Unraveling the relative contribution of inter‐ and intrapopulation functional variability in wild populations of a tadpole species

Abstract

Functional traits are increasingly recognized as an integrative approach by ecologists to quantify a key facet of biodiversity. And these traits are primarily expressed as species means in previous studies, based on the assumption that the effects of intraspecific variability can be overridden by interspecific variability when studying functional ecology at the community level. However, given that intraspecific variability could also have important effects on community dynamics and ecosystem functioning, empirical studies are needed to investigate the importance of intraspecific variability in functional traits. In this study, 256 Scutiger boulengeri tadpole individuals from four different populations are used to quantify the functional difference between populations within a species, and the relative contribution of inter‐ and intrapopulation variability in functional traits. Our results demonstrate that these four populations differ significantly in functional attributes (i.e., functional position, functional richness, and low functional overlap), indicating that individuals from different populations within a species should be explicitly accounted for in functional studies. We also find similar relative contribution of inter‐ (~56%) and intrapopulation (~44%) variation to the total variability between individuals, providing evidence that individuals within populations should also be incorporated in functional studies. Overall, our results support the recent claims that intraspecific variability cannot be ignored, as well as the general idea of “individual level” research in functional ecology.

Intraspecific and interspecific trait variability in tadpole meta‐communities from the Brazilian Atlantic rainforest

“…Tadpoles from a single species can adapt to the availability of microhabitats or to local conditions (e.g., canopy cover, predation pressure, density‐dependence, Strauβ et al, ), which means ITV could be locally high for traits related to their position in the water column (body shape) or to the use of different resource types (Eterovick & Fernandes, ; Kopp & Eterovick, ). However, this contrasts with the findings of Zhao et al (), who found traits to be also widely variable among populations for a given species.…”

“…This variability was not simply driven by ontogeny, because all the stages presented similar variability in the different traits (Supporting information Figure S2). This is in agreement with the literature on tadpoles, which suggests that morphological characters are highly variable within species because anuran larvae are highly adaptive to their environment (Grosjean, 2005 Baldo et al, 2014), and even single species (Zhao et al, 2017). Interestingly, our results are overall in agreement with decompositions of trait variation performed in plants, as most studies have found between 25% and 33% of trait variation to occur within species (Albert et al, 2010;Messier et al, 2010;Siefert et al, 2015).…”

“…Here, the tail compression index (TCI) presented high levels (69%) of intraspecific variability in both datasets (Atlantic forest and Amazonia). Several studies have also shown that wide morphological variations can be found within a single genus ( Melanophryiniscus , Baldo et al, ), and even single species (Zhao et al, ). Interestingly, our results are overall in agreement with decompositions of trait variation performed in plants, as most studies have found between 25% and 33% of trait variation to occur within species (Albert et al, ; Messier et al, ; Siefert et al, ).…”

“…Secondly, tadpoles represent the major part of the biomass in freshwater habitats (Altig, Whiles, & Taylor, 2007), being important primary and secondary consumers, and therefore are known to play a major role in ecosystem functioning (Strauβ, Reeve, Randrianiaina, Vences, & Glos, 2010). However, we still know little regarding the assembly of natural communities of amphibians at larval stage (Grözinger, Thein, Feldhaar, & Rödel, 2014;Strauβ et al, 2010;Zhao, Li, Wang, Xie, & Jiang, 2017).…”

Turnover or Intraspecific Trait Variation: Explaining Functional Variability in a Neotropical Anuran Metacommunity

“…It has been demonstrated that ITV for several groups of organisms across different environmental gradients is high -e.g. trees, Jung et al (2010), Fajardo and Siefert (2018); invertebrates, Rudolf and Rasmussen (2013) , Dahirel et al (2017); and tadpoles, Zhao et al (2017), Jordani et al (2019) -strongly contributing to the increase of alpha and beta diversities (e.g. Spasojevic et al, 2016).…”