10.5061/DRYAD.KS53J
de Zwaan, Devin R.
University of British Columbia
Greenwood, Jennifer L.
University of British Columbia
Martin, Kathy
University of British Columbia
Data from: Feather melanin and micro-structure variation in dark-eyed
junco (Junco hyemalis) across an elevational gradient in the Selkirk
Mountains
Dryad
dataset
2016
pheomelanin
Junco hyemalis
2016-09-22T19:35:15Z
2016-09-22T19:35:15Z
en
https://doi.org/10.1111/jav.01050
58714 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Variation in feather melanism and microstructure can arise through sexual
selection and ecological functional drivers. Melanin-based plumage traits
are associated with sexual dichromatism and the intensity of sexual
selection in many avian species, but also have several ecological benefits
such as protection against ultra-violet (UV) radiation, camouflage, and
feather strength. Additionally, feather microstructure influences
thermoregulation. Plumage variation across species is well documented;
however, the relative role of sexual selection and ecological drivers in
intra-specific and within-population variation is less established. We
investigated UV reflectance, melanism, and feather microstructure in a
population of Oregon dark-eyed juncos Junco hyemalis oreganus between high
(1900–2200 m a.s.l.) and low (450–800 m a.s.l.) elevations in the Selkirk
Mountains to evaluate potential sexual selection and ecological drivers of
variation. We found no difference in UV reflectance or lightness
(melanism) of head feathers between elevations, but individuals at high
elevation had lighter (less melanism) and less brown (less pheomelanin)
body contour feathers than at low elevations. High elevation individuals
also had longer contour feathers with more pronounced plumulaceous
regions. Sexual dichromatism did not vary between elevations, leading us
to reject sexual selection in favour of ecological functional drivers of
plumage variation in this system. To our knowledge, this is the first
study to identify within-population differences in feather melanism and
microstructure between different elevations.
Plumage colour measurements for Dark-eyed juncos in the Selkirk MountainsA
combination of morphological and body condition data collected in the
field, as well as LAB colour space data measured in Adobe Photoshop for
head and dorsal regions. Column heading abbreviations: FWS is the unique
individual identifier; std.l, std.a, and std.b are the L*A*B* colour
variables for a black standard colour chip included in each photo; head.l,
head.a, head.b are the L*A*B* colour variables for the mantle; back.l,
back.a, back.b are the L*A*B* colour variables for the dorsal
region.colour data_JAV-01050_R1.csvFeather microstructure measurements for
Dark-eyed junco in the Selkirk MountainsA combination of body condition
data and feather microstructure variables. Originally, all microstructure
variables were measured twice on two separate feathers. After finding
there was no difference between variables measured on separate feathers
(P>0.33), we pooled the variables within individual and the
averaged values are depicted in this data set (i.e., one row per
individual). Column heading abbreviations: penn.length &
plum.length are the linear measurements of the pennaceous and plumulaceous
feather regions respectively; penn.barb is the number of pennacous barbs
counted to measure density; penn.density.length is the length over which
the barbs were counted; penn.density is penn.barb/penn.density.length;
penn.barbules: this series is the same as the penn.barb columns but for
barbule densities measured twice (on two separate barbs); barbule.length:
measurements of individual barbule length from 5 randomly selected
barbules on the section of the barb that barbule density was
measured.feather microstructure data _ JAV-01050_R1.csvPlumage reflectance
data for Dark-eyed junco in the Selkirk MountainsA combination of body
condition data collected in the field and plumage reflectance data derived
from the R package 'pavo' (Maia et al. 2013) which is based on
Stoddard and Prum (2008)'s 'Tetracolourspace'. The data was
generated using an average avian visual and achromatic cone system. Column
heading abbreviations: u.p, s.p, m.p, l.p: proportion of ultra-violet,
short wave, medium wave, and long wave reflectance, respectively; u.r,
s.r, m.r, l.r: relative reflectance for each wavelength category; the
remaining variables (x, y, z, h.theta, h.phi, r.vec, r.max, and
r.achieved) were ultimately not used in the final analysis but serve to
place individuals in a 3D Tetracolourspace and also allow calculation of
variables such as brilliance and chroma which tend to be more important
for carotenoid colours (see Stoddard and Prum 2008 for a more detailed
description).Reflectance_JAV-01050_R1.csv
Revelstoke
British Columbia