Linking environmental quality and trait diversity in primary producers
Aquatic microbial primary producers exist in genetically variable populations, but are often studied as single lineages. However, the properties of lineages grown alone often fail to predict the composition of microbial assemblages. Different lineages of closely-related phytoplankton have unique growth strategies, and that they modulate their lineage growth rate in the presence of conspecifics. This explains why growth rates of lineages in isolation do not reliably predict the lineage composition of phytoplankton assemblages, even for simple monospecific populations. Since lineage growth is only one of many traits determining fitness in natural assemblages, we propose that in all but the poorest quality environments where allocating maximum energy to growth is the only viable strategy, we should expect intraspecific variation in growth strategies, with more strategies possible in ameliorated environments, such as high CO2 for many marine picoplankton. This emphasizes the importance of understanding and accounting for basic organismal biology in our models of aquatic primary producers, and makes a link between changes to environmental quality and differences in the expected variation in growth strategies of populations of primary producers.
Host: Justyna Wolinska