Data file is created with Microsoft Excel 2010. Data are acquired experimentally. The different sheets represent
independent datasets on juvenile characteristics of the study species Chiasmia clathrata (Geometridae, Lepidoptera).
Although there may be duplicate family or individual identity codes in separate sheets, each row represents a
separate family [Sheet 1 (Clinal variation) & Sheet 2 (Experiment_a, except for families within populations Somero,
Halikko, Tornio and Pello) or individual [Sheet 3 (Experiment_b) & Sheet 4 (Experiment_c)]. Larvae were invariably
fed ad libitum on the natural host plant Lathyrus pratensis (column headings: Host plant).
Sheet 1 (Clinal variation):
Data are acquired experimentally by rearing offspring of wild-caught females (column heading: Family) sampled
from 18 locations (column heading: Population; exact locations given under column headings “Longitude” and
“Latitude”). For each sampling site, we derived estimates of thermal environment as monthly temperature for each
summer month [column headings: Average Temperature (August)(ºC), Average Temperature (July)(ºC), Average
Temperature (June)(ºC)] averaged over observed daily temperatures in the years 2001–2008 (data provided by
Finnish and Estonian Meteorological Institutes). Sampling sites were classified by habitat type with respect to
humidity (column heading: Habitat type). Meadows with rich herbaceous vegetation (agricultural wastelands,
pastures and shoreline meadows) were considered mesic, whereas dry meadows on sandy soil with sparse
vegetation (road banks, urban wastelands) were considered xerothermic. Larvae were reared singly in 0.25 l plastic
containers [Column heading: Larval density (1/0.25l)] in a large climate room at 20ºC [Column heading: Rearing
temperature (°C)] under continuous light (Philips TLD 36 W/840, 3350 lm) [Column heading: Day length (h)]. The
column headings “Frequency (greens)” and “Frequency (browns)” stand for the frequencies of non-melanic and
melanic larvae within each family. Five days after pupation, the pupae were weighed to the nearest 0.01 mg with a
precision balance (Mettler Toledo MT5). Pupal weighs were averaged within families [column heading: Familyspecific average pupal mass (mg)].
Sheet 2 (Experiment_a):
Data are acquired experimentally by rearing F1 offspring of randomly selected wild-caught females (column heading:
Family) captured from four locations (column heading: Population; exact locations given under column headings
“Longitude” and “Latitude”). Two populations originated from a strictly univoltine region and another two from a
southern region where at least a partial summer generation emerges regularly (column heading: Region). Larvae
were reared in climate rooms either at 14ºC or 20ºC [column heading: Rearing temperature (ºC)] under continuous
light (Philips TLD 36 W/840, 3350 lm) [column heading: Day length (h)] in groups of five in 0.2 l plastic containers
[column heading: Larval density (1/0.2 l)] so that each family was divided between the two temperatures (five larvae
/ family / temperature). The column headings “Frequency (greens)” and “Frequency (browns)” stand for the
frequencies of non-melanic and melanic larvae within a particular family-temperature combination. Five days after
pupation, the pupae were weighed to the nearest 0.01 mg with a precision balance (Mettler Toledo MT5). Pupal
weighs were averaged within families [column heading: Family-specific average pupal mass (mg)].
Sheet 3 (Experiment_b):
Data are acquired experimentally by rearing larvae singly in 0.2 l plastic containers under two light regimes [column
heading: Day length (h)] and the levels of incident radiation (column heading: Level of incident radiation) in climate
chambers [1.0 m × 0.75 m (depth) × 1.4 m (height); Weiss Technik Bio 1000] at 20ºC [column heading: Rearing
temperature (ºC)]. The level of incident radiation was manipulated so that some containers were directly exposed to
radiation emitted by 17 fluorescent lamps [0.5 m apart from the lamps (Osram L 30W/830)] at the chamber ceiling,
whereas the other set of containers was placed on a shelf below (1.05 m apart from the lamps). The larvae were
offspring of randomly selected F3 generation females (column heading: Family) that derived from four laboratory
stocks representing four populations (column heading: Population; exact original locations given under column
headings “Longitude” and “Latitude”), which originated either from a strictly univoltine region or a region where at
least a partial summer generation emerges regularly (column heading: Region).
Laboratory stocks derived from wild-caught females (38–72 females / population). Randomly selected neonate
larvae (ca. 300 / population) formed the founder populations. Populations were maintained separately in identical
conditions [7h, 21ºC (light) : 17h, 18ºC (dark)]. Larvae were housed in 10 l buckets and fed on L. pratensis in groups
of ca. 300 individuals until the ultimate instar, and then transferred into larger buckets (50 l) and reared until
pupation. Pupae overwintered in a refrigerator (4ºC) for nine months between the consecutive generations. Adults
were allowed to reproduce in containers (25 l) with equal sex ratios (max 200 individuals / container) and L.
pratensis for egg-laying. The population sizes were > 600 individuals in each generation.
The individually reared larvae were monitored daily to assess the phenotype they express (column heading:
Phenotype).The duration of larval period [column heading: Larval development time (days)] was determined as days
since the egg hatched until the larva ceased feeding and started to pupate. Five days later, the pupa was weighed to
the nearest 0.01 mg with a precision balance (Mettler Toledo MT 5) to determine its acquired mass [column heading:
Pupal mass (mg)] and sexed based on the sex-specific genital scars on the pupal cuticle (column heading: Sex). An
index of larval growth rate (c) was derived from the growth model by Tammaru and Esperk (2007):
c
m pupa
1 /(1b )
t larva
,
(1)
where mpupa is pupal mass, tlarva is larval development time and b is an allometric exponent relating anabolism to
body mass. We calculated growth rate estimates for b values of 0.75, 0.8 and 0.85. Absolute growth rates were
standardized by subtracting the sample mean and dividing by the standard deviation of the whole sample. The
respective standardized growth rates are given under column headings “Standardized larval growth rate (b=0.75)”,
“Standardized larval growth rate (b=0.80)” and “Standardized larval growth rate (b=0.85)”.
Sheet 4 (Experiment_c):
Data are acquired experimentally by rearing larvae singly in 0.2 l plastic containers in a full-factorial split-brood
design under two levels of incident radiation [column heading: Level of incident radiation] and temperatures
[column heading: Rearing temperature (ºC)] in climate chambers [1.0 m × 0.75 m (depth) × 1.4 m (height); Weiss
Technik Bio 1000] with a constant light condition [column heading: Day length (h)]. The level of incident radiation
was manipulated so that some containers were directly exposed to radiation emitted by 17 fluorescent lamps [0.5 m
apart from the lamps (Osram L 30W/830)] at the chamber ceiling, whereas the other set of containers was placed on
a shelf below (1.05 m apart from the lamps). The larvae were offspring of randomly selected F3 generation females
(column heading: Family) that derived from eight laboratory stocks representing artificial selection lines for either
green or brown larval phenotype (column heading: Artificial selection line) (parental phenotypes either green ×
green or brown × brown). The eight artificial selection lines derived from four populations (column heading:
Population; exact original locations given under column headings “Longitude” and “Latitude”), which originated
either from a strictly univoltine region or a region where at least a partial summer generation emerges regularly
(column heading: Region).
Artificial selection lines derived from wild-caught females (38–72 females / population). Randomly selected neonate
larvae (ca. 1000 / population) formed the founder populations, which were divided into three groups to establish
three laboratory lines for each of the four populations. Larvae were reared in 10 l buckets on L. pratensis in groups
of ca. 300 individuals until the ultimate instar. In one of the three lines, we selected for the brown larval colour, in
another one the green larval colour, while the third stock served as a control in which no selection was performed.
Artificial selection was performed in the course of five generations so that target phenotypes (i.e. green or brown
dependent on the line) were transferred into larger buckets (50 l) and reared until pupation. The “wrong”
phenotypes were discarded. Populations and the three population-specific stocks were reared separately in identical
conditions [7h, 21ºC (light) : 17h, 18ºC (dark)]. Pupae overwintered in a refrigerator (4ºC) for nine months between
the consecutive generations. Adults were allowed to reproduce in containers (25 l) with equal sex ratios (max 200
individuals / container) and L. pratensis for egg-laying. The population sizes were > 600 individuals in each
generation.
The individually reared larvae were monitored daily to assess the phenotype they express (column heading:
Phenotype).The duration of larval period [column heading: Larval development time (days)] was determined as days
since the egg hatched until the larva ceased feeding and started to pupate. Five days later, the pupa was weighed to
the nearest 0.01 mg with a precision balance (Mettler Toledo MT 5) to determine its acquired mass [column heading:
Pupal mass (mg)] and sexed based on the sex-specific genital scars on the pupal cuticle (column heading: Sex). An
index of larval growth rate (c) was derived from the growth model by Tammaru and Esperk (2007):
c
m pupa
1 /(1b )
t larva
,
(1)
where mpupa is pupal mass, tlarva is larval development time and b is an allometric exponent relating anabolism to
body mass. We calculated growth rate estimates for b values of 0.75, 0.8 and 0.85. Absolute growth rates were
standardized by subtracting the sample mean and dividing by the standard deviation of the whole sample. The
respective standardized growth rate values are given under column headings “Standardized larval growth rate
(b=0.75)”, “Standardized larval growth rate (b=0.80)” and “Standardized larval growth rate (b=0.85)”.
Tammaru, T. & Esperk, T. 2007. Growth allometry in immature insects: larvae do not grow exponentially. Functional
Ecology 21: 1099–1105.