Resource Availability and Competition Shape the Evolution of Survival and Growth Ability in a Bacterial Community

Abstract

Resource availability is one of the main factors determining the ecological dynamics of populations or species. Fluctuations in resource availability can increase or decrease the intensity of resource competition. Resource availability and competition can also cause evolutionary changes in life-history traits. We studied how community structure and resource fluctuations affect the evolution of fitness related traits using a two-species bacterial model system. Replicated populations of Serratia marcescens (copiotroph) and Novosophingobium capsulatum (oligotroph) were reared alone or together in environments with intergenerational, pulsed resource renewal. The comparison of ancestral and evolved bacterial clones with 1 or 13 weeks history in pulsed resource environment revealed species-specific changes in life-history traits. Co-evolution with S. marcescens caused N. capsulatum clones to grow faster. The evolved S. marcescens clones had higher survival and slower growth rate then their ancestor. The survival increased in all treatments after one week, and thereafter continued to increase only in the S. marcescens monocultures that experienced large resource pulses. Though adaptive radiation is often reported in evolution studies with bacteria, clonal variation increased only in N. capsulatum growth rate. Our results suggest that S. marcescens adapted to the resource renewal cycle whereas N. capsulatum was more affected by the interspecific competition. Our results exemplify species-specific evolutionary response to both competition and environmental variation.

Geometrical Information Flow Regulated by Time Lengths: An Initial Approach

“…However, the results points for a perfect prediction for small periods of time, it confirms time as a factor that disrupts predictability regarding behavior of variables rather than potential information entropy [16]. When considering this thesis as a confirmation of the fact that thermodynamics concept given by Shannon [32] assumes, for these results of forecasting, the small effect in which each binary based interaction event tend to give several unpredictable outcomes due to diversity of pathways, but, nonetheless, those features are time regulated [3,4,9,11,13,16,19,22,28,30,31,[33][34][35][36][37][38], and phenomena of this kind are promoted by the flow of sequences among one unit to another one, composing the whole system as far as it has enough time to express its potential phase spaces.…”

The Potential of High‐throughput Metagenomic Sequencing of Aquatic Bacterial Communities to Estimate the Postmortem Submersion Interval

“…Lower temperature and higher oxygen conditions during the winter trial may have selected for specific bacteria in the environment to initially colonize the carcasses, which were then replaced by bacteria that originally resided in the carcass (e.g., internal gut communities). It is well‐known abiotic variables such as temperature, oxygen, and resource availability influence aquatic biofilm formation on nonliving surfaces (i.e., epilithic) in a way that affects community assembly . We suspect that this was the case in this study, shifting the bacterial taxa involved in the successional changes between winter and summer decomposition.…”

Feedback between environment and traits under selection in a seasonal environment: consequences for experimental evolution

“…Several experimental evolution studies have also shown that season lengths drive traits selection in batch culture. This has been found for instance in a study by Pekonnen et al [43] where bacteria (Serratia marcescens and Novosophingobium capsalatum) evolving in long batches of 7 days were mainly selected for a lower mortality rates rather than higher growth rates. On the contrary, in many other works [3][4][5][6][7][8]10,20,44,45] using one-day-long batches, the growth rate increased while the mortality rate remained unchanged.…”