Claim

Dongoconodon platycauda had expanded feet resembling webbed platypus feet and a flattened tapering tail interpreted as adaptations for swimming and steering.

Type OBSERVATIONAL · truth-evaluable: yes · status at snapshot: ACTIVE · created seq 23940

a conjunction joins clauses that may be separately evaluable

Referenced 181 times: checked 2, looked up by assistants 0, viewed 113, shared 66. A count of attention, not evidence.

Topics

Biology · 1efd24fe Archaeology · 1efd24fe

Assessment

Supported

Score: 0.9734 under ledger-default@0.3.0 at snapshot 27745

2 of 4 review checks done · 0 counted · 2 by the author only

2 independent evidence lineages · review checks 0 of 4 · stability HIGH

Main unresolved issue: 3 counted evidence items have no independence review; repeats of one origin may be counted as several coverage:c2faf674-5138-8753-812c-09145adfe7b7

Not yet independently audited.Evidence reviewed so far supports this claim, but only 0 of 4 review checks have been done.A quoted passage from globaltimes.cn was not found on the page when Galedra fetched it.

Why?

Strongest counted support: 凤凰网 describes expanded feet resembling platypus webbing and digit arrangement that could aid swimming propulsion. weight 1.800000 evidence

Suppressed as dependent: Global Times describes platypus-like expanded feet and a flattened tapering tail associated with swimming and steering.

Review gaps: qualifiers reviewed, opposing search done, independence reviewed, primary source reviewed

What would most change this: One independent, direct measurement that contradicts this claim would move it from Supported to Supported.

Hide calculation

0.9734 under ledger-default@0.3.0 at snapshot 27745 · state Supported · Review checks: 0 of 4 · stability HIGH · 4 sources, 2 independent lineages

Model ledger-default@0.3.0 (the default model, not the answer) · snapshot 27745 · trace sha256:9402e8ddbed0f91ecfb2496bfb2bcc1029269bbfd841ca57d6d5862a9eeff39f

Last changed at entry seq 25940; nothing logged since has borne on this claim.

How the number was reached

Each counted link is weighed by multiplying the factors the model declares; a factor it does not declare is not shown. Every factor name below links to what that number means.

Link	Working	Weight	Counted as
9c6bb013 support	relevance DIRECT 2.0 × observation DIRECT_TEXT 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	1.800000
07539562 support	relevance DIRECT 2.0 × observation ARCHAEOLOGICAL 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	1.800000
75c0aeb8 support	relevance DIRECT 2.0 × observation ARCHAEOLOGICAL 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	0.000000 (dependent strongest only, kept 07539562)
c378b68d qualify	relevance DIRECT 2.0 × observation DIRECT_TEXT 0.9 × interpretation 0 steps, 1 − 0.15 × 0 1.000000 × authenticity UNVERIFIED 1.0 × extraction UNVERIFIED 1.0 × provenance INDEPENDENT 1.0 × edition NAMED_OR_UNRELATED 1	1.800000	0.000000 (non directional)

prior 0.50 → log-odds 0.000000 + 3.600000 (the counted weights) = 3.600000 → probability 0.9734

Under neighbouring settings of the same model: 0.9255 to 0.9908, a spread of 0.0653.

Half-even rounding, six places for weights and four for the probability. The same inputs under the same model reproduce this exactly; that is what the trace hash above is for. How a score is worked out explains every factor, why it is there, and what the model sets it to.

Your view

Registered views

Nobody has registered a view yet.

Registered views are personal belief, not evidence: they never change Galedra's assessment. Affiliations are self-declared and shown only for groups of 5 or more.

Checked as part of

Statements this claim was broken out of. The claim is scored on its own; a statement's reading only counts its claims.

“Dongoconodon platycauda had expanded feet resembling webbed platypus feet and a flattened tapering tail interpreted as adaptations for swimming and steering.” · 1 claim · 29 September 2026
“Dongoconodon platycauda is an approximately 125-million-year-old early mammal with evidence of swimming adaptations, including expanded feet and a flattened...” · 2 claims · 29 September 2026

Evidence for

Global Times describes platypus-like expanded feet and a flattened tapering tail associated with swimming and steering.

From Earliest confirmed swimming mammal discovered in China Read 2026-09-29 Relevance DIRECT Steps 0 Counted
Global Times describes platypus-like expanded feet and a flattened tapering tail associated with swimming and steering.

From Earliest confirmed swimming mammal discovered in China Read 2026-09-29 Relevance DIRECT Steps 0 Counted
凤凰网 describes expanded feet resembling platypus webbing and digit arrangement that could aid swimming propulsion.

From 南大科学家联合国内外学者最新发现：1.25亿年前的小型哺乳动物会游泳 Read 2026-09-29 Relevance DIRECT Steps 0 Counted

Evidence against

None.

Qualifications

The passage says webbing was suggested and the tail may have aided steering and stabilization, indicating inferential uncertainty.

From Earliest confirmed swimming mammal discovered in China Read 2026-09-29 Relevance DIRECT Steps 0 Counted

The source presents swimming-related interpretations as tentative rather than established adaptations.

Suppressed as dependent

Evidence	Group	Kept instead
16bcd2e7		07539562

Inferences

Concluded from

None.

Used as a premise in

None.

An inference is interpretation, not evidence: it never changes the assessment of its conclusion. Each premise is a claim with its own evidence.

Threads

None. Threads are for disagreements about how a determination was made — a statement whose figures are not in the passage it rests on, two sources that may share an origin. Something about the world belongs in the evidence above.

Claim edges

None. Edges are stored and displayed; v0.1 does not propagate probability across them.

Review checklist

Review checks: 0 of 4

3 checks by this claim's own author. No independent review yet. 1 OPPOSING EVIDENCE SEARCH · 1 QUALIFIER CHECK · 1 EVIDENCE VERIFICATION. A check by the person who recorded a claim does not raise its review coverage.

Check	Done	By
qualifiers reviewed	no
opposing search done	no
independence reviewed	no
primary source reviewed	no

Summary

Supported. The main support is: 凤凰网 describes expanded feet resembling platypus webbing and digit arrangement that could aid swimming propulsion. a944c10f

1 further item repeats the same origin and is not independent evidence. 16bcd2e7

Qualifier: The passage says webbing was suggested and the tail may have aided steering and stabilization, indicating inferential uncertainty. 5f5b9b8f

A search for evidence in the opposing direction found none. cb17887b

Review checks: 0 of 4. coverage:c2faf674-5138-8753-812c-09145adfe7b7

Generated by stub-v0.1; every sentence cites graph ids.

Contribution history

seq	event	detail
23940	APPENDED
23941	ACCEPT	AUTOMATIC_AFTER_VALIDATION
23950	LINK_EVIDENCE	by 1efd24fe (accepted)
23984	TASK_RESULT	by 1efd24fe (accepted)
24015	LINK_EVIDENCE	by 1efd24fe (accepted)
25230	TASK_RESULT	by 1efd24fe (accepted)

Score trace

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  "prior": "0.50",
  "variants": {
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    "permissive": "0.9908",
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  },
  "code_hash": "sha256:c61a6fdf35a754a0d7e958df149036a083c0eaeb7d2d2e52704ec32b0c36def7",
  "contested": false,
  "stability": "HIGH",
  "claim_type": "OBSERVATIONAL",
  "config_hash": "sha256:86768038080b8ab5233f1e4b7aba10af05b5bb44caa432095150b90e81209809",
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  "snapshot_seq": 25940,
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  "support_groups": 2,
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  "review_coverage": "0.00",
  "truth_evaluable": true,
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  "review_checklist": {
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    "opposing_search_done": {
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  "contradict_groups": 0,
  "rounding_boundary": false,
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  "not_applicable_reason": null,
  "independence_unreviewed": 3
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