Endosymbiosis and its implications for evolutionary theory.
Ontology highlight
ABSTRACT:
SUBMITTER: O'Malley MA
PROVIDER: S-EPMC4547300 | biostudies-other | 2015 Aug
REPOSITORIES: biostudies-other
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Project description:The impressive body of work on the major evolutionary transitions in the last 20 y calls for a reconstruction of the theory although a 2D account (evolution of informational systems and transitions in individuality) remains. Significant advances include the concept of fraternal and egalitarian transitions (lower-level units like and unlike, respectively). Multilevel selection, first without, then with, the collectives in focus is an important explanatory mechanism. Transitions are decomposed into phases of origin, maintenance, and transformation (i.e., further evolution) of the higher level units, which helps reduce the number of transitions in the revised list by two so that it is less top-heavy. After the transition, units show strong cooperation and very limited realized conflict. The origins of cells, the emergence of the genetic code and translation, the evolution of the eukaryotic cell, multicellularity, and the origin of human groups with language are reconsidered in some detail in the light of new data and considerations. Arguments are given why sex is not in the revised list as a separate transition. Some of the transitions can be recursive (e.g., plastids, multicellularity) or limited (transitions that share the usual features of major transitions without a massive phylogenetic impact, such as the micro- and macronuclei in ciliates). During transitions, new units of reproduction emerge, and establishment of such units requires high fidelity of reproduction (as opposed to mere replication).
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Project description:How difficult is it to 'discover' an evolutionary adaptation or innovation? I here suggest that information theory, in combination with high-throughput DNA sequencing, can help answer this question by quantifying a new phenotype's information content. I apply this framework to compute the phenotypic information associated with novel gene regulation and with the ability to use novel carbon sources. The framework can also help quantify how DNA duplications affect evolvability, estimate the complexity of phenotypes and clarify the meaning of 'progress' in Darwinian evolution.This article is part of the themed issue 'Process and pattern in innovations from cells to societies'.
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Project description:BackgroundAlthough evolutionary theory is foundational and integrative in modern biology, there remains widespread lack of acceptance among U.S. residents. An interdisciplinary approach to teaching evolutionary theory at the undergraduate level has many advantages, such as giving students a context for learning about evolution and application of evolutionary theory to other academic disciplines and everyday life. While there are foundational examples of interdisciplinary approaches to teaching evolutionary theory, there are few examples of courses with application of evolutionary theory to issues of sustainability, such as conservation or global climate change. We build on the practical and theoretical work of others to create an interdisciplinary course on evolutionary theory for non-science majors, with ties to sustainability. Our course is taught in three modules, with extensive readings and hands-on lab activities. The first module is focused on honey bee biology, with hands-on beekeeping experiences; the second module on native plants and community education on sustainability; and the third module on the evolution of the subjective human experience of free will.ResultsWe found that students in our course experienced an increased acceptance of evolutionary theory. We found that students also met the course leaning objectives, of basic knowledge of evolutionary theory and application of evolutionary theory to other disciplines, assessed through group and individual major assignments. We also found that students had an expanded perspective on interdisciplinary application of evolutionary theory, assessed through closed-ended survey questions and analysis of open-ended writing.ConclusionsStudents in our course experienced an increase of acceptance of evolutionary theory and an expanded perspective on interdisciplinary application of evolutionary theory, despite the fact that many students were not science majors.Supplementary informationThe online version contains supplementary material available at 10.1186/s12052-023-00188-4.
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