Our cellular host ancestor arose within Asgard archaea.

This is the frozen contract wording. Read the YES and NO tests, the evidence requirements and the undecided cases before taking a position.

Canonical title

The eukaryotic host lineage arose within Asgard archaea.

Exact hypothesis · technical wording

The archaeal host lineage ancestral to all extant eukaryotes branches strictly inside crown Asgard, defined by the last common ancestor of Loki-, Thor-, Odin- and Heimdallarchaeota and its descendants. The complement includes EVERY placement outside that crown: sister to all Asgard, any deeper or other branch within Archaea, sister to all Archaea, and other nonnested placements. Host ancestry is tested using vertically inherited informational genes, not mitochondrial ancestry or transferred genes.

Each round reads the evidence that was public at a stated cutoff. Later evidence goes into a later round; the market itself has no expiry date.

Resolution criteria

YES: Independent phylogenomic datasets with >= 30 vetted single-copy informational orthologues support crown nesting with >= 95% nonparametric bootstrap support. For each dataset, freeze a reference taxon set containing the four defining Asgard groups, non-Asgard archaeal diversity and justified outgroups before topology testing. Under the same site-heterogeneous model, optimize branch lengths and nuisance parameters for constrained maximum-likelihood placements of the host lineage on EVERY edge of that reference backbone, inside and outside crown Asgard; repeat over supported alternative backbones/rootings. An approximately unbiased test with >= 10000 multiscale bootstrap replicates must reject every nonnested candidate at p < 0.01 while retaining at least one nested candidate. Paralogy/transfer screening and taxon-removal analyses must retain the conclusion. An incomplete placement search cannot settle YES. NO: The identical search and eligibility requirements instead give >= 95% bootstrap support to a nonnested placement and reject EVERY nested candidate at p < 0.01 while retaining at least one nonnested candidate. A deeper archaeal placement is eligible NO, not an omitted alternative. Unresolved rooting/backbones, inadequate evolutionary models, dependence on transferred genes or sensitivity to taxon removal leave the market UNDECIDED; these thresholds do not eliminate phylogenetic judgment. Reference sources: Liu et al.: expanded Asgard diversity (https://www.nature.com/articles/s41586-021-03494-3); Zhang et al.: deep eukaryotic origin within Asgard (https://www.nature.com/articles/s41586-025-08955-7); Asgard archaea and eukaryotic complexity (https://www.nature.com/articles/nature21031). Evidence policy: use public primary research with methods and uncertainty, plus the named reference sources below. A preprint can inform the estimate but cannot alone meet a terminal criterion; require a peer-reviewed primary result and an independent reproduction using non-overlapping observations or independently prepared samples, unless this is a mathematical proof or the specific criterion instead requires independently implemented calculations. Report data provenance, exclusions, calibration, statistical model and systematic uncertainty. Independence means different data acquisition, not two papers reanalysing the same sample. For a quantitative terminal test, both independent results must meet the stated threshold; disagreement or an interval crossing the boundary means UNDECIDED. Use the final corrected version public at the signed round's evidence cutoff (UTC); exclude later evidence until a later eligible round. Every report in a terminal round must use the same cutoff, covered by the verified signed context and enforced by the configured terminal protocol; a different cutoff requires a new eligible round, never reinterpretation of a signed report or mutation of an immutable binding. This market has no calendar expiry. Retracted findings cannot supply a terminal result. If a named source disappears, use its DOI/publisher or an archived identical version, then an equivalent primary publication applying these unchanged definitions; if none is accessible, remain UNDECIDED, never substitute a different test. Missing data, failed replication, a null search outside the specified domain, or an untested alternative is not automatically NO. These are instructions for evidence assessment, not an automatic truth oracle: scientific interpretation and systematic-error judgment remain. Settlement follows the configured platform mode: terminal mode requires one valid round with all three frozen models returning the same explicit YES or NO and criterion_met=true; any UNDECIDED, failure or disagreement leaves it unresolved. Legacy proposal/challenge mode requires its recorded review process. Model agreement does not prove scientific truth. Invalidity is not NO and this text does not authorize a refund or cancellation: only a cancellation rule disclosed before exposure, if the configured contract supports it, can apply. Otherwise pause new entries and preserve holders' existing rights. Never reinterpret terms after listing.

The definition does not change when an AI estimate changes. Read the listing policy and this market's settlement status.