Dataset Information

Maintenance of Intraspecific Diversity in Response to Species Competition and Nutrient Fluctuations.

ABSTRACT: Intraspecific diversity is a substantial part of biodiversity, yet little is known about its maintenance. Understanding mechanisms of intraspecific diversity shifts provides realistic detail about how phytoplankton communities evolve to new environmental conditions, a process especially important in times of climate change. Here, we aimed to identify factors that maintain genotype diversity and link the observed diversity change to measured phytoplankton morpho-functional traits V_max and cell size of the species and genotypes. In an experimental setup, the two phytoplankton species Emiliania huxleyi and Chaetoceros affinis, each consisting of nine genotypes, were cultivated separately and together under different fluctuation and nutrient regimes. Their genotype composition was assessed after 49 and 91 days, and Shannon's diversity index was calculated on the genotype level. We found that a higher intraspecific diversity can be maintained in the presence of a competitor, provided it has a substantial proportion to total biovolume. Both fluctuation and nutrient regime showed species-specific effects and especially structured genotype sorting of C. affinis. While we could relate species sorting with the measured traits, genotype diversity shifts could only be partly explained. The observed context dependency of genotype maintenance suggests that the evolutionary potential could be better understood, if studied in more natural settings including fluctuations and competition.

SUBMITTER: Hamer J

PROVIDER: S-EPMC8779635 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:UnlabelledAnimal development and physiology depend on beneficial interactions with microbial symbionts. In many cases, the microbial symbionts are horizontally transmitted among hosts, thereby making the acquisition of these microbes from the environment an important event within the life history of each host. The light organ symbiosis established between the Hawaiian squid Euprymna scolopes and the bioluminescent bacterium Vibrio fischeri is a model system for examining how hosts acquire horizontally transmitted microbial symbionts. Recent studies have revealed that the light organ of wild-caught E. scolopes squid contains polyclonal populations of V. fischeri bacteria; however, the function and development of such strain diversity in the symbiosis are unknown. Here, we report our phenotypic and phylogenetic characterizations of FQ-A001, which is a V. fischeri strain isolated directly from the light organ of an E. scolopes individual. Relative to the type strain ES114, FQ-A001 exhibits similar growth in rich medium but displays increased bioluminescence and decreased motility in soft agar. FQ-A001 outcompetes ES114 in colonizing the crypt spaces of the light organs. Remarkably, we find that animals cocolonized with FQ-A001 and ES114 harbor singly colonized crypts, in contrast to the cocolonized crypts observed from competition experiments involving single genotypes. The results with our two-strain system suggest that strain diversity within the squid light organ is a consequence of diversity in the single-strain colonization of individual crypt spaces.ImportanceThe developmental programs and overall physiologies of most animals depend on diverse microbial symbionts that are acquired from the environment. However, the basic principles underlying how microbes colonize their hosts remain poorly understood. Here, we report our findings of bacterial strain competition within the coevolved animal-microbe symbiosis composed of the Hawaiian squid and bioluminescent bacterium Vibrio fischeri Using fluorescent proteins to differentially label two distinct V. fischeri strains, we find that the strains are unable to coexist in the same niche within the host. Our results suggest that strain competition for distinct colonization sites dictates the strain diversity associated with the host. Our study provides a platform for studying how strain diversity develops within a host.

Project description:Interspecific competition from introduced and naturally colonizing species has potential to affect resident populations, but demographic consequences for vertebrates have rarely been tested. We tested hypotheses of interspecific and intraspecific competition for density, body mass, and fertility of adult female Roe Deer (Capreolus capreolus) across a heterogeneous forest landscape occupied by two introduced deer species: Mediterranean Fallow Deer (Dama dama); and subtropical Reeve's Muntjac (Muntiacus reevesi). Species-specific deer densities in buffers around culling locations of 492 adult female Roe Deer, sampled over seven years, were extracted from spatially explicit models calibrated through annual nocturnal distance sampling. Roe Deer fertility and body mass were related to species-specific deer densities and extent of arable lands using piecewise structural equation models. Reeve's Muntjac density was lower at higher Fallow Deer densities, suggesting interspecific avoidance via interference competition, but greater when buffers included more arable land. Roe Deer body mass was marginally greater when buffers included more arable land and was independent of deer densities. However, Roe Deer fertility was unrelated to female body mass, suggesting that fertility benefits exceeded an asymptotic threshold of body condition in this low-density population. However, Roe Deer fertility was slightly greater rather than reduced in areas with greater local Roe Deer density, suggesting negligible intraspecific competition. In contrast, Roe Deer was less fertile in areas with greater Reeve's Muntjac densities; thus, interspecific exceeded intraspecific competition in this assemblage. In contrast, we found no support for any effects of Fallow Deer density on Roe Deer density, body mass, or fertility. Complex networks of interspecific competition operating in this deer assemblage include: interspecific interference from Fallow Deer exceeded habitat effects for Reeve's Muntjac; and interspecific competition from introduced, smaller sedentary Reeve's Muntjac reduced fertility, unlike intraspecific, or potential competition with larger, more mobile, Fallow Deer for native Roe Deer. Mechanisms driving Roe Deer fertility may include interspecific behavioral interference or stress-resource depletion is considered less likely because Roe Deer fertility was independent of body mass. Findings emphasize the importance of ensuring appropriate management strategies for controlling invasive species.

Dataset Information

Maintenance of Intraspecific Diversity in Response to Species Competition and Nutrient Fluctuations.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets