Online resource 4

Species traits

Data and methods described here refer to the trait data collected for all the species in the seed dispersal network from a grassland-forest mosaic (30°25’S; 52°21’W) that illustrates our analytical framework.

We used five plant traits in our analyses, two continuous (dispersule diameter and maximum plant height), and three categorical traits (aril presence, diaspore shape and color). We collected 10 dispersules from each species in order to estimate their average diameter (mm). For the species we were not able to collect at least 10 dispersules in the study site, we complemented our sample using specimens from the ICN UFRGS Herbarium. Measurements were taken using a caliper to the nearest 0.1 mm. Data on maximum plant height (m) were acquired from the literature (Lorenzi 2008). Color and shape were treated as dummy variables (five for colors and three for shape [spherical, ellipsoidal and triangular]). Data on dispersule shape and color were also attained from the literature (Lorenzi 2008) and based on our own field observations. For further details on measuring plant traits see Cornelissen et al. (2003) and Pérez-Harguindeguy et al. (2013).

For birds we measured four continuous traits of animals captured in the study site: body length (cm), beak length (cm), beak height (cm) and the hand-wing index (HW), defined as:

HW = 100 xWL-SLWL eqn 1

where, WL is the length of the closed wing and SL is the distance from the carpal joint to the tip of the first secondary feather (Claramunt et al. 2011). It has been empirically demonstrated that the HW, a wing shape index, is a good surrogate of flight ability (Claramunt et al. 2011). Measurements were taken using a caliper to the nearest 0.1 mm, and for each species we measure from 1 to 34 individuals in order to estimate their average trait value. We also measured the ratio between wing breadth and length and collected some complementary data on the other aforementioned traits from specimens of bird collections of the Science and Technology Museum - PUCRS (Museu de Ciência e Teconologia da PUCRS) and the Museum of Natural Sciences of the Rio Grande do Sul Zoobotanical Foundation (Fundação Zoobotânica do Rio Grande do Sul). The number of each species that we measured varied according to their availability in bird collections (from 1 to 10 specimens). For further details on measuring avian morphological traits see Winker (1998).

‬‬References‬‬‬‬‬‬

Claramunt, S. et al. (2011). High dispersal ability inhibits speciation in a continental radiation of passerine birds. Proceedings of the Royal Society B-Biological Sciences,279, 1567-1574.

Cornelissen, J.H.C. et al. (2003). A handbook of protocols for standardised and easy measurement of plant functional traits worldwide. Australian Journal of Botany, 51, 335-380.

Lorenzi, H. (2008) Árvores brasileiras: manual de identificação e cultivo de plantas arbóreas nativas do Brasil, 5 edn. Instituto Plantarum.

Pérez-Harguindeguy, N. et al. (2013). New handbook for standardised measurement of plant functional traits worldwide. Australian Journal of Botany, 61, 167-234.

Winker, K. (1998). Suggestions for measuring external characters of birds. - Ornitología Neotropical, 9, 23-30.