Clinging performance on natural substrates predicts habitat use in anoles and geckos
Data files
Sep 10, 2021 version files 597.93 KB
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clinging_data_2021-08-05.csv
40.04 KB
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perch_use_2021-08-05.xlsx
554.26 KB
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toepad_morphology_2021-08-05.csv
3.62 KB
Abstract
1. For arboreal lizards, the ability to cling or adhere to the substrate is critical for locomotion during prey capture, predator escape, thermoregulation, and social interactions. Thus, selection on traits related to clinging is likely strong.
2. Correlations between morphology, performance, and habitat use have been documented in arboreal lizards, providing a framework for using functional traits to predict habitat use in the field.
3. We tested the hypothesis that clinging performance predicts habitat use in an actively assembling community of introduced lizards in Hawaiʻi comprised of anoles (Anolis carolinensis, A. sagrei) and day geckos (Phelsuma laticauda).
4. We measured morphological traits (toepad area and lamellae number) and tested clinging performance on two artificial and eight natural substrates in the lab. We measured habitat use in 10 m x 10 m outdoor enclosures where habitat availability was controlled and the lizard species assemblage was manipulated to reflect all species combinations. The enclosure experiment generated more than 9,000 habitat use observations from 360 lizards.
5. Morphological traits that predict performance in Anolis were not predictive in Phelsuma, indicating that direct measures of performance are necessary for comparisons between the genera.
6. Measuring clinging performance on multiple substrates provided key insights into patterns of habitat use. While all three species performed best on an artificial smooth substrate (acrylic), performance on natural substrates predicted which texture (rough vs. smooth) was most often used by each species.
7. Performance predicted perch height use: species with the greatest clinging performance (A. carolinensis and P. laticauda) across substrates perched twice as high as A. sagrei.
8. We did not observe habitat shifts in the height or texture of perches used by any species in response to experimental manipulation of the lizard species assemblage.
9. Our results highlight the inextricable link between ecology, morphology, and performance, the importance of measuring functional traits in ecologically-relevant ways, and the potential for resource partitioning to be influenced by differences in the ability to attach to different substrates.
See the manuscript.
Metadata describing each column of the file "clinging data 2021-08-05.csv"
ID: unique id for each individual
sex: f = female; m = male
substrate: different substrates used to test clinging performance
max.force.per.mass = maximum force in Newtons to dislodge a lizard clinging with one foot from the substrate dividided by lizard mass in kg.
texture: smooth substrate vs. rough substrate
species: ACAR = Anolis carolinensis, ASAG = Anolis sagrei, PLAT = Phelsuma laticauda
year: data were collected in two different years, 2016 and 2019
type: substrate type, whether artificial (acrylic, sandpaper) or natural (all others)
Metadata describing each column of the file "toepad morphology 2021-08-05.csv"
ID: specimen ID number from the Bernice Pauahi Bishop Museum in Honolulu, HI
species: ACAR = Anolis carolinensis, ASAG = Anolis sagrei, PLAT = Phelsuma laticauda
sex: male vs female
SVLmm: snout-vent-length in mm
meanArea: mean toepad area of the 4th toe on the hindfeet in mm2. Average is calculated as (area of toepad of 4th toe on left hind foot + area of toepad of 4th toe on right hindfoot)/2. The 4th toe is the longest toe on the hindfoot in A. sagrei and A. carolinensis.
meanLam: mean number of lamellae (i.e. undivided scales) on the 4th toe on the hindfeet. Average is calculated as (number of lamellae on 4th toe on left hind foot + number of lamalle on 4th toe on right hindfoot)/2. The 4th toe is the longest toe on the hindfoot in A. sagrei and A. carolinensis.
Metadata describing each column of the file "perch use 2021-08-05.csv"
species: ACAR = Anolis carolinensis, ASAG = Anolis sagrei, PLAT = Phelsuma laticauda
sex: F = female, M = male
svl: snout-vent length upon initial capture, measured in mm. Measure of body size.
lizID: unique identifier for each individual lizard.
PHcm: perch height in centimeters. How high off the ground was the lizard perching when first seen undisturbed? Perch heights of zero indicate animal was on the ground.
PT: perch type. What was the lizard perching on?
viewType: scan = lizard observation was recorded during a standardized scan where similar effort was applied to all plots (i.e. a "snapshot" of all lizards in all plots). incidental = lizard observation was recorded opportunistically (i.e. without controlling effort).
plot: There are seven enclosures and each was identified by a number, e.g. plot 1 is the first enclosure.
rep: Replicate. The study was replicated six times using the same seven enclosures.
plotRep: factor to indicate combined plot and replicate.
treatment: lizard assemblage. plat = Phelsuma laticauda; acar = Anolis carolinensis; asag = Anolis sagrei; acar-plat = Phelsuma laticauda + Anolis carolinensis; asag-plat = Phelsuma laticauda + Anolis sagrei; acar-asag = Anolis carolinensis + Anolis sagrei; acar-asag-plat = Anolis carolinensis + Anolis sagrei + Phelsuma laticauda
texture: texture of the perch the lizard was seen on, smooth vs. rough. NA