由5名经验丰富的观测者组成团队，耗时两天对该区域内所有可见个体开展了全面普查。佩拉形态个体体长约26毫米，体色以黑色为主，搭配红色斑纹：斑纹形态多样，可从细小斑点、不规则大块斑块直至整片均匀分布的红色区域。既往研究表明，该种箭毒蛙的体色具有极高的内部与外部对比度，且蛙体及其自然生境的枯落物背景均极少反射紫外线（Yeager与Barnett, 2020）。

我们遵循Yeager与Barnett（2020、2021）中详述的方法，在个体首次被观测到的微生境中完成拍摄。简言之，本研究采用经石英改装的紫外敏感佳能EOS 7D（Canon EOS 7D）相机，搭配金属机身尼克尔EL 80mm镜头（NIKKOR EL 80 mm lens）拍摄每一张照片。[原文截断]，# 数据来源：警戒图案的连续变异影响背景对比度，但与微生境利用差异无关

所用数据源自：
Yeager与Barnett
《多态警戒信号的连续变异能否带来适应性收益？》
贾斯汀·耶格（Justin Yeager）与詹姆斯·B·巴尼特（James B. Barnett）

如需进一步咨询，请联系：
贾斯汀·耶格
电子邮箱：

## 数据与文件结构说明
==== 内部对比度数据——K均值与聚类分析 ====

数据文件：
* 01_InternalContrast_Bird.txt：蓝山雀（blue tit）视觉模型下的内部色对比、非色对比与图案能量值
* 02_InternalContrast_Snake.txt：鞭蛇（coachwhip）视觉模型下的内部色对比、非色对比与图案能量值
* 03_InternalContrast_Frog.txt：红点箭毒蛙（Oophaga pumilio）视觉模型下的内部色对比、非色对比与图案能量值

文件格式：制表符分隔文本文件
列标识：
* visual_mod... [原文截断]