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At least 19 recordsLinked to original sources
PubMed1979

Molecular clocks, molecular profiles, and optimum diets: three approaches to the problem of aging.

It has been hypothesized that the deamidation of glutaminyl and asparaginyl residues serves as a molecular clock for many biological processes including protein turnover, development, and aging. At present, this hypothesis has passed some experimental tests which are necessary but not sufficient for its acceptance. The current state of evidence about deamidation as a molecular clock is discussed. In addition, since the molecular biology of aging, especially in humans, is only partly understood, it is of value to develop quantitative, empirical measures of physiological human age and to use these measures to evaluate alternative human living conditions, especially easily adopted alternatives like variations in diet. This may allow some decrease in the suffering and loss from human aging until such time as molecular biology provides superior and more intellectually satisfying answers. An empirical system which consists of quantitative measurement of several hundred human chemical constituents followed by computerized pattern recognition is described. It is hoped that this system will eventually become an aid in the minimization of the rate of human aging through changes in diet and other factors.

Adult↗
PubMed2025

Detecting Introgression in Shallow Phylogenies: How Minor Molecular Clock Deviations Lead to Major Inference Errors.

Recent theoretical and algorithmic advances in introgression detection, coupled with the growing availability of genome-scale data, have highlighted the widespread occurrence of interspecific gene flow across the tree of life. However, current methods largely depend on the molecular clock assumption-a questionable premise given empirical evidence of substitution rate variation across lineages. While such rate heterogeneity is known to compromise gene flow detection among divergent lineages, its impact on closely related taxa at shallow evolutionary timescales remains poorly understood, likely because these taxa are often assumed to adhere to a molecular clock. To address this gap, we combine theoretical analyses and simulations to evaluate the robustness of widely used site pattern methods (D-statistic and HyDe) to rate variation across phylogenetic timescales. Our results demonstrate that both methods exhibit high sensitivity to even minor deviations from the molecular clock at shallow timescales, complementing previous findings at deeper scales. Specifically, in young phylogenies (with an age of 3 × 105 generations) with small population sizes, weak (17% difference) and moderate (33% difference) rate variation can inflate false-positive rates up to 35% and 100%, respectively, using site pattern counts from a 500 Mb genome. Employing a more distant outgroup intensifies these spurious signals. Our study demonstrates that summary tests for introgression are pervasively vulnerable to minor rate variations and underscores the critical need for advanced methodologies to disentangle genuine introgression from false signals generated by rate heterogeneity.

Phylogeny↗
PubMed2026

On the origin of animals and placental mammals: a critique of literalist readings of the fossil record.

The fossil record is incomplete, as evidenced by the pervasive presence of ghost lineages throughout the Tree of Life. For example, across placental mammals, at least 720 Myr of basal lineages are ghost lineages, that is, lineages that have left no fossil evidence of their past history. In contrast, some studies have suggested that the fossil record is a faithful temporal archive of evolutionary history and thus the times of diversification of clades must be close to the ages of their oldest fossils. Such literalist interpretations have been contradicted by analysis of molecular datasets which, in many cases, indicate that groups including placental mammals and animals may have originated at times substantially older than their fossil records. Some of those studies have further argued that, in the case of animals and placental mammals, molecular clocks are uninformative, suffer from characteristic pathologies, and thus cannot distinguish between recent and ancient hypotheses of diversification. Here, we reexamine these two cases and show, using Bayesian model selection theory, that the explosive diversification models previously proposed for animals and placental mammals have a posterior probability of ∼0. We show the characteristic pathologies purportedly discovered do not exist, highlight errors in previous analyses, and provide advice on best practice for molecular-clock dating analysis.

Animals↗
PubMed2024

The evolution of cnidarian stinging cells supports a Precambrian radiation of animal predators.

Cnidarians-the phylum including sea anemones, corals, jellyfish, and hydroids-are one of the oldest groups of predatory animals. Nearly all cnidarians are carnivores that use stinging cells called cnidocytes to ensnare and/or envenom their prey. However, there is considerable diversity in cnidocyte form and function. Tracing the evolutionary history of cnidocytes may therefore provide a proxy for early animal feeding strategies. In this study, we generated a time-calibrated molecular clock of cnidarians and performed ancestral state reconstruction on 12 cnidocyte types to test the hypothesis that the original cnidocyte was involved in prey capture. We conclude that the first cnidarians had only the simplest and least specialized cnidocyte type (the isorhiza) which was just as likely to be used for adhesion and/or defense as the capture of prey. A rapid diversification of specialized cnidocytes occurred through the Ediacaran (~654-574 million years ago), with major subgroups developing unique sets of cnidocytes to match their distinct feeding styles. These results are robust to changes in the molecular clock model, and are consistent with growing evidence for an Ediacaran diversification of animals. Our work also provides insight into the evolution of this complex cell type, suggesting that convergence of forms is rare, with the mastigophore being an interesting counterexample.

Animals↗
PubMed2025

A Million Years of Mammoth Mitogenome Evolution.

The genomic study of specimens dating to the Early and Middle Pleistocene (EP and MP), a period spanning from 2.6 million years ago (Ma) to 126 thousand years ago (ka), has the potential to elucidate the evolutionary processes that shaped present-day biodiversity. Obtaining genomic data from this period is challenging, but mitochondrial DNA, given its higher abundance compared to nuclear DNA, could play an important role to understand evolutionary processes at this time scale. In this study, we report 34 new mitogenomes, including two EP and nine MP mammoth (Mammuthus spp.) specimens from Siberia and North America and analyze them jointly with >200 publicly available mitogenomes to reconstruct a transect of mammoth mitogenome diversity throughout the last million years. We find that our EP mitogenomes fall outside the diversity of all Late Pleistocene (LP) mammoths, while those derived from MP mammoths are basal to LP mammoth Clades 2 and 3, supporting an ancient Siberian origin of these lineages. In contrast, the geographical origin of Clade 1 remains unresolved. With these new deep-time mitogenomes, we observe diversification events across all clades that appear consistent with previously hypothesized MP and LP demographic changes. Furthermore, we improve upon an existing methodology for molecular clock dating of specimens >50 ka, demonstrating that specimens need to be individually dated to avoid biases in their age estimates. Both the molecular and analytical improvements presented here highlight the importance of deep-time genomic data to discover long-lost genetic diversity, enabling better assessments of evolutionary histories.

Animals↗
PubMed1979

The use of amino acid sequence analysis in assessing evolution.

The thirteen year history of assessing evolution by amino acid sequence analysis has made apparent the limitations imposed upon this system by the finite nature of the characters. This finiteness exists on several levels and ultimately expresses itself as parallelism, back mutation and the retention of primitive characters in the sequences of proteins from present day species and the putative ancestral protein chains. Sequence analysis shares these problems with other molecular approaches, but because it is concerned both with the nucleotide substitutions in the genome and with the functional roles of proteins, it has unique advantages. For example, the large fluctuation in the rate of fixation of mutations in a protein's evolution can be detected and used to point out the unreliability of any molecular clock for estimating divergence dates. Moreover, when consideration is given to studies which assign functional significance to specific amino acid sites in a protein, changes in function during the descent of a protein can be appreciated and their significance correlated with organismal evolution.

Amino Acid Sequence↗
PubMed2026

Evolution and Expression Divergence of Legume PAL Genes Suggest Associations with Drought Response and Root Nodule Development.

Comparative genomic analyses provide insight into the mechanisms underlying gene-family evolution and crop adaptation. Here, we used the legume phenylalanine ammonia-lyase (PAL) gene family as a model and integrated pan-genomic, phylogenetic, molecular evolutionary, duplication-mode, and transcriptomic analyses, while developing GFtool for gene family identification. Across 45 genomes, we identified 302 PAL genes and classified them into five Groups. Groups 1-3 represented ancient lineages shared with outgroups, whereas Groups 4 and 5 were legume-specific. Molecular-clock analyses placed the divergence of Group 2 near the Paleocene-Eocene transition, while Groups 4 and 5 diversified from the middle Eocene to the early Oligocene. WGD/segmental duplication broadly contributed to PAL copy-number expansion, whereas tandem duplication was enriched in Group 5 of Papilionoideae. Group 2 genes showed drought-induced expression, whereas Group 5 genes were associated with early root nodule development. GFtool provides a scalable framework for gene-family studies.

Fabaceae↗
PubMed2026

PyEvoMotion: a Python tool for population-based time-course analysis of genome evolution.

SUMMARY: We present PyEvoMotion, an open-source Python tool for inferring molecular clock models with time-dependent Gaussian noise from high-throughput genomic datasets. PyEvoMotion features a command-line interface and a modular architecture, allowing seamless integration into larger bioinformatic pipelines. The tool supports customizable filtering, temporal discretization definition, and mutation classification, making it adaptable to diverse research needs. While traditional phylogenetic methods may encounter computational challenges with large datasets, PyEvoMotion can process thousands to millions of sequences to compute statistical parameters associated with a stochastic differential equation model, thereby weighting the genetic variation within the population. Using viral genomic data, we demonstrate its capability to infer evolutionary rates and detect non-Brownian evolutionary motions with subdiffusive behavior. PyEvoMotion shows potential to provide overlooked insights into genome evolution in different contexts. AVAILABILITY AND IMPLEMENTATION: The open source software is available on GitHub at https://github.com/luksgrin/PyEvoMotion and on SourceForge at https://sourceforge.net/projects/pyevomotion.

Software↗
PubMed2026

Spatiotemporal patterns of Rift Valley fever virus in Africa: a retrospective genomic epidemiology and phylodynamic modelling study.

BACKGROUND: Rift Valley fever virus (RVFV) is a mosquito-borne zoonotic pathogen causing outbreaks in humans and ruminants across Africa and the Arabian Peninsula. Originally restricted to the Great Rift Valley, RVFV has expanded geographically, prompting its classification by WHO as a pathogen of pandemic potential. We investigated the evolutionary and spatial dynamics of RVFV across Africa. METHODS: We used genomic data generated at the International Livestock Research Institute Nairobi genomic laboratory (BioProject PRJNA1106221) and combined with publicly available datasets retrieved from the National Center for Biotechnology (NCBI) GenBank nucleotide database. In retrieving RVFV genome sequences from the NCBI GenBank, we applied the search terms "Rift Valley fever virus segment L AND 6404[SLEN]", "Rift Valley fever virus segment M AND 3885[SLEN]", and "Rift Valley fever virus segment S AND 1520:1690[SLEN]" for L (Large), M (Medium), and S (Small) segments, respectively. For sequences without additional spatiotemporal information, we searched PubMed to extract the associated sequence metadata. We performed molecular clock analysis, phylogenetic inference, phylodynamic modelling (continuous phylogeographic reconstruction), and landscape phylogeography on the three RVFV genome segments (L, M, and S). We aimed to assess evolutionary rates, dispersal patterns, and environmental drivers. Focus was placed on lineage C, the most widely distributed variant. FINDINGS: The global dataset used in this study consisted of large (n=236), medium (n=237), and small (n=247), which were further filtered to exclude potential reassortants and vaccine strains. Genome sequences retrieved from NCBI GenBank database comprised large (n=180), medium (n=184), and small (n=202). The genome sequences from retrospective human and livestock isolates comprised large (n=56), medium (n=53), and small (n=45) collected in Burundi (2018), Kenya (2007, 2018, 2019, 2021, and 2022), and Rwanda (2018 and 2022). Our dataset revealed that RVFV exhibited low overall genetic diversity. Lineage C, however, showed evidence of active evolution, with substitution rates ranging from 3·58 × 10-4 to 9·76 × 10-4 substitutions per site per year. This lineage probably originated in Zimbabwe in the mid-1970s and has since expanded across eastern and southern Africa. Phylogeographic reconstructions revealed rapid spread, with diffusion coefficients exceeding 50 000 km2 per year. INTERPRETATION: Lineage C appears capable of establishing endemic transmission in new regions, with ongoing diversification observed during interepidemic periods. These observations reinforce the value of continuous genomic surveillance, particularly during cryptic transmission phases when adaptive mutations might emerge. Although further evidence is needed, observed trends in climate variability and land-use change point to the potential benefit of targeted surveillance in settings that could be at increased risk, including urban centres and wetlands. FUNDING: This work was supported by the German Federal Ministry for Economic Cooperation and Development, the Rockefeller Foundation, and the Africa Centres for Disease Control and Prevention.

Rift Valley fever virus↗
PubMed2026

Resolving the "Yucca queretaroensis problem": Phylogenomic analysis of Yucca reveals the identity of an enigmatic species and the origin of an obligate pollination mutualism.

PREMISE: The genus Yucca is a group of ~50 species of woody monocots endemic to the North American arid regions. Their obligate pollination mutualism with yucca moths is considered a "textbook example" of coevolution and is hypothesized to have promoted rapid diversification. However, testing this hypothesis has been difficult due to uncertainty about the placement of a rogue taxon, Yucca queretaroensis, a rare endemic of the Sierra Gorda region of central Mexico. Past work placed this species in different positions within the Agavoideae, producing starkly different age estimates for Yucca (25 to 4 million years). METHODS: We generated new sequence capture data for 353 nuclear genes and for all coding regions of the plastid genome from wild-collected plants and samples included in previous studies to provide a new phylogeny and new age estimate for Yucca. RESULTS: The data presented here suggest that Y. queretaroensis is closely related to other species of Yucca. A relaxed molecular clock analysis of the plastid genome produced an estimated age for the genus of approximately 6.8 million years. CONCLUSIONS: The results resolve a mystery that has bedeviled evolutionary biologists for decades and provide a surprisingly young estimate for the age of Yucca, suggesting rapid diversification. The past difficulties in identifying the correct placement of Y. queretaroensis appear to be the product of laboratory errors, mistakes in field identification, and frequent hybridization with co-distributed taxa. The "Yucca queretaroensis problem" reaffirms the essential role for traditional botanical tools in phylogenomics.

ASTRAL↗
PubMed1979

Quantitative immunological studies of the albumins of several species of fire bellied toads, genus Bombina.

1. Rabbit antisera against purified serum albumin of Bombina bombina were used to study relationships between B. bombina, B. variegata, and B. orientalis. 2. Quantitative micro-complement fixation tests indicated the albumins of B. bombina from central Poland and Bulgaria were indistinguishable. The albumins from several populations of B. variegata differed very slightly from that of B. bombina. The albumin of B. orientalis was quite distinct from that of B. bombina. 3. Using albumin as a molecular clock, we estimated B. bombina and B. variegata diverged within the last million years, whereas the B. orientalis lineage diverged roughly 10-12 mil yr ago.

Animals↗
PubMed2026

Tn125-borne blaNDM-1 is decoupled from clonal background in a transcontinental Acinetobacter baumannii ST126/KL14 lineage.

BACKGROUND/OBJECTIVES: Carbapenem-resistant A. baumannii (CRAB) is a WHO Critical Priority pathogen. The blaNDM-1-carrying ST126/KL14 lineage has been independently reported from Vietnam (2015), Malaysia (2016), the USA (2023-2026), and Costa Rica (2024). Whether these geographically distinct reports represent a single transcontinental clone and through what mechanism blaNDM-1 disseminates has not been formally tested. METHODS: We performed comprehensive whole-genome reanalysis of the Vietnamese sentinel isolate DMS06669_L1 using three nested panels (n = 19, n = 138, and n = 609 Vietnamese A. baumannii genomes) and surveyed 429 plasmids extracted from 99 NDM-1 A. baumannii genomes retrieved from NCBI Pathogen Detection. RESULTS: Four ST126/KL14 isolates share high inter-regional average nucleotide identity (ANI; 99.77-99.92%) but wide intra-clade core-SNP distances (41-731 SNPs, well above the ∼20-40-SNP range typical of single-outbreak transmission clusters) and lack a significant molecular clock, consistent with a related transcontinental lineage rather than a single recent clone. NDM-1 plasmid evolution is statistically uncorrelated with chromosomal sequence type (Spearman ρ = 0.131, P = 0.573). At 609-strain population scale, under a fragmentation-aware detection criterion, all 41 blaNDM-1-carrying Vietnamese strains also carry ISAba125, with none carrying blaNDM-1 without it (Fisher exact test; Haldane-Anscombe-corrected OR ≈2.0 × 10³, 95% CI 1.2 × 10² to 3.4 × 10⁴; P = 4.74×10⁻⁴⁸; φ = 0.79). CONCLUSIONS: The blaNDM-1 dissemination pattern in this ST126/KL14 lineage is primarily consistent with Tn125 transposition acting alongside plasmid-borne spread. Standard MLST-based surveillance is insufficient; multi-level genomic monitoring - including chromosomal and plasmid-level detection of the Tn125/ISAba125 unit - is required to track this resistance threat.

A. baumannii↗
PubMed2024

Expansion of Oropouche virus in non-endemic Brazilian regions: analysis of genomic characterisation and ecological drivers.

BACKGROUND: Oropouche virus (OROV) is an arbovirus endemic in the Amazon region that closely resembles other arboviruses in terms of human disease, leading to potential misdiagnoses. The virus ecology has mostly restricted its occurrence to the Amazon biome; however, after a large 2023-24 OROV epidemic in the Brazilian Amazon region, outbreaks are being reported across Brazil and in other countries in Latin America. Here, we investigate the OROV spread outside Amazonia. METHODS: In this genomic and epidemiological study, OROV cases from January, 2023, to July, 2024, provided by the General Coordination of Public Health Laboratories of Brazil on Aug 1, 2024, were compared by geographical location (Amazon vs non-Amazon) and municipal population size, and a linear mixed model was employed to assess the relationship between agricultural area size and cases. OROV-positive samples from central laboratories of five non-Amazonian Brazilian states were sequenced using an amplicon-based approach. Bayesian phylogeographical analysis was performed with near full-length viral genomes, incorporating individual travel histories when relevant. The estimated dates of viral introductions in each sampled location were then contextualised with public epidemiological data. FINDINGS: Epidemic data show that outside the Amazon region, OROV cases frequency was 3&#xb7;9-times higher in small municipalities than in large municipalities. The planted areas of some agricultural products, such as banana plantations, were positively correlated (r=0&#xb7;39, p<0&#xb7;0001) with OROV cases. The linear mixed model revealed that, besides banana, cassava also has larger (p<0&#xb7;05) planted areas in municipalities with OROV cases when compared with those with no cases. The phylogenetic analysis of 32 new OROV genomes reconstructed multiple exportation events of the newly identified reassortant lineage from the Amazon to other Brazilian regions between January and March, 2024. At least three of the previously described OROV phylogenetic clades circulating in the Amazon were the source of viral introductions. Molecular clock analysis estimated that viral introductions happened from 50 days to 100 days before detecting the outbreaks in each state. INTERPRETATION: Our results confirm that the novel OROV reassortant lineage spread from the Amazon to other regions in early 2024, successfully establishing local transmission. The fact that outbreaks were observed in small municipalities, instead of large urban centres, suggests that local ecological conditions that are ideal for OROV vector occurrence, such as the banana plantation environment, might be important factors driving its spread in Brazil. FUNDING: DECIT, CNPq, FAPEAM, and Inova-Fiocruz. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.

Brazil↗
PubMed2024

Characterization of West Nile virus Koutango lineage from phlebotomine sandflies in Kenya.

The West Nile virus (WNV), primarily transmitted by mosquitoes, is one of the most widespread flaviviruses globally, with past outbreaks occurring in the USA and Europe. Recent studies in parts of Africa, including Kenya, have identified the West Nile virus Koutango lineage (WN-KOUTV) among phlebotomine sandfly populations, however, our understanding of this virus remains limited. This study aimed to characterize WN-KOUTV from phlebotomine sandflies. Sandflies were sampled between 12th -16th March 2021 and 16th -20th March 2023 from six villages each in Baringo and Isiolo Counties, using CDC light traps. Female sandflies were taxonomically identified and pooled based on genus and site of collection. Virus isolation was performed in Vero cells. Viral genomes were determined using next-generation sequencing. Phylogenetic and molecular clock analyses were done to decipher the virus's evolutionary relationships. Comparative analyses of amino acid sequences were performed to determine variations. Protein modeling in Pymol was conducted to elucidate variations in key protein regions. Evolutionary pressure analysis investigated the selection pressures on the virus. In vitro experiments were done to investigate the virus growth kinetics in mammalian Vero E6 and mosquito C6/36 cells. We report the isolation of WN-KOUTV from Salabani in Baringo and Aremet in Isiolo, Kenya. The isolated WN-KOUTVs clustered with previously identified WN-KOUTV strains. Comparative analysis revealed a unique amino acid at NS5 653. The WN-KOUTV lineage as a whole is under purifying selective pressure, with diversifying pressure acting at site NS3 267. The current WN-KOUTV replicated in Vero E6 and C6/36 cells comparable to West Nile virus Lineage 1a, isolated from mosquitoes. Subsequent isolations of WN-KOUTV in phlebotomine sandflies suggest potential vectors, however, vector competence studies would confirm this. Replication in mammalian and insect cell lines suggests there may exist a vector/host relationship. We speculate the close genetic relationship of WN-KOUTV strains from East and West Africa may potentially be enabled by bird migratory routes between the two regions. If proven, this could point to a potential future pandemic pathway for this virus.

Animals↗
PubMed2025

Refinement of Poultry Standing in Japan Based on Recent Anthropo-ornithological Perspectives.

Poultry meat and eggs are important sources of high-quality animal protein worldwide. However, poultry in Japan has historically been regarded as a symbolic or spiritual entity more than as a food source, as its roles are deeply embedded in Japanese consciousness and society. Current evidence indicates that chickens first appeared in Japan during the Yayoi period, approximately 2,000 years ago, coinciding with a period of active human migration to the Japanese archipelago. Since then, poultry has played notable roles in Japanese art, literature, mythology, and folktales. Recent advancements in molecular clock analysis or the detection of genomic modifications, such as introgression, deletions, mutations, and viral infection from trace fossil/live samples necessitate the continual revision and refinement of existing theories about human and animal history across several academic disciplines. Therefore, the objective of the present review was to elucidate the distinct and multilayered relationship between humans and poultry in Japan, incorporating recent anthropological and ornithological perspectives.

Anthropology↗
PubMed1976

Evolutionary processes and evolutionary noise at the molecular level. II. A selectionist model for random fixations in proteins.

On account, notably, of a competition between different component functions for individual sites in polypeptide chains, each protein molecule represents a functional compromise, with some functions optimized, but the overall state of the molecule "suboptimal". The proposal is made that the selection coefficient relating to a protein molecule under given conditions can in principle be broken down into partial selection coefficients relevant to the different functions that the molecule carries out. At general-function sites, each fixation improves some function, while others deteriorate, at first nonsignificantly, and the overall adaptive state of the molecule fluctuates around its maximum. A selective mechanism is described whereby kaleidoscopic changes in primary structure at variable sites are indefinitely promoted, independently of any environmental changes and with the molecule remaining close to a state of maximal overall adaptation. The paradoxical aspect of this proposal is analyzed. The implication of specific functions in substitutions at general-function sites is noted. Further, it is shown that a certain category of changes in the internal environment of the organism can be integrated into the constant-environmental model for selection. Genetic sufficiency is considered a notion more adequate than genetic optimality for describing biological fitness and for providing a basis for the present model. On this basis selection occurs without genetic load. Multipolymorphism is one of the consequences. Several lines of evidence, in particular observations on polymorphism in deep sea organisms, seem to support the model. It is pointed out that it provides a theoretical foundation for a molecular evolutionary clock. The theoretical constancy of the clock depends on the constancy of functional density. The question of the evolution of functional density is examined. Comparisons of observed substitution frequencies with values expected on a random basis are rejected as a measure of the contribution to evolution of nondetermination. They are considered to reflect a hierarchy in the resistance of the molecules to different amino acid residues as substituents. A limited component of "true" randomness, again accompanied by selection, is on the other hand provided by the model. Most amino acid substitutions are considered evolutionary noise, even though noise compatible with selection. It is proposed that evolutionary significant substitutions may be identified by monitoring changes in functional density and weighted functional density.

Alleles↗
PubMed2026

Replicating lipid micelles: a feasible precursor to the origin of life and the earliest appearance of genomes.

The most commonly accepted scenario of early Earth includes: creation of the universe around 13.8 Ga (Giga-annus; or 109 years ago); establishment of our solar system&#x2009;~&#x2009;4.60 Ga; and formation of Earth&#x2009;~&#x2009;4.54 Ga. The earliest life forms on our planet so far observed to have existed, are microbes that left signals of their presence in rocks&#x2009;~&#x2009;3.6 Ga - suggesting that Life forms existed within the first 940&#xa0;million years after Earth's formation. However, an intriguing recent publication [1] infers that the last universal common ancestor (LUCA) likely existed by 4.2 Ga, and that the inferred LUCA had a genome of at least 2.5&#xa0;Mb of DNA, encoding around 2,600 proteins; this suggests that sophisticated Life might have existed within the first 340&#xa0;million years after Earth was formed. The commonly accepted geological history of early Earth suggests that the turbulent Hadean Eon lasted until 4.0 Ga, with the Late Heavy Bombardment (LHB) period occurring around 4.1 to 3.8 Ga. If Earth during the Hadean exhibited a molten surface, intense volcanic activity, and constant bombardment by asteroids and comets - how were sensitive molecules (e.g., nucleic acids, proteins) able to survive? Considering the "Lipid First" hypothesis [2], we propose that replicating lipid micelles are feasible candidates for having populated much of Earth's deep hydrothermal vents and turbulent surface within the first 340&#xa0;million years of Earth's existence. These lipid micelles could therefore have provided a plausible form of "protective capsules" inside which early Life's sensitive molecules were able to evolve.

Origin of Life↗