Supporting Information
The following Supporting Information is available for this article online.
Table S1. Indices used in the analysis. μ = mean; Var = variance; pij = proportion of jth prey genus in individual i’s diet ; qj = proportion of jth prey genus in
the whole generation’s prey spectrum; ej = proportion of jth prey genus in the orthopteran community sampled in the environment; xij = weight of the jth prey
item in individual i’s diet.
Niche width
Description
Population
Individual
with:
Niche width of prey taxa.
D
Di
D
1
1
; Di 
2
qj
 pij2
j
Niche width of prey taxa in relation to environmental
PS
-
j
PS  1  0.5 q j  e j
j
abundance.
Niche width of prey size: variance in the size of the
whole generation’s prey (or orthopterans in the
environment).
TNW
WIC
TNW  WIC  BIC  Var ( xij )


BIC  Var  x i 
WIC   Var xij i 
ij
WIC: Within-individual component of variance.
BIC: Between-individual component of variance.
1
Individual
Proportional similarity between individuals and
specialization
population diet (taxa).
Proportional within-individual component of total
niche width (size).
IS
PSi
IS  PSi ; PSi  1  0.5 pij  q j
j
R's I
-
R ' sI 
WIC
TNW
2
Table S2. Number of individuals of orthopterans collected (and identified at least at the generic level) from the environment (E) and among wasp prey (P)
during the activity of the two generations (first generation: I; second generation: II), and statistical differences between frequencies (only if sample size
adequate). In brackets the collected species for each genus are shown.
Family
Acrididae
Acrididae
Pyrgomorphidae
Acrididae
Acrididae
Acrididae
Genus (Species)
Calliptamus (C. barbarus)
Acrotylus (A. insubricus)
Pyrgomorpha (P. conica)
Tropidopola (T. cylindrica)
Sphingonotus (S. arenarius)
Anacridium (A. aegyptium)
n E (I) n P (I)
68
131
30
7
29
1
206
3
12
9
1
22
n E (II) n P (II) E vs. P (I) E vs. P (II)
152
96
54
37
32
4
60
8
40
60
0
14
I vs. II (E)
I vs. II (P)
(df=1)
(df=1)
(df=1)
(df=1)
χ2=290.5,
χ2=2.8,
χ2=8.3,
χ2=42.5,
P<0.0001
P=0.10
P=0.08
P<0.0001
χ2=123.2,
χ2=32.9,
χ2=28.2,
χ2=4.2,
P<0.0001
P<0,0001
P<0.0001
P=0.383
χ2=10.8,
χ2=6.7,
χ2=0.8,
χ2=25.5,
P<0.001
P<0.01
P=0.942
P<0.0001
χ2=0.4,
χ2=95.8,
χ2=11.0,
χ2=56.4,
P=0.53
P<0.0001
P=0.03
P<0.0001
χ2=27.4,
χ2=16.6,
χ2=1.3,
-
P<0.0001
P<0.0001
P=0.864
χ2=430.7,
χ2=68.6,
-
χ2=0.2,
3
Acrididae
Acrididae
Heteracris (H. littoralis)
Pezotettix (P. giornae)
0
0
0
12
17
0
9
2
P<0.0001
P<0.0001
-
χ2=0.0,
-
P=0.997
P= χ2=11.5,
0.75
P=0.02
-
-
χ2=4.5,
P=0.34
Acrididae
Acrida
3
0
4
0
-
-
Gryllidae
Gryllomorpha
1
0
3
0
-
-
-
-
Gryllidae
Oecanthus (O. pellucens)
1
1
0
0
-
-
-
-
Tettigoniidae
Thyreonotus
1
0
0
0
-
-
-
-
Conocephalidae
Ruspolia (R. nitidula)
0
0
1
0
-
-
-
-
Phaneropteridae
Tylopsis (T. liliifolia)
0
0
1
0
-
-
-
-
Acrididae
Brachycrotaphus (B. tryxalicerus)
0
0
0
1
-
-
-
-
Phaneropteridae
Phaneroptera (P. falcata)
0
0
0
1
-
-
-
-
272
266
401
195
Total
-
4
Table S3. Number of individuals of grasshoppers of the 7 most hunted genera collected in the two different habitats considered, and statistical differences
between frequencies (only if sample size adequate).
Genus
generation I
χ2 (df=1)
generation II
Soil/Grass
Bushes
Soil/Grass
Bushes
generation I
generation II
Acrotylus
115
16
86
10
χ2= 21.51, P<0.0001
χ2= 68.38, P<0.0001
Calliptamus
23
45
40
112
χ2= 39.50, P<0.0001
χ2= 27.20, P<0.0001
Pyrgomorpha
19
11
16
38
χ2= 0.46,P=0.5
χ2= 6.87, P<0.01
Sphingonotus
26
3
30
2
χ2= 5.76, P<0.025
χ2= 27.52, P<0.0001
Tropidopola
-
7
4
33
-
χ2= 19.91, P<0.0001
Heteracris
-
-
-
9
-
-
Anacridium
-
1
-
4
-
-
183
83
176
199
Total
5
Table S4. Mean weight±SD (mg) of orthopterans collected from the environment (E) and among wasp prey (P), and the theoretical maximum lift (Max lift) of
wasps which hunted for each genus, during the activity of the two generations (first generation: I; second generation: II). Sum of sample sizes for wasps do
not match the total number of wasps because most wasps hunted for more than one genus so that they were included in more samples. Only grasshoppers of
the 7 most hunted genera were considered (sample sizes in Table S2), but the data on community (last row) refers to the whole sample (see totals in Table
S2).
Genus
E (I)
P (I)
E (II)
P (II)
Max lift (I) (n)
Max lift (II) (n)
Calliptamus
79 ± 43
63 ± 26
233 ± 189
166 ± 64
0.176 ± 0.02 (31)
0.184 ± 0.02 (21)
Acrotylus
48 ±31
60 ± 16
79 ± 36
104 ± 55
0.18 ± 0.02 (2)
0.175 ± 0.02 (6)
Pyrgomorpha
68 ± 46
62 ± 23
75 ± 50
79 ± 43
0.176 ± 0.02 (7)
0.176 ± 0.02 (19)
Tropidopola
104 ± 74
261 ± 143
163 ± 100
217 ± 76
0.175 ± 0.03 (4)
0.189 ± 0.02 (21)
Sphingonotus
131 ± 59
106
204 ± 93
-
0.166
-
Anacridium
260
113 ± 46
350 ± 465
100 ± 42
0.171 ± 0.03 (3)
0.169 ± 0.03 (7)
Heteracris
-
-
441 ± 244
210 ± 16
-
0.192 ± 0.02 (7)
Community
67 ± 50
74 ± 52
175 ± 172
156 ± 81
178 ± 25 (42)
185 ± 24 (46)
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Table S5. Number of individuals of the three most abundant orthopteran genera per size class collected from the environment (E) and among wasp prey (P)
during the activity of the two generations (first generation: I; second generation: II), and statistical differences between frequencies. Size classes with too little
sample for both generations, which did not allow the statistical analysis, were not reported.
Genus
Size class
n E (I) n P (I)
n E (II) n P (II) E vs. P (I) (df=1)
E vs. P (II)
(df=1)
Calliptamus
Pyrgomorpha
Tropidopola
Class 1 (1-50 mg)
19
80
2
0
χ2=8.5, P<0.01
-
Class 2 (51-100 mg)
28
111
23
8
χ2=7.9, P<0.01
χ2=9.8, P<0.01
Class 3 (101-200 mg)
15
15
64
39
χ2=20.9, P<0.001
χ2=8.7, P<0.01
Class 4 (>200 mg)
1
0
58
14
-
χ2=32.5, P<0.001
Class 1 (1-50 mg)
13
20
4
16
χ2=9.9, P<0.01
χ2=34.7, P<0.001
Class 2 (51-100 mg)
7
18
8
16
χ2=0.6, P>0.05
χ2=7.7, P<0.05
Class 3 (101-200 mg)
7
16
0
12
χ2=1.5, P>0.05
-
Class 4 (>200 mg)
0
0
0
0
-
-
Class 1 (1-50 mg)
0
0
0
0
-
-
Class 2 (51-100 mg)
5
6
2
1
χ2=6.1, P<0.05
-
7
Class 3 (101-200 mg)
1
16
1
22
χ2=51.5, P<0.001
χ2=434.4, P<0.001
Class 4 (>200 mg)
1
11
6
35
χ2=18.5, P<0.001
χ2=41.2, P<0.001
8
Figure S1. Pictures showing the very different body shapes of two abundantly grasshopper genera. a) Tropidopola, b) Calliptamus (lateral and dorsal view).
9