10.5061/DRYAD.905QFTTGM
Shankar, Anusha
0000-0002-3043-6126
University of Alaska Fairbanks
Powers, Donald R
George Fox University
Dávalos, Liliana M
Stony Brook University
Graham, Catherine H
Swiss Federal Institute for Forest, Snow and Landscape Research
The allometry of daily energy expenditure in hummingbirds: an energy
budget approach
Dryad
dataset
2020
field metabolic rate
metabolic level boundaries hypothesis
tropics
avian allometry
energy budget
National Aeronautics and Space Administration
https://ror.org/027ka1x80
NNX11AO28G
Tinker Foundation
https://ror.org/01sv5w039
National Science Foundation
https://ror.org/021nxhr62
DEB-1442142
National Science Foundation
https://ror.org/021nxhr62
DEB-1838273
National Geographic Society
https://ror.org/04bqh5m06
9506-14
Stony Brook University Department of Ecology & Evolution
European Research Council
https://ror.org/0472cxd90
ADG number 787638
George Fox University
GFU2014G02
Swiss Federal Research Institute (WSL)
2020-01-13T00:00:00Z
2020-01-13T00:00:00Z
en
32588 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
1. Within-clade allometric relationships represent standard laws of
scaling between energy and size, and their outliers provide new avenues
for physiological and ecological research. According to the metabolic
level boundaries hypothesis, metabolic rates as a function of mass are
expected to scale closer to 0.67 when driven by surface-related processes
(e.g., heat or water flux), while volume-related processes (e.g.,
activity) generate slopes closer to one. 2. In birds, daily energy
expenditure (DEE) scales with body mass (M) in the relationship
log(DEE)=2.35+0.68log(M), consistent with surface-level processes
driving the relationship. However, taxon-specific patterns differ from the
scaling slope of all birds. 3. Hummingbirds have the highest mass-specific
metabolic rates among all vertebrates. Previous studies on a few
hummingbird species, without accounting for the phylogeny, estimated that
the DEE-body mass relationship for hummingbirds was log(DEE) =
1.72+1.21log(M). Contrary to theoretical expectations, this slope greater
than 1 indicates that larger hummingbirds are less metabolically efficient
than smaller hummingbirds. 4. We collected DEE and mass data for 12
hummingbird species, which, combined with published data, represented 17
hummingbird species in eight of nine hummingbird clades over a six-fold
size range of body size (2.7 - 17.5 g). 5. After accounting for
phylogenetic relatedness, we found daily energy expenditure scales with
body mass as log(DEE) = 2.04+0.95log(M). This slope of 0.95 is lower
than previously estimated for hummingbirds, but much higher than the slope
for all birds (0.68). The high slopes of torpor, hovering and flight
potentially explain the high interspecific DEE slope for hummingbirds
compared to other endotherms. 08-Jan-2020
Doubly labeled water data compiled from this study and the literature
(Powers & Nagy 1988, Weathers & Stiles 1991, Powers
& Conley 1994, Fernandez et al. 2011).
See Metadata file.