Functional Ecology
SUPPLEMENTARY FIGURE CAPTIONS
Figure S1. Observed and predicted relationship between body size (snout vent length, SVL) and
wet mass. The observed relationship comes from Fig. 2 in Tinkle and Ballinger (1972), mass =
3.793*10-5SVL2.983, R2 = 0.99. This implies a shape correction factor, δM, of 0.2474 (Table 1b).
Figure S2. Predicted and observed (Tinkle & Dunham 1986) relationship between body size
(measured as snout-vent length, SVL) at maturity vs. mean maximum body size. The predicted
relationship sometimes exceeds the observed value, potentially because at some sites individuals
do not survive long enough to reach maximum size.
Figure S3. Example hourly output for the middle day of each month from the coupled
biophysical/Dynamic Energy Budget models.
Figure S4. Fits of observed (points) vs. predicted (lines) development time (a), assimilation rate
(b) and resting metabolic rate (c) based on a common Arrhenius relationship (see Table S1 for
parameters). Dotted lines show uncorrected Arrhenius responses (akin to Q10 responses) while
solid lines show the Sharp adjustment (see Kooijman 2010 p. 21). Observed data are from
(Hughes et al. 1982; Andrews et al. 2000; Angilletta 2001a, b).
Figure S5. Predicted and observed resting oxygen consumption and assimilation rates. Part a)
shows oxygen consumption rate plotted against wet body mass for a body temperature of 30 °C.
The data points come from the literature for S. undulatus (Angilletta 2001a, b) and the related S.
Metabolic theory, life history, and the distribution of a terrestrial ectotherm
Michael Kearney
Functional Ecology
occidentalis (Dawson & Bartholomew 1956). The solid black line shows the DEB prediction and
the light grey line shows the empirically estimated interspecific allometric curve for lizards
(Andrews & Pough 1985). The thick black line shows a power function fitted to the DEB curve,
which has a mass exponent of 0.82. The DEB prediction comes directly from the stoichiometric
elements of the theory, assuming uric acid as the nitrogenous waste and that the molecular
composition of food, structure, reserve and products have, for every carbon atom, 1.8 hydrogen
atoms, 0.5 oxygen atoms and 0.15 nitrogen atoms (see section 4.31 of Kooijman 2010). Part b)
shows the predicted vs. ‘observed’ assimilation rate, the latter coming either from Angilletta
(2001a) (closed circles) or the polynomial function fitted by Waldschmidt and reported in Grant
and Porter (1992) (open circles). The fine dotted line shows the 1:1 relationship.
Figure S6. a) Predicted (lines) and observed (symbols) growth trajectories for laboratory-raised
Sceloporus undulatus from either Utah (grey line, triangles) or Oklahoma (dark line, squares).
Dynamic Energy Budget model predictions are based on zoom factors (z) of 1 (Utah) and 0.92
(Oklahoma). b) Predicted and observed relationships between snout vent length (SVL) and body
mass for the same two populations (Utah, grey; Oklahoma, black; observed relationship, solid
line; predicted relationship, dotted lines). Data are from Ferguson and Talent (1993).
Figure S7. Observed (dots) and predicted (lines) maximum and minimum available operative
temperatures for Sceloporus merriami (slightly smaller than S. undulatus) at Big Bend National
Park in Texas. Observed data come from (Grant & Dunham 1988) and are based on means from
12 or more measurements from painted copper models during late June and mid July during clear
Metabolic theory, life history, and the distribution of a terrestrial ectotherm
Michael Kearney
Functional Ecology
days. Predictions are from the biophysical model (Niche Mapper) based on the global dataset of
long-term climatic averages for the point nearest to the study site, for clear skies in mid July.
Figure S8. Predicted trajectories of wet body mass, reserve density and 12pm body temperatures
for integrated biophysical/Dynamic Energy Budget simulations of Sceloporus undulatus at the
11 sites for which detailed life history data exists (see Table S1 for abbreviations of place
names). Sites are in order of lowest to highest potential activity time. Predictions are based either
on the Utah body size and clutch size (left column) or the locally observed body and clutch sizes
(right column). Reserve density (J/cm3) has been divided by 100. Sudden drops in wet mass
represent oviposition events, periods of low body temperature represent inactive times of the
year due to cold (at which times the reserve density drops below the maximum level).
Figure S9. Spatially explicit predictions of a) annual activity hours, b) lifetime clutches, and c)
probability of survival to the end of year 3. All predictions are based on the estimated parameters
for the Utah population. The solid black line represents the approximate rage limit within the
USA while the filled triangles represent the sites for which detailed life history data are
available, summarized in Tinkle and Dunham (1986).
Figure S10. Predicted fraction of egg development for Sceloporus undulatus between June and
September at two different depths in the soil, based on the following Arrhenius relationship
derived from Parker and Andrews (2007): Tcor (temperature correction factor) = 1/(1+
EXP(TAL*(1/(273+Tsoil)-1/TL))+EXP(TAH(1/TH-1/(273+Tsoil)))); development per hour =
k1*EXP(TA /T1-TA /(Tsoil +273))*Tcor*(1/24). Parameters were: TA = 9600, TAL = 50000, TAH =
Metabolic theory, life history, and the distribution of a terrestrial ectotherm
Michael Kearney
Functional Ecology
90000, TL = 290, TH = 307.5, k1 = 0.0139, T1 = 298. Grey areas show where development would
not complete.
Figure S11. Predicted degree days of development for Sceloporus undulatus between June and
September at two different depths in the soil, based on data from Parker and Andrews (2007).
The lower critical temperature for degree day calculation was 17 °C. Parker and Andrews
predicted the minimum heat sum for development to be approximately 495 degree days (grey
colours therefore show where development would not complete.).
Metabolic theory, life history, and the distribution of a terrestrial ectotherm
Michael Kearney
Functional Ecology
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Functional Ecology
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Metabolic theory, life history, and the distribution of a terrestrial ectotherm
Michael Kearney