@article{snyder1975a,
    author = "Snyder, W.D. and Fox, Sidney W.",
    title = "A model for the origin of stable protocells in a primitive alkaline ocean",
    year = "1975",
    journal = "Biosystems",
    url = "https://doi.org/10.1016/0303-2647(75)90029-5",
    doi = "10.1016/0303-2647(75)90029-5",
    number = "2",
    pages = "222-229",
    volume = "7"
}

@misc{snyder1975a2,
    author = "Snyder, W. D. and Fox, S",
    title = "A model for the origin of stable protocells in a primitive alkaline ocean",
    year = "1975",
    howpublished = "BioSystems, v. 7, p. 222-229",
    note = "talkorigins\_source = {true}; raw\_reference = {Snyder, W. D., and Fox, S., 1975, A model for the origin of stable protocells in a primitive alkaline ocean: BioSystems, v. 7, p. 222-229.}"
}

@article{fox1980the,
    author = "Fox, Sidney W.",
    title = "The origins of behavior in macromolecules and protocells",
    year = "1980",
    journal = "Comparative Biochemistry and Physiology Part B: Comparative Biochemistry",
    url = "https://doi.org/10.1016/0305-0491(80)90330-2",
    doi = "10.1016/0305-0491(80)90330-2",
    number = "3",
    pages = "423-436",
    volume = "67"
}

@misc{fox1980the1,
    author = "Fox, S. W",
    title = "The origins of behavior in macromolecules and protocells",
    year = "1980",
    howpublished = "Comparative Biochemistry and Physiology, v. 67B, p. 423-436",
    note = "talkorigins\_source = {true}; raw\_reference = {Fox, S. W., 1980, The origins of behavior in macromolecules and protocells: Comparative Biochemistry and Physiology, v. 67B, p. 423-436.}"
}

@article{doi101029jb094ib04p04497,
    author = "Lin, P. and Stern, R. and Bloomer, S.",
    title = "Shoshonitic volcanism in the Northern Mariana Arc: 2. Large‐ion lithophile and rare earth element abundances: Evidence for the source of incompatible element enrichments in intraoceanic arcs",
    year = "1989",
    journal = "Journal of Geophysical Research",
    abstract = "The Mariana‐Volcano‐Izu arc system extends 2400 km north to south and is an outstanding example of an intraoceanic magmatic arc. In spite of this, the system is poorly known because most of it is submarine. Volcanism is entirely submarine in the northernmost Mariana arc, between 20°40′ and 24°N. This is the Northern Seamount Province (NSP) and was the focus of a detailed marine geologic and geochemical study, with additional data drawn from adjacent arc segments to the north (Volcano arc) and south (Central Island Province (CIP) of the Mariana arc). Samples from 24 submarine volcanoes and three islands were analyzed for concentrations of K, Rb, Sr, Ba, and the rare earth elements (REE). These data show strong variations along the arc, being relatively depleted in the more mature, tholeiitic and low‐K calc‐alkaline volcanoes of the Volcano arc and the Mariana CIP, containing on average 6100 ppm K, 300 ppm Sr, 200 ppm Ba, and 6 ppm La. All of the NSP is enriched in large ion lithophile (LIL) and light rare earth elements (REE), particularly the northern half (26,000 ppm K, 700 ppm Sr, 900 ppm Ba, 47 ppm La); these lavas have strong shoshonitic affinities. These enrichments do not result from fractional crystallization of CIP‐type melts. The source responsible for these enrichments shares some features in common with Mariana CIP and Volcano arc sources: K/Rb and K/Ba in particular are similar (∼500 and ∼30, respectively). However, Ba/La, Sr/Nd, and (Ce/Yb)n change drastically, with Ba/La and Sr/Nd decreasing to mantle values with increasing LIL and LREE enrichment. The origin of the LIL and LREE enrichments in the NSP shoshonites does not result from variations in the behavior or composition of the subducted lithosphere. Melting occurs exclusively within the mantle wedge, and forward modeling of the REE patterns for all Mariana and Volcano arc lavas indicates that melt generation occurs within the stability field of spinel lherzolite, probably within the upper 40–50 km of the subarc asthenosphere. Lavas from the large volcanoes of the Mariana CIP and Volcano arc result from 10–20\% melting of spinel lherzolite, followed by varying amounts of low‐P fractional crystallization. Inferences based on REE forward models that the NSP shoshonites manifest very low (1\%) degrees of partial melting of LIL‐ and LREE‐enriched spinel lherzolite are inconsistent with observed similar concentrations in tholeiites and shoshonites of high field strength cations such as TiO 2 and Yb. Some of this inconsistency can be explained as resulting from source or melt mixing, with the NSP shoshonites being derived from a LIL‐ and LREE‐enriched source or melt, with Ba/La and La/Yb indistinguishable from that of ocean island basalts (OIB), while Mariana CIP and Volcano arc melts are derived from a depleted mild‐ocean ridge basalt‐like mantle that has been recharged with K, Rb, Sr, and Ba by hydrous fluids. These variations are interpreted as reflecting the evolution of the subarc asthenosphere, with a depletion in time resulting from the continuous extraction of basaltic melts.",
    url = "https://www.semanticscholar.org/paper/7ace39a2af75be3149a2e9c0baa0ae4dfec1b230",
    doi = "10.1029/JB094IB04P04497",
    is_oa = "true",
    number = "B4",
    pages = "4497-4514",
    semanticscholar_citation_count = "137",
    semanticscholar_id = "7ace39a2af75be3149a2e9c0baa0ae4dfec1b230",
    volume = "94"
}

@article{altstein1996the,
    author = "Altstein, Anatoly D.",
    title = "The origin of protocells",
    year = "1996",
    journal = "Origins of life and evolution of the biosphere",
    url = "https://doi.org/10.1007/bf02459879",
    doi = "10.1007/bf02459879",
    number = "3-5",
    pages = "477-478",
    volume = "26"
}

@incollection{maynardsmith1997the,
    author = "Maynard Smith, John and Szathmary, Eors",
    title = "The origin of protocells",
    year = "1997",
    booktitle = "The Major Transitions in Evolution",
    abstract = "Cellularization has the following main aspects that we have to explain: • The need for active (self-generated) compartmentation when metabolism is liberated from the surface. • The origin of membranogenic molecules and membranes. • The origin and mechanism of spontaneous protocell fission. • The transportation problem. Simple membranes are not ‘leaky’ enough to permit important nutrients to pass through. • Were the first protocells autotrophs or heterotrophs? The evolution of the first autocatalytic metabolic cycle. • The iron-sulphur world and the RNA world: are they mutually exclusive or complementary? • The problem of the origin of the two membranes of negibacteria, the most ancient existing group of organisms. • The origin of chromosomes and DNA synthesis. We shall discuss these problems in turn. As we discussed before, the prebiotic pizza has the ability to localize metabolites and genes. This is advantageous for two reasons: Reactants are kept in each other’s proximity, which ensures that reaction rates will be high enough and that important compounds do not drift away. Genes will interact, directly (e.g. by influencing each other’s replication) or indirectly (by catalysing steps of metabolism), only with their neighbours: selection will thus be able to ensure cooperation among genes that would otherwise compete against each other. Life liberated itself from surfaces a long time ago. Somehow, passive localization must have been replaced by an active process of membrane generation, maintenance and fission. The basic structure of contemporary biomembranes is as follows. There is a molecular bilayer of lipids, to which proteins are attached in various ways. The bilayer is formed because the membrane constituents are so-called amphipathic molecules: they have a hydrophilic head and a hydrophobic tail. Since the binding interaction of water with itself is much stronger than that between water and hydrophobic compounds, the latter are expelled by water as much as possible; this results in tails coming together. A simple sheet of bilayer would still be not at the energy minimum because its edges would be exposed to water. An energetically favourable solution is the formation of a lipid vesicle.",
    url = "https://doi.org/10.1093/oso/9780198502944.003.0011",
    doi = "10.1093/oso/9780198502944.003.0011"
}

@article{doi105860choice275511,
    author = "Bowes, D.",
    title = "The Encyclopedia of Igneous and Metamorphic Petrology",
    year = "2006",
    journal = "Choice Reviews Online",
    url = "https://www.semanticscholar.org/paper/1d1b21d0c37566c2fb61f369b6c6bc413f5c156b",
    doi = "10.5860/choice.27-5511",
    is_oa = "true",
    number = "10",
    pages = "27-5511-27-5511",
    semanticscholar_citation_count = "10",
    semanticscholar_id = "1d1b21d0c37566c2fb61f369b6c6bc413f5c156b",
    volume = "27"
}

@incollection{delbianco2012heterotrophic,
    author = "Del Bianco, Cristina and Mansy, Sheref S.",
    title = "Heterotrophic Model Protocells",
    year = "2012",
    booktitle = "Cellular Origin, Life in Extreme Habitats and Astrobiology",
    url = "https://doi.org/10.1007/978-94-007-2941-4\_35",
    doi = "10.1007/978-94-007-2941-4\_35",
    pages = "709-722"
}

@article{s253699c8c30baf6051e11157c43f6a3ee59a04703,
    author = "Ravasio, A. and Denound, Adrien and Brambrink, E. and Koenig, M. and Riley, D. and Kondo, Yoshihiko and David, R.",
    title = "Geochemical features of deep-sea sediment in the eastern Indian Ocean: the first report of the Indian REY-rich mud.",
    year = "2013",
    url = "https://www.semanticscholar.org/paper/53699c8c30baf6051e11157c43f6a3ee59a04703",
    is_oa = "true",
    semanticscholar_id = "53699c8c30baf6051e11157c43f6a3ee59a04703"
}

@article{s2c179e69cd5f2facfcca94062737d2eaa6875de67,
    author = "Shimoda, G. and Kogiso, T.",
    title = "Geochemical connection between HIMU-FOZO-PREMA: two-stage dehydration of oceanic crust with layered structure",
    year = "2015",
    journal = "Japan Geoscience Union",
    url = "https://www.semanticscholar.org/paper/c179e69cd5f2facfcca94062737d2eaa6875de67",
    is_oa = "true",
    semanticscholar_id = "c179e69cd5f2facfcca94062737d2eaa6875de67"
}

@article{west2017the,
    author = "West, Timothy and Sojo, Victor and Pomiankowski, Andrew and Lane, Nick",
    title = "The origin of heredity in protocells",
    year = "2017",
    journal = "Philosophical Transactions of the Royal Society B: Biological Sciences",
    abstract = "Here we develop a computational model that examines one of the first major biological innovations—the origin of heredity in simple protocells. The model assumes that the earliest protocells were autotrophic, producing organic matter from CO 2 and H 2. Carbon fixation was facilitated by geologically sustained proton gradients across fatty acid membranes, via iron–sulfur nanocrystals lodged within the membranes. Thermodynamic models suggest that organics formed this way should include amino acids and fatty acids. We assume that fatty acids partition to the membrane. Some hydrophobic amino acids chelate FeS nanocrystals, producing three positive feedbacks: (i) an increase in catalytic surface area; (ii) partitioning of FeS nanocrystals to the membrane; and (iii) a proton-motive active site for carbon fixing that mimics the enzyme Ech. These positive feedbacks enable the fastest-growing protocells to dominate the early ecosystem through a simple form of heredity. We propose that as new organics are produced inside the protocells, the localized high-energy environment is more likely to form ribonucleotides, linking RNA replication to its ability to drive protocell growth from the beginning. Our novel conceptualization sets out conditions under which protocell heredity and competition could arise, and points to where crucial experimental work is required. This article is part of the themed issue ‘Process and pattern in innovations from cells to societies’.",
    url = "https://doi.org/10.1098/rstb.2016.0419",
    doi = "10.1098/rstb.2016.0419",
    number = "1735",
    pages = "20160419",
    volume = "372"
}

@article{doi1010079783319391939,
    author = "Marshall, C. and Fairbridge, R.",
    title = "Encyclopedia of Geochemistry",
    year = "2019",
    journal = "Elements",
    booktitle = "Encyclopedia of Earth Sciences Series",
    url = "https://link.springer.com/content/pdf/bfm:978-1-4020-4496-0/1",
    doi = "10.1007/978-3-319-39193-9",
    is_oa = "true",
    semanticscholar_citation_count = "82",
    semanticscholar_id = "0bb66a022e4fec0e87016d124c1d76c1891cc1cd"
}

@article{doi101038s415590191015y,
    author = "Jordan, S. and Rammu, Hanadi and Zheludev, I. and Hartley, Andrew M. and Maréchal, A. and Lane, N.",
    title = "Promotion of protocell self-assembly from mixed amphiphiles at the origin of life",
    year = "2019",
    journal = "Nature Ecology \& Evolution",
    url = "https://eprints.bbk.ac.uk/id/eprint/29841/1/Jordan\%20Lane\%20Nat\%20Ecol\%20Evol\%20accepted\%20MS\%202019.pdf",
    doi = "10.1038/s41559-019-1015-y",
    is_oa = "true",
    number = "12",
    pages = "1705-1714",
    semanticscholar_citation_count = "135",
    semanticscholar_id = "529845b10dfcd984d7f2d1cb6d38c6230a73b884",
    volume = "3"
}

@incollection{crossref2020mount,
    title = "Mount St. Helens",
    year = "2020",
    booktitle = "Out of the Crater",
    url = "https://doi.org/10.2307/j.ctv173f0jk.14",
    doi = "10.2307/j.ctv173f0jk.14",
    pages = "89-103"
}

@article{doi101021acslangmuir0c02258s001,
    author = "Misuraca, Loreto and Caliò, A. and Grillo, I. and Grélard, A. and Oger, P. and Peters, J. and Demé, B.",
    title = "High-Temperature Behavior of Early Life Membrane Models.",
    year = "2020",
    journal = "Langmuir : the ACS journal of surfaces and colloids",
    abstract = "Origin of life scenarios generally assume an onset of cell formation in terrestrial hot springs or in the deep oceans close to hot vents, where energy was available for non-enzymatic reactions. Membranes of the protocells had therefore to withstand extreme conditions different from what is found on the Earth surface today. We present here an exhaustive study of temperature stability up to 80 °C of vesicles formed by a mixture of short-chain fatty acids and alcohols, which are plausible candidates for membranes permitting the compartmentalization of protocells. We confirm that the presence of alcohol has a strong structuring and stabilizing impact on the lamellar structures. Moreover and most importantly, at a high temperature (> 60 °C), we observe a conformational transition in the vesicles, which results from vesicular fusion. Because all the most likely environments for the origin of life involve high temperatures, our results imply the need to take into account such a transition and its effect when studying the behavior of a protomembrane model.",
    url = "https://hal.archives-ouvertes.fr/hal-02988681/file/2020\%20Misuraca\%20Langmuir.pdf",
    doi = "10.1021/acs.langmuir.0c02258.s001",
    is_oa = "true",
    semanticscholar_citation_count = "13",
    semanticscholar_id = "483718267092c2834984252a0d4cc869ce9cbf4a"
}

@article{spustova2021protocells,
    author = "Spustova, Karolina and Köksal, Elif Senem and Ainla, Alar and Gözen, Irep",
    title = "Protocells: Subcompartmentalization and Pseudo‐Division of Model Protocells (Small 2/2021)",
    year = "2021",
    journal = "Small",
    url = "https://doi.org/10.1002/smll.202170007",
    doi = "10.1002/smll.202170007",
    number = "2",
    volume = "17"
}

@misc{zhang2023passive,
    author = "Zhang, Stephanie J. and Lowe, Lauren A. and Anees, Palapuravan and Krishnan, Yamuna and Fai, Thomas G. and Szostak, Jack W. and Wang, Anna",
    title = "Passive endocytosis in model protocells",
    year = "2023",
    abstract = "Semipermeable membranes are a key feature of all living organisms. While specialized membrane transporters in cells can import otherwise impermeable nutrients, the earliest cells would have lacked a mechanism to import nutrients rapidly under nutrient-rich circumstances. Using both experiments and simulations, we find that a process akin to passive endocytosis can be recreated in model primitive cells. Molecules that are too impermeable to be absorbed can be taken up in a matter of seconds in an endocytic vesicle. The internalized cargo can then be slowly released over hours, into the main lumen or putative cytoplasm. This work demonstrates a way by which primitive life could have broken the symmetry of passive permeation prior to the evolution of protein transporters.",
    url = "https://doi.org/10.1101/2023.01.07.522792",
    doi = "10.1101/2023.01.07.522792"
}

@article{doi101016jjcis202407045,
    author = "Guo, Dong and Zhang, Ziyue and Sun, Jichao and Hou, Wanguo and Du, N.",
    title = "A primitive cell model involving Vesicles, microtubules and asters.",
    year = "2024",
    journal = "Journal of colloid and interface science",
    abstract = "HYPOTHESIS
Simple single-chain amphiphiles (sodium monododecyl phosphate, SDP) and organic small molecules (isopentenol, IPN), both of primitive relevance, are proved to have been the building blocks of protocells on the early Earth. How do SDP-based membrane and coexisting IPN come together in specific ways to produce more complex chemical entities? What kind of cell-like behavior can be endowed with this protocell model? These are important questions in the pre-life chemical origin scenario that have not been answered to date.


EXPERIMENTS
The phase behavior and formation mechanism of the aggregates for SDP/IPN/H2O ternary system were characterized and studied by different electron microscopy, fluorescent probe technology, DLS, IR, ESI-MS, SAXS, etc. The stability (freeze-thaw and wet-dry treatments) and cell-like behavior (chemical signaling communication) were tested via simulating particular scenarios.


FINDINGS
Vesicles, microtubules and asters phases resembling the morphology and structure of modern cells/organelles were obtained. The intermolecular hydrogen bonding is the main driving force for the emergence of the aggregates. The protocell models not only display remarkable stabilities by simulating the primordial Earth's diurnal temperature differences and ocean tides but also are able to exhibit cell-like behavior of chemical signaling transition.",
    url = "https://www.semanticscholar.org/paper/3192f174f8e032578c951ffb4f89c41eff0be07f",
    doi = "10.1016/j.jcis.2024.07.045",
    is_oa = "true",
    pages = "700-711",
    semanticscholar_citation_count = "1",
    semanticscholar_id = "3192f174f8e032578c951ffb4f89c41eff0be07f",
    volume = "675"
}

@book{serra2025protocells,
    author = "Serra, Roberto and Villani, Marco",
    title = "Protocells and the Origin of Life",
    year = "2025",
    booktitle = "The Frontiers Collection",
    url = "https://doi.org/10.1007/978-3-031-91763-9",
    doi = "10.1007/978-3-031-91763-9"
}