Evolutionary Impact Research Articles

Adaptations and metabolic evolution of myzozoan protists across diverse lifestyles and environments.

SUMMARYMyzozoans encompass apicomplexans and dinoflagellates that manifest diverse lifestyles in highly varied environments. They show enormous propensity to employ different metabolic programs and exploit different nutrient resources and niches, and yet, they share much core biology that underlies this evolutionary success and impact. This review discusses apicomplexan parasites of medical significance and the traits and properties they share with non-pathogenic myzozoans. These include the versatility of myzozoan plastids, which scale from fully photosynthetic organelles to the site of very select key metabolic pathways. Pivotal evolutionary innovations, such as the apical complex, have allowed myzozoans to shift from predatory to parasitic and other symbiotic lifestyles multiple times in both apicomplexan and dinoflagellate branches of the myzozoan evolutionary tree. Such traits, along with shared mechanisms for nutrient acquisition, appear to underpin the prosperity of myzozoans in their varied habitats. Understanding the mechanisms of these shared traits has the potential to spawn new strategic interventions against medically and veterinary relevant parasites within this grouping.

Spontaneous single-nucleotide substitutions and microsatellite mutations have distinct distributions of fitness effects.

The fitness effects of new mutations determine key properties of evolutionary processes. Beneficial mutations drive evolution, yet selection is also shaped by the frequency of small-effect deleterious mutations, whose combined effect can burden otherwise adaptive lineages and alter evolutionary trajectories and outcomes in clonally evolving organisms such as viruses, microbes, and tumors. The small effect sizes of these important mutations have made accurate measurements of their rates difficult. In microbes, assessing the effect of mutations on growth can be especially instructive, as this complex phenotype is closely linked to fitness in clonally evolving organisms. Here, we perform high-throughput time-lapse microscopy on cells from mutation-accumulation strains to precisely infer the distribution of mutational effects on growth rate in the budding yeast, Saccharomyces cerevisiae. We show that mutational effects on growth rate are overwhelmingly negative, highly skewed towards very small effect sizes, and frequent enough to suggest that deleterious hitchhikers may impose a significant burden on evolving lineages. By using lines that accumulated mutations in either wild-type or slippage repair-defective backgrounds, we further disentangle the effects of 2 common types of mutations, single-nucleotide substitutions and simple sequence repeat indels, and show that they have distinct effects on yeast growth rate. Although the average effect of a simple sequence repeat mutation is very small (approximately 0.3%), many do alter growth rate, implying that this class of frequent mutations has an important evolutionary impact.

Research on collaborative innovation behavior of enterprise innovation ecosystem under evolutionary game

Establishing an innovation ecosystem revitalizes enterprises by fostering collaboration with other entities within the system. This collaboration results in increased resources for innovation and development, further strengthening participants' innovation and survival capacities. As the existing literature on collaborative innovation behavior within innovation ecosystems is relatively limited, the primary objective of this study is to investigate the evolutionary process and impact factors of players' collaborative innovation behavior in the enterprise innovation ecosystem (EIE). This study establishes an evolutionary game (EG) model that includes three players in an EIE to analyze their collaborative innovation behaviors in scenarios where their initial strategic probabilities are low, medium, and high. The simulation results indicate the existence of six potential evolutionary stable strategies (ESSs) within the system. The ideal ESS identified in this three-party evolutionary game model is characterized by “active collaboration, active collaboration, participation”. Furthermore, the player's behaviors in different states are affected by initial probability, synergy sensitivity, transformation efficiency, output elasticity, subsidy, punishment, and public impact. The results of this study reveal the mechanism of collaborative innovation behavior among different players in the EIE, providing beneficial references for its sustainable development.

40th Anniversary Virtual Issues: Evolutionary Impacts of Endosymbiosis

40th Anniversary Virtual Issues: Evolutionary Impacts of Endosymbiosis

The Evolutionary Impact of Artificial Intelligence on Contemporary Artistic Practices

This article explores the transformative influence of Artificial Intelligence (AI) on contemporary art, focusing on the integration of AI in creative processes, the reception of AI-generated art, and the ethical considerations it raises. As AI technologies become more sophisticated, they redefine artistic creation, collaboration, and interaction, expanding the traditional boundaries of art. By employing AI, artists access new tools for enhancing creativity, automating production, and engaging audiences through interactive installations. However, this integration also brings challenges, particularly concerning the authenticity and ethical implications of AI-generated art. The article discusses AI's role in augmenting creativity, its impact on art production, the dynamic ways it engages audiences, and the ethical dilemmas it presents, such as data privacy and intellectual property rights. The discussion aims to provide a comprehensive understanding of how AI is reshaping the art world, influencing artistic communities, and prompting a reevaluation of art in the digital age.

Regulatory and evolutionary impact of DNA methylation in two songbird species and their naturally occurring F1 hybrids

BackgroundRegulation of transcription by DNA methylation in 5’-CpG-3’ context is a widespread mechanism allowing differential expression of genetically identical cells to persist throughout development. Consequently, differences in DNA methylation can reinforce variation in gene expression among cells, tissues, populations, and species. Despite a surge in studies on DNA methylation, we know little about the importance of DNA methylation in population differentiation and speciation. Here we investigate the regulatory and evolutionary impact of DNA methylation in five tissues of two Ficedula flycatcher species and their naturally occurring F1 hybrids.ResultsWe show that the density of CpG in the promoters of genes determines the strength of the association between DNA methylation and gene expression. The impact of DNA methylation on gene expression varies among tissues with the brain showing unique patterns. Differentially expressed genes between parental species are predicted by genetic and methylation differentiation in CpG-rich promoters. However, both these factors fail to predict hybrid misexpression suggesting that promoter mismethylation is not a main determinant of hybrid misexpression in Ficedula flycatchers. Using allele-specific methylation estimates in hybrids, we also determine the genome-wide contribution of cis- and trans effects in DNA methylation differentiation. These distinct mechanisms are roughly balanced in all tissues except the brain, where trans differences predominate.ConclusionsOverall, this study provides insight on the regulatory and evolutionary impact of DNA methylation in songbirds.

The radical impact of oxygen on prokaryotic evolution-enzyme inhibition first, uninhibited essential biosyntheses second, aerobic respiration third.

Molecular oxygen is a stable diradical. All O2-dependent enzymes employ a radical mechanism. Generated by cyanobacteria, O2 started accumulating on Earth 2.4 billion years ago. Its evolutionary impact is traditionally sought in respiration and energy yield. We mapped 365 O2-dependent enzymatic reactions of prokaryotes to phylogenies for the corresponding 792 protein families. The main physiological adaptations imparted by O2-dependent enzymes were not energy conservation, but novel organic substrate oxidations and O2-dependent, hence O2-tolerant, alternative pathways for O2-inhibited reactions. Oxygen-dependent enzymes evolved in ancestrally anaerobic pathways for essential cofactor biosynthesis including NAD+, pyridoxal, thiamine, ubiquinone, cobalamin, heme, and chlorophyll. These innovations allowed prokaryotes to synthesize essential cofactors in O2-containing environments, a prerequisite for the later emergence of aerobic respiratory chains.

Fusion/fission protein family identification in Archaea.

The majority of newly discovered archaeal lineages remain without a cultivated representative, but scarce experimental data from the cultivated organisms show that they harbor distinct functional repertoires. To unveil the ecological as well as evolutionary impact of Archaea from metagenomics, new computational methods need to be developed, followed by in-depth analysis. Among them is the genome-wide protein fusion screening performed here. Natural fusions and fissions of genes not only contribute to microbial evolution but also complicate the correct identification and functional annotation of sequences. The products of these processes can be defined as fusion (or composite) proteins, the ones consisting of two or more domains originally encoded by different genes and split proteins, and the ones originating from the separation of a gene in two (fission). Fusion identifications are required for proper phylogenetic reconstructions and metabolic pathway completeness assessments, while mappings between fused and unfused proteins can fill some of the existing gaps in metabolic models. In the archaeal genome-wide screening, more than 1,900 fusion/fission protein clusters were identified, belonging to both newly sequenced and well-studied lineages. These protein families are mainly associated with different types of metabolism, genetic, and cellular processes. Moreover, 162 of the identified fusion/fission protein families are archaeal specific, having no identified fused homolog within the bacterial domain. Our approach was validated by the identification of experimentally characterized fusion/fission cases. However, around 25% of the identified fusion/fission families lack functional annotations for both composite and split states, showing the need for experimental characterization in Archaea.IMPORTANCEGenome-wide fusion screening has never been performed in Archaea on a broad taxonomic scale. The overlay of multiple computational techniques allows the detection of a fine-grained set of predicted fusion/fission families, instead of rough estimations based on conserved domain annotations only. The exhaustive mapping of fused proteins to bacterial organisms allows us to capture fusion/fission families that are specific to archaeal biology, as well as to identify links between bacterial and archaeal lineages based on cooccurrence of taxonomically restricted proteins and their sequence features. Furthermore, the identification of poorly characterized lineage-specific fusion proteins opens up possibilities for future experimental and computational investigations. This approach enhances our understanding of Archaea in general and provides potential candidates for in-depth studies in the future.

History of Diversification and Adaptation from North to South Revealed by Genomic Data: Guanacos from the Desert to Sub-Antarctica.

The increased availability of quality genomic data has greatly improved the scope and resolution of our understanding of the recent evolutionary history of wild species adapted to extreme environments and their susceptibility to anthropogenic impacts. The guanaco (Lama guanicoe), the largest wild ungulate in South America, is a good example. The guanaco is well adapted to a wide range of habitats, including the Sechura Desert, the high Andes Mountains to the north, and the extreme temperatures and conditions of Navarino Island to the south. Guanacos also have a long history of overexploitation by humans. To assess the evolutionary impact of these challenging habitats on the genomic diversity, we analyzed 38 genomes (∼10 to 16×) throughout their extensive latitudinal distribution from the Sechura and Atacama Desert to southward into Tierra del Fuego Island. These included analyses of patterns of unique differentiation in the north and geographic region further south with admixture among L. g. cacsilensis and L. g. guanicoe. Our findings provide new insights on the divergence of the subspecies ∼800,000 yr BP and document two divergent demographic trajectories and to the initial expansion of guanaco into the more southern portions of the Atacama Desert. Patagonian guanacos have experienced contemporary reductions in effective population sizes, likely the consequence of anthropogenic impacts. The lowest levels of genetic diversity corresponded to their northern and western limits of distribution and some varying degrees of genetic differentiation. Adaptive genomic diversity was strongly linked with environmental variables and was linked with colonization toward the south followed by adaptation.

Norovirus infection in children in Romania

Norovirus represents the most frequent cause of pediatric gastroenteritis requiring medical care. We conducted a prospective study on 276 patients admitted to a tertiary hospital in Romania from January 2017 to December 2019 to estimate the clinic-epidemiological and evolutionary impact of Norovirus infection. Among the 276 patients, the median age was 2.34 years, and 57.61% were male. The frequency of hospitalizations in a year was higher in August, September, and October, and 72.1% of patients were from urban areas. Diarrhea (92.58%), vomiting (83.33%), anorexia (92.03%), and fever (57.61%) predominated, while abdominal pain (46.74%), nausea (30.8%), headache (18.84%), and myalgia (18.12%) were in lower percentages. Dehydration occurred in 99.28% of patients. Using the Pearson correlation coefficient, we formulated two hypotheses: in the 0-4 years category, the number of cases requiring hospitalization is inversely proportional to age (Pearson coefficient age-number of cases - 0.92), and the younger the age, the more it is associated with other infections and the longer the hospitalization duration. Conclusions. The clinic-epidemiological characteristics of patients with Norovirus infection are influenced by age – the younger the age, the longer the hospitalization duration and the higher the presence of associated infections; the average age is 2.34 years, with a predominance of males and children from urban areas. Hospitalization is high in August, September, and October, and diarrhea, vomiting, and anorexia predominate.

Unveiling the Evolutionary Impact of Artificial Intelligence on the Workforce

Unveiling the Evolutionary Impact of Artificial Intelligence on the Workforce

Fitness Effects of Phenotypic Mutations at Proteome-Scale Reveal Optimality of Translation Machinery.

Errors in protein translation can lead to non-genetic, phenotypic mutations, including amino acid misincorporations. While phenotypic mutations can increase protein diversity, the systematic characterization of their proteome-wide frequencies and their evolutionary impact has been lacking. Here, we developed a mechanistic model of translation errors to investigate how selection acts on protein populations produced by amino acid misincorporations. We fitted the model to empirical observations of misincorporations obtained from over a hundred mass spectrometry datasets of E. coli and S. cerevisiae. We found that on average 20% to 23% of proteins synthesized in the cell are expected to harbor at least one amino acid misincorporation, and that deleterious misincorporations are less likely to occur. Combining misincorporation probabilities and the estimated fitness effects of amino acid substitutions in a population genetics framework, we found 74% of mistranslation events in E. coli and 94% in S. cerevisiae to be neutral. We further show that the set of available synonymous tRNAs is subject to evolutionary pressure, as the presence of missing tRNAs would increase codon-anticodon cross-reactivity and misincorporation error rates. Overall, we find that the translation machinery is likely optimal in E. coli and S. cerevisiae and that both local solutions at the level of codons and a global solution such as the tRNA pool can mitigate the impact of translation errors. We provide a framework to study the evolutionary impact of codon-specific translation errors and a method for their proteome-wide detection across organisms and conditions.

The evolutionary impact of childhood cancer on the human gene pool

Germline pathogenic variants associated with increased childhood mortality must be subject to natural selection. Here, we analyze publicly available germline genetic metadata from 4,574 children with cancer [11 studies; 1,083 whole exome sequences (WES), 1,950 whole genome sequences (WGS), and 1,541 gene panel] and 141,456 adults [125,748 WES and 15,708 WGS]. We find that pediatric cancer predisposition syndrome (pCPS) genes [n = 85] are highly constrained, harboring only a quarter of the loss-of-function variants that would be expected. This strong indication of selective pressure on pCPS genes is found across multiple lines of germline genomics data from both pediatric and adult cohorts. For six genes [ELP1, GPR161, VHL and SDHA/B/C], a clear lack of mutational constraint calls the pediatric penetrance and/or severity of associated cancers into question. Conversely, out of 23 known pCPS genes associated with biallelic risk, two [9%, DIS3L2 and MSH2] show significant constraint, indicating that they may monoallelically increase childhood cancer risk. In summary, we show that population genetic data provide empirical evidence that heritable childhood cancer leads to natural selection powerful enough to have significantly impacted the present-day gene pool.

Disenfranchised DNA: biochemical analysis of mutant øX174 DNA-binding proteins may further elucidate the evolutionary significance of the unessential packaging protein A.

Most icosahedral DNA viruses package and condense their genomes into pre-formed, volumetrically constrained capsids. However, concurrent genome biosynthesis and packaging are specific to single-stranded (ss) DNA micro- and parvoviruses. Before packaging, ~120 copies of the øX174 DNA-binding protein J interact with double-stranded DNA. 60 J proteins enter the procapsid with the ssDNA genome, guiding it between 60 icosahedrally ordered DNA-binding pockets formed by the capsid proteins. Although J proteins are small, 28-37 residues in length, they have two domains. The basic, positively charged N-terminus guides the genome between binding pockets, whereas the C-terminus acts as an anchor to the capsid's inner surface. Three C-terminal aromatic residues, W30, Y31, and F37, interact most extensively with the coat protein. Their corresponding codons were mutated, and the resulting strains were biochemically and genetically characterized. Depending on the mutation, the substitutions produced unstable packaging complexes, unstable virions, infectious progeny, or particles packaged with smaller genomes, the latter being a novel phenomenon. The smaller genomes contained internal deletions. The juncture sequences suggest that the unessential A* (A star) protein mediates deletion formation.IMPORTANCEUnessential but strongly conserved gene products are understudied, especially when mutations do not confer discernable phenotypes or the protein's contribution to fitness is too small to reliably determine in laboratory-based assays. Consequently, their functions and evolutionary impact remain obscure. The data presented herein suggest that microvirus A* proteins, discovered over 40 years ago, may hasten the termination of non-productive packaging events. Thus, performing a salvage function by liberating the reusable components of the failed packaging complexes, such as DNA templates and replication enzymes.

Abstract PR012: Evolutionary dynamics of whole-genome doubling in ovarian cancer

Abstract Chromosomal instability (CIN) is a major driver of tumor progression and treatment resistance in many cancers. CIN is characterized by ongoing chromosome missegregation, segmental aneuploidy and whole-genome doubling (WGD), generating copy number heterogeneity that provides a substrate for natural selection. Although well characterized in model systems, the evolutionary dynamics and genomic impact of WGD is underexplored in primary tumors and metastases. Newly developed single-cell genomics assays now allow for the measurement of the whole genomes of single cells obtained from patient tissues, thus providing a direct view into the evolution of tumor genomes undergoing WGD. We performed multi-region single-cell whole genome sequencing (scWGS) in a cohort of patients with high-grade serous ovarian cancer (HGSOC), an archetype of high CIN cancers. We profiled a total of 70,644 single cells from 63 pre-treatment samples obtained for 36 HGSOC patients. For each patient, we computed total and allele-specific copy number per cell, and inferred the evolutionary history of each patient’s tumor, including clonal and subclonal WGD events and cell-specific whole-chromosome or arm-level copy number changes indicative of missegregations. To determine the role of CIN-associated micronuclei (MN) formation, we used high-resolution cGAS immunofluorescence (IF) microscopy to profile FFPE tissues site-matched to scWGS, and quantify spatially-resolved rates of MN formation and rupture across 120 samples. A majority of tumors were characterized by early clonal WGD (61%, 22/36 cases). The remaining patients exhibited subclonal WGD subpopulations averaging 10% of cancer cells in total. To understand the interplay between recent WGD and CIN across the cohort, we subset all patients cells into non-WGD, subclonal WGD, and clonal WGD and computed mis-segregation rates for these subsets. Non-WGD cells showed the lowest levels of mis-segregation. Subclonal WGD exhibited the highest CIN rates, including mis-segregation and multipolar cells indicative of CIN following a recent WGD event. Clonal WGD exhibited intermediate levels of mis-segregation indicative of stabilization following a historical WGD event. CIN following WGD often resulted in a reduction in ploidy relative to the ancestral WGD cell. Micronucleus rupture was ubiquitously detected in IF across HGSOC tumors, and MN rates varied widely between patients and across primary and metastatic sites. Micronucleus rupture commonly resulted from the impact of WGD, which increased sequestration of missegregated chromosomes into MN. Through multimodal single cell measurements of HGSOC tumors, we were able to characterize genomic complexity from individual cell division errors in HGSOC, and shed light into how the transient processes governing ovarian cancer cell evolution impact the genomes of cell populations. Citation Format: Ignacio Vázquez-García, Matthew Myers, Marc J. Williams, Samuel S. Freeman, Jun Li, Hongyu Shi, Gryte Satas, Nicholas Ceglia, Florian Uhlitz, MSK SPECTRUM Consortium, Britta Weigelt, Dmitriy Zamarin, Andrew McPherson, Samuel F. Bakhoum, Sohrab P. Shah. Evolutionary dynamics of whole-genome doubling in ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Translating Cancer Evolution and Data Science: The Next Frontier; 2023 Dec 3-6; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_2):Abstract nr PR012.

Genome-wide mining of diversity and evolutionary signatures revealed selective hotspots in Indian Sahiwal cattle

The Sahiwal cattle breed is the best indigenous dairy cattle breed, and it plays a pivotal role in the Indian dairy industry. This is due to its exceptional milk-producing potential, adaptability to local tropical conditions, and its resilience to ticks and diseases. The study aimed to identify selective sweeps and estimate intrapopulation genetic diversity parameters in Sahiwal cattle using ddRAD sequencing-based genotyping data from 82 individuals. After applying filtering criteria, 78,193 high-quality SNPs remained for further analysis. The population exhibited an average minor allele frequency of 0.221 ± 0.119. Genetic diversity metrics, including observed (0.597 ± 0.196) and expected heterozygosity (0.433 ± 0.096), nucleotide diversity (0.327 ± 0.114), the proportion of polymorphic SNPs (0.726), and allelic richness (1.323 ± 0.134), indicated ample genomic diversity within the breed. Furthermore, an effective population size of 74 was observed in the most recent generation. The overall mean linkage disequilibrium (r2) for pairwise SNPs was 0.269 ± 0.057. Moreover, a greater proportion of short Runs of Homozygosity (ROH) segments were observed suggesting that there may be low levels of recent inbreeding in this population. The genomic inbreeding coefficients, computed using different inbreeding estimates (FHOM, FUNI, FROH, and FGROM), ranged from −0.0289 to 0.0725. Subsequently, we found 146 regions undergoing selective sweeps using five distinct statistical tests: Tajima's D, CLR, |iHS|, |iHH12|, and ROH. These regions, located in non-overlapping 500 kb windows, were mapped and revealed various protein-coding genes associated with enhanced immune systems and disease resistance (IFNL3, IRF8, BLK), as well as production traits (NRXN1, PLCE1, GHR). Notably, we identified interleukin 2 (IL2) on Chr17: 35217075–35223276 as a gene linked to tick resistance and uncovered a cluster of genes (HSPA8, UBASH3B, ADAMTS18, CRTAM) associated with heat stress. These findings indicate the evolutionary impact of natural and artificial selection on the environmental adaptation of the Sahiwal cattle population.

Resistance against two lytic phage variants attenuates virulence and antibiotic resistance in Pseudomonas aeruginosa.

Bacteriophage therapy is becoming part of mainstream Western medicine since antibiotics of clinical use tend to fail. It involves applying lytic bacteriophages that self-replicate and induce cell lysis, thus killing their hosts. Nevertheless, bacterial killing promotes the selection of resistant clones which sometimes may exhibit a decrease in bacterial virulence or antibiotic resistance. In this work, we studied the Pseudomonas aeruginosa lytic phage φDCL-PA6 and its variant φDCL-PA6α. Additionally, we characterized and evaluated the production of virulence factors and the virulence in a Galleria mellonella model of resistant mutants against each phage for PA14 and two clinical strains. Phage φDCL-PA6α differs from the original by only two amino acids: one in the baseplate wedge subunit and another in the tail fiber protein. According to genomic data and cross-resistance experiments, these changes may promote the change of the phage receptor from the O-antigen to the core lipopolysaccharide. Interestingly, the host range of the two phages differs as determined against the Pseudomonas aeruginosa reference strains PA14 and PAO1 and against nine multidrug-resistant isolates from ventilator associated pneumonia. We show as well that phage resistance impacts virulence factor production. Specifically, phage resistance led to decreased biofilm formation, swarming, and type III secretion; therefore, the virulence towards Galleria mellonella was dramatically attenuated. Furthermore, antibiotic resistance decreased for one clinical strain. Our study highlights important potential advantages of phage therapy's evolutionary impact that may be exploited to generate robust therapy schemes.

Viral mimicry and endocrine system: Divulging the importance in host-microbial crosstalk.

Host-pathogen interactions are complex associations which evolve over long co-evolutionary histories. Pathogens exhibit different mechanisms to gain advantage over their host. Mimicry of host factors is an influential tool in subverting host mechanisms to ensure pathogenesis. This chapter discusses such molecular mimicry exhibited during viral infections. Understanding the evolutionary relationships, shared identity and functional impact of the virus encoded mimics is critical. With a particular emphasis on viral mimics and their association with cancer and autoimmune diseases, this chapter highlights the importance of molecular mimicry in virus biology.

Evolution prediction method for electric private car ownership considering the decision-making behaviour of consumers

A global consensus has been reached that promotes full electrification in the automotive field to solve environmental problems, and Electric Vehicles (EVs) have developed rapidly in recent years. China has gradually promoted electrification for taxis, trucks, and private cars. Due to the large number of electric private cars (EPCs), the evolutionary impact of EPC ownership on the charging demand and even the power grid at different stages cannot be ignored. But the evolution of EPC ownership is affected by many factors, and the prediction accuracy is low. Thus, an evolution prediction method of EPC ownership considering the decision-making behaviour of consumers is proposed. Firstly, considering the mutual influence of the individual mental state of consumers for EPC, the social network of consumers is generated based on the small-world network model. Secondly, to simulate the psychological state of consumers and decision-making behaviour, a consumer-state decision model is built based on the Markov chain. Considering the influence of multiple factors on the individual decision-making behaviour of consumers, transfer indicators are constructed to quantify the transfer of states of consumers. Then, combined with the historical data, the development of EPC ownership is predicted. Finally, the effectiveness of the prediction method is verified based on the Shanghai EPC ownership. Compared with other methods, the prediction accuracy of the proposed method is improved by 6.4%, and the evolution of EPC ownership in Chinese different regions can be quantified to provide a basis for related research.

Intermediate mass black hole feedback in dwarf galaxy simulations with a resolved ISM and accurate nuclear stellar dynamics

AbstractRecent observations have established that dwarf galaxies can host black holes of intermediate mass (IMBH, 100Mȯ < MIMBH ≲ 105 Mȯ). With modern numerical models, we can test the growth of IMBHs as well as their evolutionary impact on the host galaxy. Our novel subsolar-mass (0.8 solar mass) resolution simulations of dwarf galaxies (M* = 2 × 107 Mȯ) have a resolved three-phase interstellar medium and account for non-equilibrium heating, cooling, and chemistry processes. The stellar initial mass function is fully sampled between 0.08–150 Mȯ while massive stars can form HII regions and explode as resolved supernovae. The stellar dynamics around the IMBH is integrated accurately with a regularization scheme. We present a viscous accretion disk model for the IMBH with momentum, energy, and mass conserving wind feedback. We demonstrate how the IMBH can grow from accretion of the cold and warm gas phase and how the presence of the IMBH and its feedback impacts the gas phase structure.