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Articles 1 - 8 of 8
Full-Text Articles in Life Sciences
Convergent Evolution Of Conserved Mitochondrial Pathways Underlies Repeated Adaptation To Extreme Environments, Ryan Greenway, Nick Barts, Chathurika Henpita, Anthony P Brown, Lenin Arias Rodriguez, Carlos M Rodríguez Peña, Sabine Arndt, Gigi Y Lau, Michael P Murphy, Lei Wu, Dingbo Lin, Michael Tobler, Joanna L Kelley, Jennifer H. Shaw
Convergent Evolution Of Conserved Mitochondrial Pathways Underlies Repeated Adaptation To Extreme Environments, Ryan Greenway, Nick Barts, Chathurika Henpita, Anthony P Brown, Lenin Arias Rodriguez, Carlos M Rodríguez Peña, Sabine Arndt, Gigi Y Lau, Michael P Murphy, Lei Wu, Dingbo Lin, Michael Tobler, Joanna L Kelley, Jennifer H. Shaw
PCOM Scholarly Papers
Extreme environments test the limits of life; yet, some organisms thrive in harsh conditions. Extremophile lineages inspire questions about how organisms can tolerate physiochemical stressors and whether the repeated colonization of extreme environments is facilitated by predictable and repeatable evolutionary innovations. We identified the mechanistic basis underlying convergent evolution of tolerance to hydrogen sulfide (H2S)-a toxicant that impairs mitochondrial function-across evolutionarily independent lineages of a fish (Poecilia mexicana, Poeciliidae) from H2S-rich springs. Using comparative biochemical and physiological analyses, we found that mitochondrial function is maintained in the presence of H2S in sulfide …
Interspecific Gene Flow Potentiates Adaptive Evolution In A Hybrid Zone Formed Between Pinus Strobiformis And Pinus Flexilis, Mitra Menon
Theses and Dissertations
Species range margins are often characterised by high degrees of habitat fragmentation resulting in low genetic diversity and higher gene flow from populations at the core of the species range. Interspecific gene flow from a closely related species with abutting range margins can increase standing genetic diversity and generate novel allelic combinations thereby alleviating limits to adaptive evolution in range margin populations. Hybridization driven interspecific gene flow has played a key role in the demographic history of several conifer due to their life history characteristics such as weak crossability barriers and long generation times. Nevertheless, demonstrating whether introgression is adaptive …
Plant Evolutionary Response To Climate Change: Detecting Adaptation Across Experimental And Natural Precipitation Gradients, Jacqueline J. Peña
Plant Evolutionary Response To Climate Change: Detecting Adaptation Across Experimental And Natural Precipitation Gradients, Jacqueline J. Peña
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Global climate change is a real-time problem that presents threats to many species. Climate change can alter ecosystems and may lead to species extinction. Species can respond to climate change by moving to a better environment or adapting. Therefore, it is necessary to rely on several approaches and perspectives to anticipate ecological impacts of climate change. A common strategy uses models to understand how populations respond to different climate scenarios. Ecological models have helped us understand population persistence, but they often ignore how populations adapt to environmental stress. Adaptive evolution has been ignored because it was assumed that evolution was …
The Adaptive Evolution Of Herbivory In Freshwater Systems, Jessica Lynn Sanchez Montelongo
The Adaptive Evolution Of Herbivory In Freshwater Systems, Jessica Lynn Sanchez Montelongo
FIU Electronic Theses and Dissertations
Herbivory is thought to be nutritionally inefficient relative to carnivory and omnivory. But, herbivory evolved from carnivory in many lineages, suggesting that there are advantages to eating plants. To understand the adaptive significance of the transition from carnivory to herbivory, I proposed five hypotheses for the adaptive evolution of herbivory and reviewed the current freshwater literature to identify conditions where eating plants might be adaptive over eating animals. I tested three of these ideas (Suboptimal Habitat, Heterotroph Facilitation, and Lipid Allocation) using the herbivorous Sailfin Molly (Poecilia latipinna)and identified each as a potential mechanism for the evolution of …
Effect Of Temperature And Genetic Structure On Adaptive Evolution At A Dynamic Range Edge In The North American Gypsy Moth (Lymantria Dispar L.), Trevor M. Faske
Effect Of Temperature And Genetic Structure On Adaptive Evolution At A Dynamic Range Edge In The North American Gypsy Moth (Lymantria Dispar L.), Trevor M. Faske
Theses and Dissertations
The study of biological invasions is not only essential to regulate their vast potential for ecological and economical harm, they offer a unique opportunity to study adaptive evolution in the context of recent range expansions into novel environments. The North American invasion of the gypsy moth, Lymantria dispar L., since its introduction in 1869 to Massachusetts, has expanded westward to Minnesota, northward to Canada, and southward to North Carolina. Fluctuating range dynamics at the southern invasive edge are heavily influenced by heat exposure over their optimal (supraoptimal) during the larval stage of development. We coupled genomic sequencing with reciprocal …
Positive Selection Linked With Generation Of Novel Mammalian Dentition Patterns, Joao P. Machado, Siby Philip, Emanuel Maldonado, Stephen J. O'Brien, Warren E. Johnson
Positive Selection Linked With Generation Of Novel Mammalian Dentition Patterns, Joao P. Machado, Siby Philip, Emanuel Maldonado, Stephen J. O'Brien, Warren E. Johnson
Biology Faculty Articles
A diverse group of genes are involved in the tooth development of mammals. Several studies, focused mainly on mice and rats, have provided a detailed depiction of the processes coordinating tooth formation and shape. Here we surveyed 236 tooth-associated genes in 39 mammalian genomes and tested for signatures of selection to assess patterns of molecular adaptation in genes regulating mammalian dentition. Of the 236 genes, 31 (∼13.1%) showed strong signatures of positive selection that may be responsible for the phenotypic diversity observed in mammalian dentition. Mammalian-specific tooth-associated genes had accelerated mutation rates compared with older genes found across all vertebrates. …
A Preliminary Study Of The Role Of Nickel In Enhancing Flowering Of The Nickel Hyperaccumulating Plant Alyssum Inflatum Nyár. (Brassicaceae), R. Ghasemi, Z. Zare Chavoshi, R.S. Boyd, Nishanta Rajakaruna
A Preliminary Study Of The Role Of Nickel In Enhancing Flowering Of The Nickel Hyperaccumulating Plant Alyssum Inflatum Nyár. (Brassicaceae), R. Ghasemi, Z. Zare Chavoshi, R.S. Boyd, Nishanta Rajakaruna
Biological Sciences
Alyssum inflatum is a native of serpentine soils and is able to hyperaccumulate nickel (Ni), but the importance of Ni to reproduction in the species is unknown. We investigated if reproductive fitness is enhanced by Ni in the growth medium, and included a treatment involving a relatively high level of Mg to provide a comparison with elevated levels of another metal. Seedlings were grown in a modified Hoagland solution culture in an inert medium of Perlite and were treated with Ni (100 μM), a high concentration of Mg (5 mM), or under control conditions (solution culture without Ni or the …
Systematic Changes In Gene Expression Patterns Following Adaptive Evolution In Yeast, Tracy L. Ferea, David Botstein, Patrick O. Brown, R. Frank Rosenzweig
Systematic Changes In Gene Expression Patterns Following Adaptive Evolution In Yeast, Tracy L. Ferea, David Botstein, Patrick O. Brown, R. Frank Rosenzweig
Biological Sciences Faculty Publications
Culturing a population of Saccharomyces cerevisiae for many generations under conditions to which it is not optimally adapted selects for fitter genetic variants. This simple experimental design provides a tractable model of adaptive evolution under natural selection. Beginning with a clonal, founding population, independently evolved strains were obtained from three independent cultures after continuous aerobic growth in glucose-limited chemostats for more than 250 generations. DNA microarrays were used to compare genome-wide patterns of gene expression in the evolved strains and the parental strain. Several hundred genes were found to have significantly altered expression in the evolved strains. Many of these …