Body size variation in aquatic consumers causes pervasive community effects, independent of mean body size

Abstract

Intraspecific phenotypic variation is a significant component of biodiversity. Body size, for example, is variable and critical for structuring communities. We need to understand how homogenous and variably sized populations differ in their ecological responses or effects if we are to have a robust understanding of communities. We manipulated body size variation in consumer (tadpole) populations in mesocosms (both with and without predators), keeping mean size and density of these consumers constant. Size‐variable consumer populations exhibited stronger antipredator responses (reduced activity), which had a cascading effect of increasing the biomass of the consumer's resources. Predators foraged less when consumers were variable in size, and this may have mediated the differential effects of predators on the community composition of alternative prey (zooplankton). All trophic levels responded to differences in consumer size variation, demonstrating that intrapopulation phenotypic variability can significantly alter interspecific ecological interactions. Furthermore, we identify a key mechanism (size thresholds for predation risk) that may mediate impacts of size variation in natural communities. Together, our results suggest that phenotypic variability plays a significant role in structuring ecological communities.

Gut McIrobiomeis Associated with Hepatopancreatic and Gonadal Transcriptomes and Together They Impact on Growth Traits in <em>M. rosenbergii</em>

“…rosenbergii, the third highest freshwater aquaculture production in China and in the world, is an important source of high-quality animal protein for human, and its global production increases 5% annually owing to its growth rate advantage (Hossain and Chakraborty, 2017). Consistent with the dimorphic characteristics of body size in most aquatic animals, there are also significant gender differences in the body size of adult M. rosenbergii (Carlson and Langkilde, 2017). In the same rearing environment, sexually mature male prawns are significantly larger than female prawns, and their weights can be 2 to 3 times of the female animal (Barki et al 1997), which is consistent with the results of this study.…”

Toxicity and genotoxicity of imidacloprid in the tadpoles of Leptodactylus luctator and Physalaemus cuvieri (Anura: Leptodactylidae)

“…Under stress, such as the presence of contaminants, efforts to tolerate the presence of pesticides may compromise an individual’s metabolism and growth 47 . Reduced development of the tadpoles may make them more vulnerable to predation in natural environments, because of both their smaller size (e.g., Carlson and Langkilde 48 ) and their reduced physical capacity. Although body size is a highly variable characteristic, there is a general correlation between the size of the tadpoles and the adults 49 .…”

Using a space‐for‐time substitution approach to predict the effects of climate change on nutrient cycling in tropical island stream ecosystems

“…In order to accurately forecast the effects of global change on ecosystem function, it is important to assess impacts of climate change across scales of ecological organization. For example, body size is an important trait for predicting the effects of biological change on ecosystem function (Fritschie and Olden 2016; Carlson and Langkilde 2017). However, studies have shown that population properties (e.g., density, size structure) also play an important role in altering ecosystem function (Jackson et al 2017; Frauendorf 2019).…”