Electronic supplemental material (ESM)
Evaluating the importance of trophobiosis in a Mediterranean ant community: a stable
isotope analysis
Katrin Brewitt1, Josep Piñol2, 3, Christiane Werner1,4, Wolfram Beyschlag1, Xavier Espadaler2, 3, Nicolás Pérez Hidalgo5,
Christian Platner1
1
Department of Experimental and Systems Ecology, University of Bielefeld, 33615 Bielefeld, Germany
2
CREAF, 08193 Cerdanyola del Vallès, Spain
3
Univ Autònoma Barcelona, Campus Bellaterra, 08193 Cerdanyola del Vallès, Spain
4
AgroEcoSystem Research, University of Bayreuth, 95447 Bayreuth, Germany
5
Department of Biodiversity and Environmental Management, University of León, 24071 León, Spain
e-mail: christian.platner@web.de
Table S1
Table S2
Table S3
Figure S1
Table S1 Number of observed contacts between aphids (sc=scale insect), their host plants and ants in June 2010: The number of ant species interacting with a single aphid species
(total with ant), the number of aphid contacts per ants species, the number of different host plants for a single aphid species, the number of different aphid species per host plant
species and the total number of aphid colonies found on a single host plant species (total with aphids) are given.
Aphididae (n=21)
sc
3
3
5
1
1
1
2
2
4
1
1
3
1
2
1
1
1
5
1
4
1
1
2
2
2
3
4
8
17
7
3
5
5
3
1
1
1
39
40
41
42
43
44
45
46
47
3
1
1
6
6
7
2
5
3
4
2
3
5
1
4
1
1
2
2
2
4
1
17
5
24
(1)
3
15
3
8
2
8
1
3
4
8
2
6
3
17
1
2
1
2
3
5
1
4
2
4
1
3
3
5
3
7
1
2
(2)
2
0
1
1
1
1
1
1
Number of different
host plants per aphid
species
38
Hirschfeldia incana
37
Rumex sp.
36
3
Hordeum murinum
35
2
2
Olea europaea
34
1
Punica granatum
33
Prunus persica
32
Asteraceae
9
6
Plantago sp.
31
1
1
Corylus avellana
30
Prunus dulcis
2
2
13
9
6
6
5
5
4
1
2
2
1
4
0
0
0
0
0
0
0
0
0
Carduus pycnocephalus
2
1
1
6
7
Avena barbata
1
Chaerophyllum sp.
29
Urtica urens
28
Pyrus communis
27
Malva parviflora
Formica rufibarbis
26
Citrus clementina
Camponotus aethiops
25
10
6
Sonchus tenerrimus
Pyramica membranifera
24
2
1
Total with ant
Plagiolepis pygmaea
23
No ant
Pheidole pallidula
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
Formica subrufa
Aphis spiraecola
Aphis gossypii
Baizongia pistaciae
Geoica urtricularia
Dysaphis plantaginea
Aphis sp.
Aphis umbrella
Brachycaudus amygdalinus
Aphididae Gen. sp. 1
Brachycaudus cardui
Sitobion avenae
Brachycaudus persicae
Brevicoryne brassicae
Myzus persicae
Corylobium avellanae
Hyalopterus amygdali
Myzocallis coryli
Uroleucon sp.
Uroleucon sonchi
Aphis fabae
Hyperomyzus lactucae
Ceroplastes sp.
Number of different contacts
Total with aphids
Host plants (n=18)
Lasius grandis
Formicidae (n=7)
7
5
1
1
1
2
1
1
1
1
2
1
1
1
1
1
1
2
1
5
1
Evaluating the importance of trophobiosis in a Mediterranean ant community: a stable isotope analysis
Katrin Brewitt, Josep Piñol, Christiane Werner, Wolfram Beyschlag, Xavier Espadaler, Nicolás Pérez Hidalgo, Christian
Platner (2015)
Insectes Sociaux
Table S2 Metrics of a tripartite network analysis of a trophobiotic mutualist network
Number of
combinations
(links)
1.Level
(Host-plantHemiptera)
2. Level
(Hemiptera-ants)
Mean links Connectance Nestedness Weighted
per species
temperature nestedness
(NODF)
H′2
Robustness
(higher level
species)
Generality
40
1
0.101
17.5
2.057
0.72
0.655
2.231
25
1.3
0.286
19.8
9.596
0.53
0.627
4.244
Connectance ranges from 0 to 1 and equals the proportion of realized interactions in the network.
Nestedness measures departure from systematic arrangement of species by niche width and ranges from 0 for fully nested (“cold”) to 100 for
non-nested, chaotic (“hot”) networks. The weighted index of nestedness WNODF expresses better how the nested pattern resembles
abundance gradients among species and ranges from 0 for non-nested to 100 for fully nested networks (Almeida-Neto M., Ulrich W. 2011. A
straightforward computational approach for measuring nestedness using quantitative matrices. Environ. Modell. Software 26:173–178).
The network-level measure of specialization H′2 ranges from 0 to 1 and quantifies the standardized two-dimensional entropy across the
matrix (Blüthgen et al. 2006).
Robustness R ranges from 0 to 1 and quantifies the secondary extinction risks of aphids following random extinctions of plant species and
accordingly the robustness of ant species against random extinctions of aphid species.
Generality is the effective mean number of host plant species per aphid species and of the visited aphid species per ant species, respectively.
Table S3 Mean shifts in stable isotope 13C und 15N contents between host-plant and aphid, with standard error of
the mean (S.E.), sorted by Δδ13C, number of analyzed samples in parentheses.
difference aphid host
13
plant δ C
13
S.E. δ C
difference aphid host
15
plant δ N
15
S.E. δ N
Corylobium avellanae (1)
-3,54
2,45
Ceroplastes sp (2)
-1,12
0,68
3,50
0,81
Aphis umbrella (4)
-0,92
1,12
3,83
1,04
Baizongia pistaciae (2)
-0,71
0,19
2,59
1,59
Brachycaudus amygdalinus (2)
-0,56
0,57
-1,53
1,32
Brachycaudus persicae (1)
-0,51
Aphis spiraecola (8)
-0,48
0,38
0,41
1,22
Hyperomyzus lactucae (16)
-0,43
0,24
-3,78
0,81
Aphis sp (3)
-0,37
0,57
-3,69
2,01
Aphis fabae (2)
-0,28
0,96
0,49
0,10
Sitobion avenae (5)
0,22
0,02
1,57
0,75
Uroleucon sonchi (5)
0,28
0,32
0,50
0,86
Brachycaudus cardui (2)
0,45
0,14
4,28
4,16
Hyalopterus amygdali (1)
0,49
Dysaphis plantaginea (3)
0,55
0,79
3,31
1,10
Aphis gosypii (11)
1,03
0,47
-2,38
0,66
Brevicoryne brassicae (1)
1,28
-6,97
Myzus persicae (1)
1,84
0,25
2,03
-3,59
3
Evaluating the importance of trophobiosis in a Mediterranean ant community: a stable isotope analysis
Katrin Brewitt, Josep Piñol, Christiane Werner, Wolfram Beyschlag, Xavier Espadaler, Nicolás Pérez Hidalgo, Christian
Platner (2015)
Insectes Sociaux
Pheidole pallidula (10)
Pyramica membranifera (1)
Camponotus aethiops (1)
Formica rufibarbis (1)
Plagiolepis pygmaea (2)
Lasius grandis (14)
Formica subrufa (12)
-6
-4
-2
0
2
difference 15N ant-aphid
4
6
8
10
difference 13C ant-aphid
Fig. S1 Mean difference in δ13C- and δ15N-values between ants and attended aphid colonies, with standard error
of the mean (error bars), sorted by Δδ13C, number of analyzed samples in parentheses (n differs from those in
Table S1, because more contacts were observed than samples were analyzed).
4