DOI: 10.5061/dryad.6t1g1jx4p
title: Data from: Infrared camouflage in leaf-sitting frogs: A cautionary tale on adaptive convergence

description: Many green animals that appear cryptic against green leaves also match
 leaf reflectance in the near-infrared (NIR). It is unlikely that this NIR
 background matching contributes to visual camouflage because animals do
 not see NIR light. Two alternative explanations have been proposed –
  infrared camouflage (i.e. matching the temperature of the
 background) and thermoregulation – but neither hypothesis has been
 experimentally tested. To test these hypotheses, we developed coatings
 that manipulate NIR reflectance independently from visible reflectance. We
 produced agar frog models that mimic the reflectivity of different species
 of leaf-sitting frogs, which are visibly green but differ greatly in NIR
 reflectance. We compared heating rates and temperature (surface and core)
 of high and low NIR reflectance frog models in the laboratory using a
 solar simulator, and in tropical rainforest – the natural habitat of
 leaf-sitting frogs. In the laboratory, agar frog models with low
 NIR reflectance heated up more quickly and reached higher temperatures
 than those with high NIR reflectance. However, in the field, there was no
 significant difference between high and low NIR treatments in the
 similarity of surface temperature to the adjacent leaves or in core
 temperature, thus failing to support the infrared camouflage and
 thermoregulation hypotheses, respectively. The lack of difference
 between treatments is likely due to the limited exposure of frogs to
 direct solar radiation in their natural habitats. We propose a
 non-adaptive explanation for NIR background matching based on specific
 mechanisms underlying green coloration and translucence in frogs and
 caution against assuming adaptive convergence.
description: # Infrared camouflage in leaf-sitting frogs: A cautionary tale on adaptive
 convergence **File: 1_LabDataAnalysis.Rmd** Description: Compiles and
 visualizes the heating rate data collected in the lab. Also visualized the
 spectral data collected in the lab, and from the literature. Requires: *
 heatingrate_chamber.csv * heatingrate_open.csv * spectraldata.csv *
 spectraldatalinear.csv * spectraldataexp.csv * ASTMG173.csv **File:
 2_FieldDataAnalysis.Rmd** Description: Runs the analyses for the field
 data. Requires: * fielddat_ibuttoncorrelation.csv *
 fielddat_ibutton95max.csv * FLIRData.csv ## DATASETS **Data:
 heatingrate_chamber.csv** Description: Heating rate data for small frog
 models (high and low NIR reflectance) collected in the lab in a chamber
 that controls for convection and conduction. temp: Temperature (Celcius)
 from thermocouple treatment: Coating type, high (High_NIR) or low
 (Low_NIR) near infrared reflectance temp_type: Recording location, surface
 (sur_temp) or internal (in_temp) time: Actual time (hours:minutes:seconds)
 filter: Lighting condition: full spectrum (ALL), nearinfrared only (NIR)
 or UV-VIS only (UV_VIS) time_order1: Time since start of experiment in
 seconds temp_diff_withair: Difference in temperature between the model and
 air temperature (C) **Data: heatingrate_open.csv** Description: Heating
 rate data for all frog models (high and low NIR reflectance) collected
 outside of the chamber, therefore does not control for convection and
 conduction. temp: Temperature (Celcius) from thermocouple treatment:
 Coating type and size. LHNIR: Large, high NIR; LLNIR: Large, low NIR;
 SHNIR: Small, high NIR; SLNIR: Small, low NIR; LUN: Large uncoated; SUN:
 small, uncoated. temp_type: Recording location, surface (sur_temp) or
 internal (in_temp) time: Actual time (hours:minutes:seconds) filter:
 Lighting condition: full spectrum (ALL), nearinfrared only (NIR) or UV-VIS
 only (UV_VIS) time_order1: Time since start of experiment in seconds size:
 Model size, Small or Large NIRtreatment: NIR coating type: High NIR, Low
 NIR or Uncoated **Data: spectraldata.csv** Description: Reflectance data
 from our model frogs, recorded in the lab, as well as spectral data of
 real leaf sitting frogs, collected from the literature. wl: wavelength
 (nanometers) refl: reflectance as proportion (max = 1; min = 0), relative
 to a white standard. se: standard error, only for model frog measurements
 species: species name or if it is a model frog. NIR: Whether it has low or
 high NIR reflectance type: Model or Real species treatment: Combination of
 NIR classification and species classification **Data:
 spectraldatalinear.csv** Description: As above but has the linear decline
 in reflectance added for wavelengths beyond 950nm. **Data:
 spectraldataexp.csv** Description: As above but has the exponential
 decline in reflectance added for wavelengths beyond 950nm. **Data:
 ASTMG173.csv** Description: Irradiance spectrum of sunlight ASTM G-173
 Wvlgth nm: Wavelength in nanometers Global tilt W*m-2*nm-1: Irradiance in
 watts per meter squared per nanometer **Data:
 fielddat_ibuttoncorrelation.csv** Description: iButton data paired
 together based on frog pairs in the field. That is, to determine whether
 one type of frog in each pair is consistently warmer or cooler than the
 other type of frog, we have reorgansied the dataset so these temperatures
 are linked (xaxis and yaxis values). uqID: There are mulitple measurements
 for each individual frog on each day. This variable links measurements
 from the same frog on a particular day. xaxis: If Group is a coated group
 (L or S), this is the temperature of the low NIR frog. If Group is
 uncoated (U), this is the temperature of the small NIR frog. yaxis: If
 Group is a coated group (L or S), this is the temperature of the high NIR
 frog. If Group is uncoated (U), this is the temperature of the large NIR
 frog. Date.Time: Date and time from ibutton SiteID: Five sites were
 selected each day for three days (i.e. 15 sites). This variable links
 measurements from frogs at each site (one of each frog type) PairID: Model
 frogs were placed in the field in pairs. This variable links paired frog
 models. Group: For pairs were either large low and high NIR (L), small low
 and high NIR (S) or uncoated small and large (U). This variable shows
 these groupings. airtemp: Air temperature at that site at the same time as
 the model temperatures **Data: fielddat_ibutton95max.csv** Description:
 For each model for each day in the field, this dataset has the 95th
 percentile temperature. This is a proxy for the maximum temperature
 reached. SiteID: Five sites were selected each day for three days (i.e. 15
 sites). This variable links measurements from frogs at each site (one of
 each frog type) uqID: There are mulitple measurements for each individual
 frog on each day. This variable links measurements from the same frog on a
 particular day. PairID: Model frogs were placed in the field in pairs.
 This variable links paired frog models. Group: For pairs were either large
 low and high NIR (L), small low and high NIR (S) or uncoated small and
 large (U). This variable shows these groupings. NIR: Type of NIR coating,
 low NIR reflectance, high NIR reflectance or uncoated. Size: Size of frog,
 small or large iButtonID: iButtons were placed in an individual frog model
 and used for three consecutive days. This variable links measurements from
 the same iButton. max95: The is the 95th percentile (maximum) for each day
 for each frog model. maximum: This is the overall maximum temperature for
 each day for each model. max95air: This is the 95th percentile for
 airtemperature at each site. **Data: FLIRData.csv** Description: Surface
 temperature for model frogs, extracted from thermal images. Date: Date
 image was taken SiteID: Five sites were selected each day for three days
 (i.e. 15 sites). This variable links measurements from frogs at each site
 (one of each frog type) Time: whether image was taken in the morning (am)
 or afternoon (pm) PairID: Model frogs were placed in the field in pairs.
 This variable links paired frog models. Group: For pairs were either large
 low and high NIR (L), small low and high NIR (S) or uncoated small and
 large (U). This variable shows these groupings. IR.image: number of
 infrared photograph DC.image: number for colour photograph Notes: Notes
 regarding image and data extraction Delete: Data that needs to be filtered
 out (Y) or not (N) Temp_LNIR: Surface temperature (Celcius) of the low NIR
 reflectance frog Temp_HNIR: Surface temperature (Celcius) of the High NIR
 reflectance frog Temp_UCL: Surface temperature (Celcius) of the large
 uncoated frog Temp_UCS: Surface temperature (Celcius) of the large
 uncoated frog Temp_env: Surrounding environment temperature (i.e. leaf
 temperature)