1
|
Tarkington J, Zufall RA. Correlated responses to selection across diverse environments during experimental evolution of Tetrahymena thermophila. Ecol Evol 2024; 14:e11395. [PMID: 39045496 PMCID: PMC11264346 DOI: 10.1002/ece3.11395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 04/19/2024] [Accepted: 04/26/2024] [Indexed: 07/25/2024] Open
Abstract
Correlated responses to selection have long been observed and studied; however, it remains unclear when they will arise, and in what direction. To contribute to a growing understanding of correlated responses to selection, we used experimental evolution of the ciliate Tetrahymena thermophila to study direct and correlated responses in a variety of different environmental conditions. One experiment focused on adaptation to two different temperatures and the correlated responses across temperatures. Another experiment used inhibitory concentrations of a variety of compounds to test direct and correlated responses to selection. We found that all populations adapted to the environments in which they evolved. We also found many cases of correlated evolution across environments; few conditions resulted in trade-offs and many resulted in a positive correlated response. Surprisingly, in many instances, the correlated response was of a larger magnitude than the direct response. We find that ancestral fitness predicts the extent of adaptation, consistent with diminishing returns epistasis. Unexpectedly, we also find that this pattern of diminishing returns holds across environments regardless of the environment in which evolution occurs. We also found that the correlated response is asymmetric across environments, that is, the fitness of a population evolved in one environment and assayed in a second was inversely related to the fitness of a population evolved in the second environment and assayed in the first. These results support the notion that positive correlated responses to selection across environments are frequent, and worth further study.
Collapse
Affiliation(s)
- Jason Tarkington
- Department of Biology and BiochemistryUniversity of HoustonHoustonTexasUSA
- Department of GeneticsStanford UniversityStanfordCaliforniaUSA
| | - Rebecca A. Zufall
- Department of Biology and BiochemistryUniversity of HoustonHoustonTexasUSA
| |
Collapse
|
2
|
Heightened immune surveillance in Drosophila melanogaster populations selected for faster development and extended longevity. Heliyon 2022; 8:e12090. [PMID: 36544838 PMCID: PMC9761728 DOI: 10.1016/j.heliyon.2022.e12090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 10/11/2022] [Accepted: 11/25/2022] [Indexed: 12/12/2022] Open
Abstract
Maximization of life-history traits is under constraints due to both, limitations of resource acquisition and the restricted pathways of resource allocation. Drosophila melanogaster has served as an excellent model organism to not only unravel various trade-offs among life history traits but also numerous aspects of host immune response. Drosophila larvae are semi-aquatic that live, feed and excrete inside the food source-often over-ripe fruits and vegetables that are rich in both commensal and pathogenic microbiota that can impact the larval survival. In this study, we have used six populations of D. melanogaster, three of which are selected for faster pre-adult development and extended adult longevity, and their three ancestral controls, to explore the impact of selection on the basal immune activity in the larval stage. The larvae from selected populations had nearly significantly upregulated plasmatocyte density, significantly higher percent phagocytosis, phagocytic index and higher transcript levels of Tep3, eater and NimC1. Selected populations also had significantly upregulated crystal cell number along with higher transcript of PPO2. Out of seven tested AMPs level, Drosomycin was significantly upregulated in selected populations while Drosocin was significantly higher in control populations. ROS levels were comparable in the selected and control populations. Our results strongly suggest that enhanced basal immune activity during larval stage manages the faster development and could be responsible for comparable larval survival of selected and control populations.
Collapse
|
3
|
Visher E, Uricchio L, Bartlett L, DeNamur N, Yarcan A, Alhassani D, Boots M. The evolution of host specialization in an insect pathogen. Evolution 2022; 76:2375-2388. [PMID: 35946063 DOI: 10.1111/evo.14594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Revised: 05/21/2022] [Accepted: 06/06/2022] [Indexed: 01/22/2023]
Abstract
Niche breadth coevolution between biotic partners underpins theories of diversity and co-existence and influences patterns of disease emergence and transmission in host-parasite systems. Despite these broad implications, we still do not fully understand how the breadth of parasites' infectivity evolves, the nature of any associated costs, or the genetic basis of specialization. Here, we serially passage a granulosis virus on multiple inbred populations of its Plodia interpunctella host to explore the dynamics and outcomes of specialization. In particular, we collect time series of phenotypic and genetic data to explore the dynamics of host genotype specialization throughout the course of experimental evolution and examine two fitness components. We find that the Plodia interpunctella granulosis virus consistently evolves and increases in overall specialization, but that our two fitness components evolve independently such that lines can specialize in productivity or infectivity. Furthermore, we find that specialization in our experiment is a highly polygenic trait best explained by a combination of evolutionary mechanisms. These results are important for understanding the evolution of specialization in host-parasite interactions and its broader implications for co-existence, diversification, and infectious disease management.
Collapse
Affiliation(s)
- Elisa Visher
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA
| | | | - Lewis Bartlett
- Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, 30602, USA
| | | | - Aren Yarcan
- University of California, Berkeley, CA, 94720, USA
| | | | - Mike Boots
- Department of Integrative Biology, University of California, Berkeley, CA, 94720, USA.,Centre for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter Penryn Campus, Penryn, TR10 9FE, UK
| |
Collapse
|
4
|
Performance Trade-Offs in Elite Swimmers. ADAPTIVE HUMAN BEHAVIOR AND PHYSIOLOGY 2021. [DOI: 10.1007/s40750-021-00179-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|