Topics — What a work is about. Nucleation holds whatever reading the owner files here, whether or not an Anthology of the SOTA topic could also hold it; instruction for ML practice belongs to the anthology (ADR-048). The words are seeded from the clusters the reading-time triage of 2026-09-25 found, and grow by decision.
Endosymbiosis and reductive evolution — how one organism comes to live inside another and depend on it, and how that ends — reductive genome evolution by drift, deletional bias or adaptive loss (including the Black Queen dependencies of free-living microbes), complementary loss across partners, nested symbioses and symbiont splitting and replacement, endosymbiotic gene transfer, protein import and host control of transmission, organellogenesis and organelle loss, and eukaryogenesis. The ecology of a partnership is ecology (ADR-055).
31 of 1352 THEORY documents. Back to the full index.
| # | Title | Summary | Status |
|---|---|---|---|
| THEORY-1048 v2 | On the Black Queen Hypothesis of Morris, Lenski and Zinser, losing a costly function whose product leaks to neighbours is favoured by ordinary individual selection in large free-living microbial populations, and the loss proceeds until the remaining producers just supply the community, so that most cells come to depend on a rare few with no relatedness, cooperation or collective required | Morris, Lenski & Zinser (2012), LIT-1568, read in NOTE-1212. A loss-of-function mutant invades when its resource saving B = (Q_A − Q_M)/Q_A exceeds its cost C, which falls as other cells’ leaky activity protects it. Because protection falls as producers become rare, the loss is frequency dependent and stops short of community-wide loss. The evidence is Prochlorococcus’s loss of katG and its dependence on a peroxide-removing community. The dependence it produces is one-way, from beneficiaries to helpers, and involves no collective. | Active |
| THEORY-1049 v3 | On McCutcheon and colleagues’ survey, bacterial endosymbionts lose their own cell-envelope and envelope-transport genes together below about 400 kb, and begin to lose translation genes (ribosomal proteins, tRNAs, aminoacyl-tRNA synthetases) below about 200 kb, so that the smallest-genome symbionts cannot be self-sufficient and their membranes, transport and protein synthesis are presumably supplied by the host, as for organelles | McCutcheon, Garber, Spencer & Warren (2024), LIT-1571, read in NOTE-1213. The envelope goes first, near 400 kb, and translation starts to go below about 200 kb, the authors’ “tipping point”. Such symbionts have three-membrane envelopes and among the most biased proteomes in bacteria. They can only work if the host provides what they no longer encode. The host’s role is inferred, not shown: the mechanisms are, in the paper’s word, mysteries. | Active |
| THEORY-1050 v2 | In Athreya, Czuppon and Gokhale’s adaptive-dynamics model of an incipient endosymbiosis, mutual dependence (the product of the partners’ obligacies) evolves ahead of reproductive cohesion (the product of their adhesions) early on, but only under the mapping in which each partner’s free-living growth depends on its own obligacy alone while dissociation depends on both partners’ adhesions; the authors’ own appendix shows the bias vanishing under matched mappings and reversing under the opposite one, and their survey of real symbioses cannot test it | Athreya, Czuppon & Gokhale (2025), LIT-1570, read in NOTE-1211. In the exponential version of the model, all four traits rise monotonically. Each partner becomes more obligate than adhesive, because a gain in adhesion is “damped by the other adhesion” in the dissociation rate. Table S1 shows this is a consequence of that mapping: matched mappings give no bias, and the opposite mapping biases trajectories towards cohesion. The record’s summary of the result, “even when investments are uncorrelated”, is true of the traits’ genetic correlation but not of their functional coupling, which is what decides it. | Active |
| THEORY-1051 v2 | In Athreya, Czuppon and Gokhale’s model of an incipient endosymbiosis, the partner with the larger and faster-growing population evolves faster and becomes fully obligate first, which the authors read as a Red King effect in which the collective’s shared fate aligns interests; with equal within-collective rates for both partners, the other partner’s dependence then stays where it was, rises to full dependence, or falls to none, according to whether partners are born or die inside the collective; and in its simulations dependence rose from zero at the higher collective carrying capacities tried and not at the lowest, under a condition the authors show sufficient and not necessary, so a full transition to a mutually dependent, co-reproducing pair is a parameter-dependent outcome and not the default | Athreya, Czuppon & Gokhale (2025), LIT-1570, read in NOTE-1211. With the symbiont’s population larger and faster, its obligacy reaches 1 first. In the base model the host’s R₀ is then exactly 1, so host obligacy is neutral. With within-collective deaths the host goes fully obligate, and with within-collective births it goes back to independence. Obligacy rose from zero in simulations where the collective’s carrying capacity exceeded about aK_HK_S/d, a condition shown sufficient, not necessary; collective growth rate does not matter. The authors take the model as a null: a transition “is far from an inevitable outcome of the existence of a higher level of selection”. | Active |
| THEORY-1098 v2 | On Karnkowska and colleagues’ genome analysis, the oxymonad Monocercomonoides exilis lost its mitochondrion only after the organelle’s essential functions had been removed one by one, Fe–S cluster assembly to a bacterial-type SUF system shared with mitochondriate relatives and then the glycine cleavage system by loss, and the loss left the rest of the cell canonical, with no compensating changes found | Karnkowska et al. (2019), LIT-1574, read in NOTE-1243. The SUF replacement of the mitochondrial Fe–S pathway is shared by all examined Preaxostyla, including relatives that keep a mitochondrion-related organelle, and those relatives’ organelle still houses the glycine cleavage system that M. exilis lacks. So the organelle lost its jobs in at least two steps before it was lost. Apart from the mitochondrion, peroxisomes and mitophagy, the cell’s systems are those of an ordinary eukaryote. The order is inferred, not dated, and absence is limited by annotation. | Active |
| THEORY-1099 v2 | On Kay and colleagues’ relaxed-clock dating of pre-LECA gene duplications, most duplications in eukaryotic gene families of archaeal origin, including actin, tubulin, vesicle-trafficking and nuclear-targeted families, predate the onset of duplications in genes of alphaproteobacterial origin at about 2.2 billion years ago, which the authors take as the start of mitochondrial endosymbiosis, so the host was elaborating its cytoskeleton, endomembranes and nuclear machinery before the mitochondrion; each date is a maximum age for its paralogues’ functions, many intervals reach below 2.2 billion years, and the order of phagocytosis and the mitochondrion is left open | Kay et al. (2026), LIT-1566, read in NOTE-1234. A dated species tree places nFECA at 3.05–2.79 Ga, mFECA at 2.37–2.13 Ga and LECA at 1.80–1.67 Ga. Against an endosymbiosis marker at about 2.2 Ga, 85% of archaeal-origin duplications are older, and most non-alphaproteobacterial bacterial duplications are younger. The authors reject mitochondria-early scenarios and argue against serial endosymbiosis. The sharp edges are that duplication dates bound functions from above, that the priors shape which family can be older, and that the authors themselves cannot order phagocytosis and the mitochondrion. | Active |
| THEORY-1100 v2 | On Sørensen and colleagues’ review, a bacterial endosymbiont becomes genetically integrated, the authors’ mark of an organelle, when nuclear genes whose products are imported into it functionally replace essential genes it has lost, and this does not require gene transfer from the endosymbiont: in the Paulinella chromatophore and the nitroplast, the two systems with hundreds of imported proteins, many of which fill gaps left by lost genes, the imported proteins come mostly from the host’s own genes or from other bacteria, and in the nitroplast no gene transfer from the endosymbiont has been found | Sørensen, Stiller, Kröninger & Nowack (2025), LIT-1560, read in NOTE-1241. Protein mass spectrometry of isolated endosymbionts found hundreds of host proteins imported into Paulinella’s chromatophore and more than 350 into the nitroplast, where they fill gaps left by lost genes. In Paulinella the imported proteins come mostly from the host’s own genes, with some from gene transfer from the chromatophore and from other bacteria. In the nitroplast no gene transfer from the symbiont has been found at all. So the route to an organelle is import, and the endosymbiont’s genes need not move. The origins are stated in summary, not counted, and the import mechanisms are unknown. | Active |
| THEORY-1101 v3 | Tobiasson, Luo, Wolf and Koonin find, on 5,850 eukaryotic gene stems, that normalized stem length does not behave as a clock of acquisition time: alphaproteobacterial stems are longer than Asgard ones for the 70% of stems below 0.3 and shorter only above 0.35, oxidative-phosphorylation genes presumed acquired together vary by more than two orders of magnitude, and information-processing genes have short stems; they conclude that even normalized stem lengths are set primarily by factors other than acquisition time, at least over the long timescales analysed, and suggest that adaptation after acquisition lengthens stems | Tobiasson, Luo, Wolf & Koonin (2026), LIT-1558, read in NOTE-1242. They test the stem-length method of Pittis and Gabaldón on their own trees and reproduce its mitochondrion-late signal only for long stems. Below 0.3, where 70% of stems lie, the order reverses, and genes presumably acquired together scatter widely. They conclude that “even normalized stem lengths are determined primarily by factors other than the gene acquisition time”. The paper still favours a late mitochondrion, on other grounds. | Active |
| THEORY-1102 v2 | On Pittis and Gabaldón’s stem-length analysis of the LECA proteome, families of alphaproteobacterial origin and mitochondrial location sit closer to their prokaryotic relatives, after correction for each family’s rate, than families of other bacterial origin (P = 0.044), which sit closer than archaeal families, and the authors read this as late acquisition of the mitochondrion by a host whose proteome was already chimaeric, under their stated assumption that rates before and after LECA are correlated | Pittis & Gabaldón (2016), LIT-1595, read in NOTE-1240. Of 1,078 LECA families, bacterial ones have shorter normalized stems than archaeal ones (P = 1.38e-25), and alphaproteobacterial ones shorter than other bacterial ones (P = 0.044). Origin tracks location: alphaproteobacterial with the mitochondrion, other bacterial with endomembranes, archaeal with the nucleus. A plastid control runs the right way. The sharp edges are that stem length measures distance to the closest sampled relative, so sampling can move it, and that the chimaeric host could have come from partners or from transfer, which the paper cannot tell apart. | Active |
| THEORY-1103 v2 | On Shigenobu and colleagues’ genome of Buchnera sp. APS, the aphid symbiont keeps the genes for the amino acids its host cannot make and has lost almost all of those its host can, uses host-made glutamate and aspartate as precursors, and lacks phospholipid synthesis and nearly all its own transcriptional regulators, so that its metabolism interlocks with the host’s and it presumably lives only inside the bacteriocyte, a state reached by gene loss from an E. coli-like ancestor | Shigenobu et al. (2000), LIT-1596, read in NOTE-1236. The first complete genome of an obligate insect endosymbiont: 640,681 bp, a subset of E. coli’s. What is shown is gene content. The interlocking of host and symbiont metabolism is inferred from it and from earlier physiology. That Buchnera cannot live outside the bacteriocyte, and that the host supplies its membrane lipids, are the authors’ inferences. The paper names no mechanism of loss beyond a homeostatic niche: it says nothing of drift. | Active |
| THEORY-1104 v3 | In Tobiasson, Luo, Wolf and Koonin’s constrained-tree survey of widespread eukaryotic protein families, Asgard archaea are the largest single prokaryotic source, with about half the likelihood weight in the best-resolved families and the lead in nearly every functional system, while Alphaproteobacteria contribute a small, coherent set centred on the mitochondrion and other bacteria about a third of families, scattered across functions with no pathway led by one donor except a narrow Myxococcota signal in nucleotide-sugar and nicotinate metabolism; the authors read this as one Asgard host lineage, one endosymbiont and piecemeal gene transfer rather than further symbioses | Tobiasson, Luo, Wolf & Koonin (2026), LIT-1558, read in NOTE-1242. In 4,290 well-resolved eukaryotic–prokaryotic clusters, Asgard takes 50% of likelihood weight and leads in almost every functional class. Alphaproteobacteria account for mitochondrial translation, oxidative phosphorylation and 4Fe-4S assembly. About a third of clusters point elsewhere, with no functional pattern except a narrow Myxococcota signal. The authors infer a complex Asgard ancestor, a late mitochondrion and “no indication of another symbiotic event”. The composition is shown; the scenario is read off it. | Active |
| THEORY-1105 v3 | In Bernabeu, Manzano-Morales, Marcet-Houben and Gabaldón’s reconstruction of the last eukaryotic common ancestor’s proteome, two bacterial phyla besides the mitochondrial ancestor, Myxococcota and Planctomycetota, each account for a share of the proteome comparable to that of Alphaproteobacteria and Asgard archaea under thresholds calibrated on those accepted partners, and stem-length distributions order the acquisitions as waves, Asgard first, then Planctomycetota, then the mitochondrial ancestor and Myxococcota together; the authors read this as serial associations with several partners, while conceding that their data cannot say whether any donor was a symbiont | Bernabeu, Manzano-Morales, Marcet-Houben & Gabaldón (2026), LIT-1561, read in NOTE-1237. Under thresholds chosen to maximize assignments to Alphaproteobacteria and Asgard, Myxococcota (3.92% of the proteome) and Planctomycetota (2.24%) pass in every dataset, beside Alphaproteobacteria (3.99%) and Asgard (3.28%). A control removing Alphaproteobacteria from the database does not reproduce their pattern. Stem lengths put Planctomycetota before the mitochondrion. The authors “challenge models depicting eukaryogenesis as a one-off event resulting from a binary symbiotic interaction”, and also say their data “do not provide information on the host or endosymbiotic nature of any partner”. | Active |
| THEORY-1106 v2 | Campbell and colleagues report, from four cicada species with five or six eggs each, that Hodgkinia cells per egg range from about 4,900 in a species with one Hodgkinia lineage to about 30,000, some six times as many, in Magicicada septendecim, whose Hodgkinia has split into many interdependent lineages and the only species that differs significantly, while Sulcia numbers are not raised, the transmission route is the same, and every egg sampled carries every lineage tracked by marker genes; the authors take the raised titre as a host adaptation that compensates for the symbiont’s fragmentation, and a cost of it | Campbell, Łukasik, Meyer, Buckner, Simon, Veloso, Michalik & McCutcheon (2018), LIT-1590, read in NOTE-1235. Measured: Hodgkinia cells per egg from 4,889 in a single-lineage cicada to 30,154 in M. septendecim, with Sulcia at 2,572 to 5,643; marker genotypes present in every egg sampled; the same route under the light microscope. Not shown: a trend across complexity beyond M. septendecim, or that splitting came first. The authors also speculate that a larger transmitted population weakens bottlenecks and could feed further splitting. | Active |
| THEORY-1107 v2 | On Sørensen and colleagues’ scenario, an endosymbiont becomes an organelle in steps: the host first targets effector proteins into it; an imported host protein redundant with one of its functions then lets the endosymbiont’s own gene decay, making it dependent; and a general import pathway, once evolved, brings in hundreds of proteins; this genetic integration arises only in permanent, vertically transmitted associations, and host effector control without vertical transmission, as in rhizobia, does not lead to it | Sørensen, Stiller, Kröninger & Nowack (2025), LIT-1560, read in NOTE-1241. Their closing scenario orders the steps from endosymbiont to organelle: effectors first, then dependence through one redundant imported protein, then many imported proteins once a targeting signal evolves. Rhizobia, targeted by about 700 host peptides yet not vertically transmitted, are their case of control without integration. It is a scenario built from systems at different stages, not a sequence observed in any one. | Active |
| THEORY-1108 v2 | On Imachi and colleagues’ cultivation of Candidatus Prometheoarchaeum syntrophicum MK-D1, the first Asgard archaeon grown in the laboratory is a small, internally simple coccus with long branching protrusions that degrades amino acids only in syntrophy, handing hydrogen and formate to partners that can be exchanged, and from its genome and other Asgard genomes the authors infer that the Asgard ancestor was likewise dependent on metabolic partners; the isolate is a modern relative separated from the host lineage by about two billion years, grown only in co-culture, and the entangle–engulf–endogenize model built on it is a hypothesis the authors call not definitive | Imachi et al. (2020), LIT-1591, read in NOTE-1238. Partner inhibitors impair MK-D1’s growth, added hydrogen or formate stops it, and it grows with either of two methanogens, so its dependence is on a service that several partners can supply. Cryo-EM and TEM show no internal compartments. The step from this one organism to the Asgard ancestor is a genomic inference, which the authors hedge. The sharp edge for the record is that the most famous transition in individuality may have begun from a host already dependent on others, with no partner specificity, cohesion or control. | Active |
| THEORY-1109 v3 | Santana-Molina, Williams, Snel and Spang find that the last eukaryotic common ancestor’s central carbon metabolism was chimeric: a few Asgard-archaeal enzymes in cytosolic glycolysis and the pentose phosphate pathway, four placed with Asgard archaea at bootstrap 39–97% and two ambiguously, most alphaproteobacterial ones in the mitochondrial TCA cycle and pyruvate conversion, and others from various bacteria with no third dominant donor, since remodelled by loss, horizontal replacement and retargeting so that compartment no longer follows origin; the authors take the cytosol–mitochondrion split as support for syntrophy | Santana-Molina, Williams, Snel & Spang (2025), LIT-1564, read in NOTE-1239. LECA had a complete central carbon metabolism. Six enzymes are placed with Asgard archaea, mostly cytosolic (bootstrap 39–97%, two ambiguous). Seventeen are alphaproteobacterial, ten of them in the TCA cycle, mostly mitochondrial. Others come from several bacteria, none dominant. Since LECA, Asgard enzymes have been replaced in many lineages and enzymes retargeted regardless of origin. The authors read the split as support for syntrophy; it does not discriminate syntrophy from other symbiogenetic models. | Active |
| THEORY-1197 | Eukaryogenesis involved one archaeal host lineage, of Asgard descent, and one bacterial endosymbiont, the alphaproteobacterial ancestor of mitochondria; the eukaryotic genes from other bacteria came by piecemeal gene transfer, not from further symbiotic partners | The wider thesis Tobiasson, Luo, Wolf & Koonin assert, filed beside THEORY-1104 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1104, Active, holds what Tobiasson and colleagues’ survey finds and how the authors read it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1104’s old condition, word for word. | Proposed |
| THEORY-1200 | The Asgard archaeal ancestor of eukaryotes depended on metabolic partners: like Candidatus Prometheoarchaeum syntrophicum, it degraded amino acids in syntrophy, handing hydrogen and formate to partners that removed them | The wider thesis Imachi et al. assert, filed beside THEORY-1108 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1108, Active, holds what Imachi and colleagues’ cultivation shows and what they infer from it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1108’s old condition, word for word. | Proposed |
| THEORY-1201 | Normalized stem length is not a clock of gene acquisition time: it is set mainly by factors other than when a gene was acquired, such as adaptation to the new cell after acquisition, so relative timings of eukaryogenesis drawn from stem lengths alone are not supported | The wider thesis Tobiasson, Luo, Wolf & Koonin assert, filed beside THEORY-1101 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1101, Active, holds what Tobiasson and colleagues find and conclude; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1101’s old condition, word for word. | Proposed |
| THEORY-1203 | The host lineage elaborated its cytoskeleton, endomembrane system and nuclear machinery before mitochondrial endosymbiosis began, about 2.2 billion years ago: most pre-LECA duplications in eukaryotic gene families of archaeal origin predate it | The wider thesis Kay et al. assert, filed beside THEORY-1099 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1099, Active, holds what Kay and colleagues’ dating finds and how the authors read it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1099’s old condition, word for word. | Proposed |
| THEORY-1205 | Eukaryotes began in a syntrophic partnership: an archaeal host fermented sugars and passed reducing equivalents to an alphaproteobacterial endosymbiont that contributed a TCA cycle and an electron transport chain, which is why the last eukaryotic common ancestor’s central carbon metabolism is archaeal in cytosolic glycolysis and the pentose phosphate pathway and alphaproteobacterial in the mitochondrial TCA cycle | The wider thesis Santana-Molina, Williams, Snel & Spang assert, filed beside THEORY-1109 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1109, Active, holds what Santana-Molina and colleagues find and how they read it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1109’s old condition, word for word. | Proposed |
| THEORY-1206 | The mitochondrion was acquired late in eukaryogenesis, by a host whose proteome was already chimaeric, with genes from several bacterial sources acquired before it | The wider thesis Pittis & Gabaldón assert, filed beside THEORY-1102 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1102, Active, holds what Pittis and Gabaldón’s analysis finds and how the authors read it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1102’s old condition, word for word. | Proposed |
| THEORY-1208 | Bacterial endosymbionts lose their cell-envelope and envelope-transport genes together below about 400 kb and begin to lose translation genes below about 200 kb, and the host supplies the membranes, transport and protein synthesis that the smallest-genome symbionts no longer encode, as for organelles | The wider thesis McCutcheon, Garber, Spencer & Warren assert, filed beside THEORY-1049 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1049, Active, holds what McCutcheon and colleagues’ survey shows and what they infer from it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1049’s old condition, word for word. | Proposed |
| THEORY-1211 | An endosymbiont becomes an organelle in steps: the host first targets effector proteins into it; an imported host protein redundant with one of its functions then lets the endosymbiont’s own gene decay, making it dependent; and a general import pathway, once evolved, brings in hundreds of proteins; this genetic integration arises only in permanent, vertically transmitted associations | The wider thesis Sørensen, Stiller, Kröninger & Nowack assert, filed beside THEORY-1107 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1107, Active, holds the scenario Sørensen and colleagues propose; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1107’s old condition, word for word. | Proposed |
| THEORY-1214 | Cicada hosts whose endosymbiont Hodgkinia has split into many interdependent lineages compensate by sending more Hodgkinia cells to each egg, with Sulcia numbers and the transmission route unchanged, so that every egg still receives every lineage; the raised titre is a host adaptation driven by the symbiont’s fragmentation, and a cost of it | The wider thesis Campbell et al. assert, filed beside THEORY-1106 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1106, Active, holds what Campbell and colleagues measured and how they read it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1106’s old condition, word for word. | Proposed |
| THEORY-1215 | Besides Asgard archaea and the alphaproteobacterial ancestor of mitochondria, Myxococcota and Planctomycetota were major donors of genes to the eukaryotic lineage before its last common ancestor, in waves: Asgard first, then Planctomycetota before the mitochondrion, then the mitochondrial ancestor and Myxococcota together | The wider thesis Bernabeu, Manzano-Morales, Marcet-Houben & Gabaldón assert, filed beside THEORY-1105 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1105, Active, holds what Bernabeu and colleagues’ reconstruction finds and how the authors read it; whether that is true is this entry’s question, and its promote_when is THEORY-1105’s old condition, word for word. | Proposed |
| THEORY-1219 | Buchnera’s metabolism interlocks with its aphid host’s: it makes the essential amino acids its host cannot from host-supplied glutamate and aspartate, depends on the host for the non-essential amino acids and its membrane phospholipids, and cannot live outside the bacteriocyte | The wider thesis Shigenobu, Watanabe, Hattori, Sakaki & Ishikawa assert, filed beside THEORY-1103 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1103, Active, holds what Shigenobu and colleagues’ genome shows and what they infer from it; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1103’s old condition, word for word. | Proposed |
| THEORY-1223 | Monocercomonoides exilis lost its mitochondrion only after the organelle’s essential functions had been removed in steps, Fe–S cluster assembly to a cytosolic SUF system and then the glycine cleavage system by loss, and the loss required no compensating change elsewhere in the cell | The wider thesis Karnkowska et al. assert, filed beside THEORY-1098 by the twenty-second status review (ADR-065 §3; ADR-047 kind 1). THEORY-1098, Active, holds what Karnkowska and colleagues’ genome analysis finds and infers; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1098’s old condition, word for word. | Proposed |
| THEORY-1228 | A bacterial endosymbiont becomes genetically integrated, an organelle, when host proteins imported into it replace genes it has lost, and this does not require gene transfer from the endosymbiont: in the Paulinella chromatophore and the nitroplast, the two systems with hundreds of imported proteins, the replacing genes are mostly the host’s own or come from other bacteria | The wider thesis Sørensen, Stiller, Kröninger & Nowack assert (“EGT is not a precondition for the genetic integration of an endosymbiont”), filed beside THEORY-1100 by the twenty-third status review (ADR-065 §3; ADR-047 kind 1). THEORY-1100, Active, holds what the review reports; whether the thesis holds is this entry’s question, and its promote_when is THEORY-1100’s old condition, word for word. | Proposed |
| THEORY-1235 | Losing a costly function whose product leaks to neighbours is favoured by ordinary individual selection in large free-living microbial populations, and the loss proceeds until the remaining producers just supply the community, so that most cells come to depend on a rare few with no relatedness, cooperation or collective required | The Black Queen Hypothesis itself, filed beside THEORY-1048 by the twenty-fourth status review (ADR-065 §3; ADR-047 kind 1). THEORY-1048, Active, holds what the hypothesis says; whether it is true is this entry’s question, with THEORY-1048’s old condition word for word. | Proposed |
| THEORY-1243 | In incipient endosymbioses in nature, mutual dependence evolves ahead of reproductive cohesion, so that endosymbioses are more likely to be mutually dependent than cohesive | The inference Athreya, Czuppon and Gokhale draw for nature, filed beside THEORY-1050 by the twenty-fourth status review (ADR-065 §3; ADR-047 kind 1). THEORY-1050, Active, holds the model result and its dependence on the trait mapping; whether real symbioses are dependence-first is this entry’s question, with THEORY-1050’s old condition. | Proposed |