Figure 1.
Path analyses for local and regional diversity of flowerhead feeders of Asteraceae. (A) several subfamilies, especially, Asteroideae and Mutisioideae, in Brazil; modified from Lewinsohn (1991LEWINSOHN, T.M. 1991. Insects in flower heads of Asteraceae in southeast Brazil: a tropical case study on species richness. In Plant-Animal Interactions: Evolutionary Ecology in Tropical and Temperate Regions (P.W. Price, T.M. Lewinsohn, G.W. Fernandes & W.W. Benson, eds.) Wiley/Interscience, New York, p. 525–560., Figure 23.6). Flowerhead size: dry weight. Host taxon size: number of species in host tribe. Host area: ordinal variable, three classes. Alpha diversity: insect richness, standardized by rarefaction on twenty host individuals. Positive paths blue, continuous arrows; negative paths red, stippled. Only main path coefficients are shown. Analysis for 44 plant species. (B) Carduoideae in Europe, modified from Zwölfer (1987ZWÖLFER, H. 1987. Species richness, species packing, and evolution in insect-plant systems. Ecol. Stud. 61:301–319. Springer, Berlin., Figure 4, grey arrows from Figure 3). Flowerhead size: diameter. Host taxon size: log number of species in host genus. Host area: number of countries in Europe where the host species is found. Alpha diversity: insect richness in 100 flowerheads. Two other causal variables, habitat and host life type, had no significant effects and were excluded for simplicity; thin arrows are non-significant. Analysis for 37 plant species.
Figure 2.
Regions and main localities sampled for Asteraceae and flowerhead-feeding insects in South and Southeast Brazil, between 1994 and 2002. Representative assemblages and interactions (recorded through rearing immatures from flowerhead samples) are shown as binary bipartite networks with plant species on the bottom and herbivores on top. County abbreviations: BJa (Bom Jardim da Serra, Santa Catarina); Mogi (Mogi Mirim, São Paulo); CJo (Campos do Jordão, São Paulo); SCa (Serra do Cabral, Minas Gerais).
Figure 3.
Bipartite networks for the tribe Eupatorieae (Asteraceae) and their flowerhead-feeding insects in two localities in the Mantiqueira mountain range: (A) Itatiaia, (B) Campos do Jordão (see
Figure 2). Rectangles on top are insect species, ellipses on the bottom are host species. The widths of the rectangles and ellipses represent the relative abundance in each level; basal widths of the wedges represent the relative frequency of each pairwise interaction. In insects, colors represent three feeding guilds (strict endophages with complete development within one flowerhead, green – Diptera, red – Lepidoptera; blue – facultative endophages). Different colours of plants represent subtribes of Eupatorieae. See
Almeida (2001)ALMEIDA, A.M. 2001. Biogeografia de interações entre Eupatorieae (Asteraceae) e insetos endófagos de capítulos na Serra da Mantiqueira. PhD Thesis, Universidade Estadual de Campinas, Campinas. Available at https://repositorio.unicamp.br/Busca/Download?codigoArquivo=484206
https://repositorio.unicamp.br/Busca/Dow...
for details.
Figure 4.
A schematic representation of herbivore specialization, incorporating relatedness and availability of host plants. In this framework, herbivores are classified into three categories: specialists feed on plants that are more closely related than expected if herbivores used plants according to their abundance; generalists are the opposite, feeding on plants that are distantly related; non-selective herbivores use host plants proportionately to their availability. (A) Herbivores feed on plants with different levels of relatedness. (B) Herbivore diets can be proportional to availability, or deviate from it, selecting either similar resources (specialists) or dissimilar resources (generalists). (C) Host specialization of species in the four most important herbivore families in our previously described dataset, assessed with the metric DSI* (Jorge et al. 2014JORGE, L.R., PRADO, P.I., ALMEIDA-NETO, M. & LEWINSOHN, T.M. 2014. An integrated framework to improve the concept of resource specialisation. Ecol. Lett. 17:1341–1350., 2017JORGE, L.R., NOVOTNY, V., SEGAR, S.T., WEIBLEN, G.D., MILLER, S.E., BASSET, Y. & LEWINSOHN, T.M. 2017. Phylogenetic trophic specialization: a robust comparison of herbivorous guilds. Oecologia 185: 551–559.). Species are colored according to the specialization categories in (B). Adapted from Jorge et al. (2014)JORGE, L.R., PRADO, P.I., ALMEIDA-NETO, M. & LEWINSOHN, T.M. 2014. An integrated framework to improve the concept of resource specialisation. Ecol. Lett. 17:1341–1350..
Figure 5.
An interaction network of Asteraceae (tribe Vernonieae; 81 species) and insects (Diptera, Tephritidae; 35 species) in the Espinhaço Range, Minas Gerais. Insect-plant links (total = 163, connectance = 0.058) are depicted in two ways. (A) An adjacency matrix with plants in rows, insects in columns. Rows and columns are arranged first by detecting modules (shown in different colors) and then sorting species in each module for nestedness (details in Pinheiro et al. 2019PINHEIRO, R.B.P., FELIX, G.M.F., DORMANN, C.F. & MELLO, M.A.R. 2019. A new model explaining the origin of different topologies in interaction networks. Ecology 100:1–30.). (B) a bipartite network with plants on the left, insects on the right. Modules are identified by the same colors. Data from Prado & Lewinsohn (2004)PRADO, P.I. & LEWINSOHN, T.M. 2004. Compartments in insect–plant associations and their consequences for community structure. J. Anim. Ecol. 73:1168–1178., original figure by Rafael Pinheiro.
Figure 6.
A frugivory network in the Intervales State Park within the Atlantic Forest. Green circles are plant species (184); orange squares are bird species (81). Symbol size is proportional to number of links. The most connected species are highlighted in yellow, respectively Myrsine coriacea(Primulaceae, 59 links), and Chiroxiphia caudata (Pipridae, 35 links). Data from Silva et al. (2002)SILVA, W.R., DE MARCO, P., HASUI, E., & GOMES, V.S.M. 2002. Patterns of fruit-frugivores interactions in two Atlantic Forest bird communities of South-eastern Brazil: implications for conservation. In: Seed dispersal and frugivory: ecology, evolution and conservation (eds. Levey, D.J, Silva, W.R, and Galetti, M.). CAB International, Wallingford, p.423-435., original figure by Carine Emer.
Figure 7.
Collector’s curves for species and interactions in cerrado localities in the state of São Paulo (main localities shown in Figure 2). Five of eight localities were resampled in different seasons, totalling 23 samples (details in Almeida et al. 2005ALMEIDA, A.M., FONSECA, C.R., PRADO, P.I., ALMEIDA-NETO, M., DINIZ, S., KUBOTA, U., BRAUN, M.R., RAIMUNDO, R.L.G., ANJOS, L.A.D., MENDONÇA, T.G., FUTADA, S.M., & LEWINSOHN, T.M. 2005. Diversidade e ocorrência de Asteraceae em cerrados de São Paulo. Biota Neotrop. 5:27–43.). Continuous curves show the total number of plants, insects and interactions found as species accumulate. The dashed line shows the connectance, the proportion of potential links actually recorded in each cumulative sample set. Original figure.
Figure 8.
Number of unique interactions between Asteraceous host species and endophagous flowerhead herbivores in 20 cerrado remnants encompassing a gradient of invasion by exotic grasses. The disturbance metric is the mean invasive grass cover (in 45 plots of 30m × 5m per remnant), with the following ordinal scale: (1) 0%; (2) 1 – 25%, (3) 26% – 50%, (4) 51% – 75%, (5) 75% – 100%. Redrawn from Almeida-Neto et al. (2011)ALMEIDA-NETO, M., PRADO, P.I. & LEWINSOHN, T.M. 2011. Phytophagous insect fauna tracks host plant responses to exotic grass invasion. Oecologia 165:1051–1062..