Bluefish Caves

What happened

1. 1977Jacques Cinq-Mars begins excavations for the Archaeological Survey of Canada; work continues to 1987.
2. 1979Cinq-Mars reports stone tools and Ice Age bones in Cave I and dates human use to 13,000–10,000 radiocarbon years ago.
3. 1982Morlan and Cinq-Mars publish the earliest suggestion that Bluefish bone dates could indicate use before the Last Glacial Maximum.
4. 2003Morlan notes that regional summaries start the record at 11,500–12,000 14C BP and dismiss or ignore older evidence.
5. 2008Harington and Cinq-Mars summarize the case: flaked mammoth bone (~23,500 14C BP) and a split caribou tibia (24,800 14C BP).
6. 2015Bourgeon's taphonomic study of Cave II finds most bone damage non-human, with a small part possibly human-made.
7. 2017Bourgeon, Burke and Higham report 15 cut-marked bones; the oldest, a horse jaw, dates to 19,650 ± 130 14C BP (~23,500 cal BP, IntCal20).
8. 2018Potter et al. call the Bluefish record 'enigmatic,' reading it as possible evidence of population pulses into eastern Beringia as early as 24,000 years ago.
9. 2019A Kansas-led team tests Cave III (no stone tools found) and locates an unexcavated Cave IV.
10. 2020Krasinski and Blong argue that disturbed contexts and natural bone damage leave the site 'provocative but unconvincing'.
11. 2023Litynski and Pante's experiments suggest rockfall is an improbable cause of the marks on the dated bone.
12. 2026Cave III studies find no human traces there; site researchers say the Caves I–II evidence still 'spurs controversy'.

Objections 0 of 4 proved wrong

• ?
  Archaeological contexts were significantly disturbed, so the stone tools and the LGM-age dated bones may not be reliably associated with each other or their reported depths.

  Layers or association · Dixon et al. (1999–2008); developed by Krasinski & Blong (2020) · 1999

  Unresolved — Direct dates on cut bones avoid association problems for those bones, but S1 says depth 'could not be established' for most dated specimens, and a 2026 study found no depth–age relationship in Cave III (S9, S15).
• ?
  Breaks and grooves on the bones could come from rockfall or carnivore chewing rather than human butchery and toolmaking.

  Natural, not human · Dixon (1999); Hoffecker & Elias (2007); Goebel et al. (2008) · 1999

  Unresolved — A 2023 experiment found rockfall 'an improbable cause' for marks on the dated bone (title only, S13); natural damage from carnivores or trampling is still argued for the wider assemblage (S9).
• ?
  No other eastern Beringian sites of similar age were known, making the pre-LGM signal hard to corroborate independently.

  Contradicts the accepted model · Dixon (1999); Hoffecker & Elias (2007); Goebel et al. (2008) · 1999

  Unresolved — S1 calls the claim 'controversial in the absence of other sites of similar age.' Potter et al. (2018, S10) instead read it as possible evidence of early population pulses; no second site is confirmed.
• ?
  The oldest ages rest on 1980s bone dates whose specimens' artifact status is uncertain; a comparable regional bone date was later shown wrong by tens of thousands of years.

  Dating or samples · Regional dating precedent (Nelson et al. 1986) · 1986

  Unresolved — Nelson et al. (1986) redated four Yukon bone 'artifacts' to the late Holocene; one (Old Crow flesher) was off by almost 26,000 years. The Bluefish tibia and mammoth bone remain undated since the 1980s.

Evidence at the time within ~5 years of the claim

• Unambiguous evidencePartly — Stone tools are clearly human-made; the pre-LGM bones (tibia, mammoth core/flake) are broken and marked bone, whose human origin S1 calls controversial from the start.
• Documented contextPartly — Excavated in stratified loess and described as primary or near-primary context (1978 season); later study found the cave fills also include carnivore-accumulated bone (see objections).
• Independent dating methodsNo — Radiocarbon dates on bone are the only dating method behind the pre-LGM ages; pollen and fauna are consistent with them but are not independent dating methods.
• More than one labUnknown — The 24,800 and ~23,500 14C BP dates appear only as figures (S4; per S5, personal communication), no lab named. A younger bone (RIDDL-278) shows multi-lab dates existed by the 1980s.
• Professional recoveryYes — Excavated 1977–1987 under Jacques Cinq-Mars, Archaeological Survey of Canada.
• Peer-reviewed reportUnknown — The earliest print of the pre-LGM suggestion (Morlan & Cinq-Mars 1982) is an edited-volume chapter; whether it had journal-style peer review is unconfirmed, and it is paywalled and unread.
• Open to criticsUnknown — Collections are kept at the Canadian Museum of History; access for critics in the 1980s is not documented in sources read.
• Independent teamsNo — Through the 1980s, reports came from Cinq-Mars and co-authors (Morlan; Ritchie and Cwynar on pollen).
• Outside stakeNo — No motive beyond ordinary career interest is documented; Cinq-Mars was a federal museum archaeologist.

What would settle it for a field partner

1. Blind re-study of the 15 cut-marked and 20 'probable' bones at the Canadian Museum of History by an independent taphonomy lab, using 3-D micro-morphometrics.Medium cost
   Would show: Whether the marks are stone-tool cuts rather than carnivore, trampling or rockfall damage.
2. Re-date the cut-marked horse jaw (OxA-33778) and caribou pelvis (OxA-33777) at a second laboratory, ideally by single-amino-acid (hydroxyproline) AMS dating.Low cost
   Would show: Whether the ~24,000–22,000 cal BP ages are free of contamination.
3. AMS-date the mammoth bone core, its refitting flake and the split caribou tibia with modern pretreatment, and publish full lab data.Low cost
   Would show: Whether the oldest claimed tools really date to ~23,500–24,800 14C BP.
4. Complete excavation of Cave IV to bedrock (2022 units reached ~1 m short) with piece-plotting, micromorphology and direct dates on cut bone or stone tools, done by the permitted team with community partners.High cost
   Would show: Whether undisturbed LGM-age cultural layers exist at the site.

What would change this record

An independent re-study showing the dated marks are carnivore, trampling or rockfall damage, or re-dates placing the cut bones after the LGM, would refute LGM use. Intact cultural layers dated to ~23,500 cal BP in Cave IV or nearby would confirm it.

Notes

• Status. Cut-marked bones date to ~23,500 cal BP (IntCal20), supporting LGM visits; a 2023 test finds rockfall unlikely (S13). Critics (S9, S11) cite disturbed deposits, call early sites 'equivocal'; 2026 work still 'spurs controversy' (S15).
• Accepted view then. Eastern Beringian summaries began the record at the Nenana complex, ~11,500–12,000 14C BP (~13,400–13,900 cal BP), the limit for accepted sites.
• Dating basis. Oldest proponent dates (Morlan & Cinq-Mars 1982): 24,800 14C BP on a caribou tibia (possibly a fleshing tool, S4); ~23,500 on a mammoth bone core/flake. Calendar figure approximates IntCal20 (S20).
• Correction. The brief says Cinq-Mars argued for ~25,000 years 'from the late 1970s.' The 1979 paper claimed only 13,000–10,000 BP; the pre-LGM figure is credited by S1 to Morlan & Cinq-Mars (1982) and later works, not the 1970s.
• Correction. Excavations ran from 1977 to 1987, not only in the late 1970s.
• Correction. The oldest 2017 directly-dated cut-marked bone is a horse jaw at 19,650 ± 130 14C BP (~23,500 cal BP, IntCal20; ~24,000 under IntCal13). It is younger than the undated 1980s tibia/mammoth claims (23,500–24,800 14C BP).
• Correction. Status is open, not vindicated: critics call the evidence 'provocative but unconvincing' (2020) and judge all comparably old sites 'equivocal' (2022); a 2023 paper co-authored by Bourgeon says interpretation 'has been disputed'.
• Correction. The 2017 re-study found wolves, lions and foxes were the main bone collectors; under 1% of the 36,000 bones studied show human or probable human marks.
• year_claimed (1982) anchors the record on the pre-LGM claim, credited by S1 to refs 24–27 (Morlan & Cinq-Mars 1982; Cinq-Mars 1990; Cinq-Mars & Morlan 1999; Harington & Cinq-Mars 2008); the earliest is S3, paywalled and unread beyond Crossref metadata, so peer_reviewed_report and some other features are marked unknown. The 1979 claim (13,000–10,000 BP, S2) stays in the timeline as the first public claim. orthodoxy_at_claim cites S6 (2003), the best available description of the persistent Nenana/Clovis-first framework; no 1982-specific orthodoxy source was found. RIDDL-278 (S1) dated a different, younger bone (17,440 14C BP), not the 23,500–24,800 BP specimens in claimed_age.

People and evidence

• Proponents. Jacques Cinq-Mars, Richard E. Morlan, C. Richard Harington, Lauriane Bourgeon, Ariane Burke, Thomas Higham
• Critics. Kathryn E. Krasinski, John C. Blong, Ben A. Potter, E. James Dixon
• Evidence types. radiocarbon, stratigraphy, lithics, artifacts, fauna · 2 independent lines
• Record confidence. medium — The pre-LGM claim's 1982 first-print is inferred from S1's reference list; S3, Cinq-Mars 1990 and Cinq-Mars & Morlan 1999 are unread. Calendar-year figures are approximate, not OxCal-run.